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Coming back from a MustangUnlimited car show, cruising about 2,800 rpm on the highway and then a flapping noise from the engine area. In the left lane of 3 lane highway, dipped clutch, engine stalled, pulled over to the right. No obvious external damage or leaks etc. Flat-bedded home and next day looked around. Removed rh valve cover and found this.. Frowner

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Where's the valve?

427 Fords were notorious for dropping exhaust valves due to the sodium filled stems fracturing.

I never heard of 351c's being particularly susceptible to this but there are now so many aftermarket components going into them durability is becoming a bigger issue than ever.

A failure like this USUALLY takes out the piston, the connecting rod (gets bent) and the cylinder head combustion chamber gets pound on by the valve and destroys it?

The D2AE-CA blocks are thin enough that often the bore cylinder cracks as well.

Nope. This one isn't going to polish out. Roll Eyes

Sorry to hear of your troubles.
No valve to be seen, one of the CompCams valve locks was broken in 2. These are PAC 1255X-16 Racing RPM series beehive single springs, OD 1.445”, ID 0.731”, max lift 0.70”. Spring height is great, no spring bind, not near hitting the valve seal. A few gouges on the bottom of the Yella Terra rocker but spins nice still.

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Interesting. It's better than I would have thought?

Compcams is one of the companies I am having issues with because they have virtually no quality control checking.

They won't tell you where the components are made and it certainly isn't by them.

All the old "texts" of how the American "engine builders" would use various methods for checking components to me just comes home to roost now?

None of these companies want to pay for a human to do quality checking.


My story of Carrier (air conditioners) having a 50% failure rate at start up just keeps coming back.

The company went non-union and "off shore" to reduce production costs. Before they were in a 10 to 15% failure rate.

Doesn't make sense to me unless they are just dumping responsibility on someone else?

Compcams just dumped it on you?
The camshaft has grooves, difficult to say if how bad. Comp Cams custom mechanical roller camshaft, Grind# FC2314F/2318FR110
Duration @ 0.050 250 Intake - 258 Exhaust. Gross lift 0.640”, Lobe separation 110.0
 Cam in @ 105 1/2 cl. 
Crower 66218E Enduramax Solid roller lifters with needleless roller bushing
 look good and spin nicely. The pushrods roll nicely so might be okay, CompCams Hi-Tech 3/8" 0.080" seamless wall.
#4 bore has 2 small dents from the valve head / stem. In the picture of the head you might be able to see the gouge the valve stem made as it was pounded out of the intake port. Aluminium is in combustion chamber and intake manifold.
Engine is now out and will be crated up to send back to Kuntz and Co who built the engine, 1 year, ~2,000 miles ago.

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I have been in contact with Scott Cook who made the heads and intake. He said he will repair and re-cnc the head. I will send the head and engine to Jim Kuntz and let him repair it, he has the expertise and hopefully quicker when adding in the shipping time to Australia. I did not have any oil or water leaks, oil in water or visa-a-versa. The Mahle piston can be replaced and hopefully the block saved, my original 15,000 mile-r.

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I feel for you... So sorry to see this. Looks like what happened to my fresh engine after only 980 miles or so. PAC Beehive spring broke and dropped the valve because the beehive springs have no damper to retain the valve if the spring or keeper fails. The RCA on my engine revealed some of the valve springs were out of spec, meaning they reached a coil bind situation with my cam even though my cam lift was well within the advertised capabilities of the springs.

Be sure your engine builder checks the compressed spring height of each spring. Your Beehive springs have advertised specs of:
Max Coil Bind: 1.210
Max Lift: .700
And your cam has 0.640” of gross lift. It would appear you have a sufficient safety margin, but everything's gotta be checked. I thought the same thing with my beehive springs and lift and trusted the advertised spec for the valve springs without measuring each one, so I ran into a coil bind situation with my engine.

Good luck, and keep us posted.
THANKS for posting the pictures & relaying the conditions found.

A GREAT reminder as per Garth, Doug's & many other experiences is that ...DON'T TRUST ANY advertised specifications, seemingly & SADLY quality is a long forgotten memory, & an individual's due-diligence & personal inspection, measuring, testing of each & every individual component is mandatory!...Mark
quote:
Originally posted by 1Rocketship:
THANKS for posting the pictures & relaying the conditions found.

A GREAT reminder as per Garth, Doug's & many other experiences is that ...DON'T TRUST ANY advertised specifications, seemingly & SADLY quality is a long forgotten memory, & an individual's due-diligence & personal inspection, measuring, testing of each & every individual component is mandatory!...Mark


While I agree that the assembly of the valve train needs to be checked at each and every step of assembly, that is doable and necessary by me or your builder, it is not possible during that assembly to verify BY ME (or your builder) that each and every component meets the minimum specification that the manufacturer intended. The manufacturer HAS to do that.

This has become even more of an issue now with attempts at much higher horsepower engines and as a result coming closer to the ultimate yield stresses of ALL of the components.

These are nothing less than ultimate race engines being put into street use and they have even under the best conditions a much shorter usable life span.

The answer is to just back off on some of these components like solid roller camshafts.

No one seems to heed the cautions? Now everyone has me reviewing my own valve train and cam specs?

Solid roller camshafts on the street are just disasters waiting to happen. The disaster IS going to happen. The only question is when, where and HOW bad? I just see them as a common denominator to be avoided.

Again. I am sorry for the loss. This just plain sucks.
Can you please elaborate on why solid roller cams are disastrous?

If the lash is checked regularly, shouldn't they last?

I can totally understand there being a "finer edge", like if not adjusted properly or allowed to have enough lash to start hammering stuff, but why else is solid roller so bad for the street?

My engine is a case example here as we all know, but I think there were some other factors in play in my engine's case (like abuse, and overreving, and age).

I always thought the main difference between solid and hydraulic was solids were capable of more performance (higher rpm's), but needed to be regularly adjusted, religiously.

What else about solid roller cams is so bad?

Just more stuff to go bad?

What about the solid roller cam on Bdud's engine caused this failure?
I think there is too much weight to the valve train. Too much "mass" to be technically correct.

If you look at bdud's cam lobes, they are already scoured. At what, 1,000 miles?

Show me someone with profiles like the two of yours that has got some real miles on the engine and doesn't need to keep going under the valve covers after every run.

Do you think you are imagining this? What is the common denominator in both engines? Maybe the cam?

I suppose that I am just old, old school but I feel there is no place for a roller cam like those on the street?

Those are just "Pro-street" engines and need the maintenance of a Pro Stock race engine. What's the point?

Just my perspective. It doesn't mean I am right. It does mean I was entirely right (for me) in staying with a flat tappet, solid lifter cam. I understand that one.

I don't understand why these solid rollers fail at all, but to me, it's undeniable?

How many miles did Roger say he had on that engine?


If that was my engine, that cam would have been long gone. My neighbor would be lucky not to find it thrown over the fence. I am not as patient with this stuff.
I didn't have the opportunity to spec my engine out, so I'm stuck with what I bought.

I can see what you are saying though. Mainly people are building race engines for street use, and race engines, while they make more power, burn out faster. Is that it in a nutshell?
quote:
.... race engines, while they make more power, burn out faster. Is that it in a nutshell?



I don't have a race engine, but I have to throw in this quote from Blade Runner...

".....The light that burns twice as bright burns half as long - and you have burned so very, very brightly, Roy Mike" (and BDUD)


I loved that movie!

Rocky
Relatively speaking, Extreme valve spring pressure & severe camshaft profiles/ramping are kryptonite to Superman's engine.

That is why exotic engines utilize dual overhead camshafts per cylinder head & 4 valves per cylinder to eliminate the necessity of having to resort to extreme valve spring pressures & HUGE camshaft profiles to develop 2HP per cubic inch of displacement ratios at the sacrifice of engine longevity ...Mark
quote:
Originally posted by Rocky:
quote:
.... race engines, while they make more power, burn out faster. Is that it in a nutshell?



I don't have a race engine, but I have to throw in this quote from Blade Runner...

".....The light that burns twice as bright burns half as long - and you have burned so very, very brightly, Roy Mike" (and BDUD)

Rocky
GREAT MOVIE!!!...& I will add like the eventual end of a HIGHLY Stressed Race Engine..."Time to DIE!!!"...Mark

https://www.youtube.com/watch?v=HU7Ga7qTLDU
They (many race engines) are very streetable IF you do the maintenance to them they require BUT the part consumption rate is not predictable.

I would say that you are living that proof. You are also PRESUMING that the former owner did not go through this as well? I think he did.

I keep saying this over and over and over, people just do not understand the nature of this "kind" of engine. THIS IS IT...and, you don't even know the condition of the valve springs.

Those are just ticking time bombs.

VERY, VERY, VERY simple solution. Change the camshaft. Put something more reasonable in there. Even a flat tappet solid lifter with similar timing will give you more of a safety factor then the roller lifters will.

Let the engine builders who disagree, and want to sell you their version of this engine guaranty the thing. Then watch them change their tune.

Otherwise...

"Bada-boom...BIG BADA BOOM.

https://www.youtube.com/watch?v=j8WLYzA0lCs

Go with your plan A now I suppose? Run it until it breaks...again. Then go to plan B...whatever that is?


I remember a comment Elvis Presley made at the Arizona Monument news conference back in 1970 or so. Someone asked him what would he do if he found out that "it was all over for him?" He answered, "just say I've had my day and get on with it?" I guess that's true for all of us at some point?
She is so HOT! Especially in that orange "body thong" thing they had her wearing in that show.

https://www.youtube.com/watch?v=j8WLYzA0lCs

At this point, I agree with you doug, not arguing at all.

It's just I'm tapped out. I overspent on the car (thought I was getting a solid, reliable car though) and have spent months of time and money just to get it back running.

Since my car is devalued until I install a new or rebuilt engine, I see no reason to spend any extra money on it at this point (save for a tune, and that it stays running). I'm saving to rebuild it next year.

The new engine will be specifically built with knowledge I've obtained from you and others here on this forum, and will be spec'd out to make big power but also last a long time.
quote:
Originally posted by mike the snake:
She is so HOT!

The new engine will be specifically built with knowledge I've obtained from you and others here on this forum, and will be spec'd out to make big power but also last a long time.


Now that you have had a taste of the forbidden fruit - can you ever be satisfied with anything less?
quote:
Originally posted by mike the snake:
She is so HOT! Especially in that orange "body thong" thing they had her wearing in that show.

https://www.youtube.com/watch?v=j8WLYzA0lCs

At this point, I agree with you doug, not arguing at all.

It's just I'm tapped out. I overspent on the car (thought I was getting a solid, reliable car though) and have spent months of time and money just to get it back running.

Since my car is devalued until I install a new or rebuilt engine, I see no reason to spend any extra money on it at this point (save for a tune, and that it stays running). I'm saving to rebuild it next year.

The new engine will be specifically built with knowledge I've obtained from you and others here on this forum, and will be spec'd out to make big power but also last a long time.


Well Scott Fuller is going to repair those heads for bdud AFTER he sends them back to Australia at his expense.

The fortunate part is that that head CAN be repaired.

Yours are Ford Motorsport/racing heads of the "Yates type".

Neither Ford OR Yates is going to make you the same offer for the heads.

Who is going to fix the block when you crack the wall, replace the piston, unbend the rod and the crank?

All considered I'd say the better deal is to pull off the heads, change out the springs, put a solid lifter cam in.

If you are going to need to wear diapers while driving this car it should be because it is too fast and not too fragile.


Yes. Mila has got it going. She's actually much hotter in person but her body guards are trigger happy. Don't get too close to her if you see her on the street. Just yell at her "ecto gammit" (never without my permission). She'll get it and maybe even wink at you?

Not to be judgmental but tangerine really isn't her color?
Hello Mike; Here is a suggestion ( OHHHHH NO!!!) that will dramatically increase the longevity of your existing valve train.

Question you need to ask yourself..."Do you want/need your current engine to rev to 8,000 RMPS??!!

If the answer is a resounding NO!!!

Then consider just replacing the existing springs with a set measuring considerable LESS "Fully Open Valve Spring Pressure".

Your current FOVSP is calculated on your engine revving to 8,000 RPMS.

Would you be satisfied with a Redline of 6,000-6,5000 RPMS?

Without knowing your exact FOVSP, I imagine by changing from a 8,000 RPM Redline to a more conservative 6,000-6,500 RPMs redline could reduce the valve train stress/wear by at least a 100 ft lbs.

You could still utilize your current camshaft.

At the worse by going to less FOVSP with the current cam, you could experience valve spring float at higher RPMS, which is like a built in over rev indicator Smiler

I would be Extremely curious if your engine is still building horsepower beyond 7,200 RPMS!...Mark
Oh Hell no! The new engine will probably make even more power! LOL Probably twin charge it, twin turbos with an 8-71 on top sounds about right. I'd have to modify the upholstery and rear window a little to clear the blower belt lol.

I should be able to make all the power I need without having to spend an exorbitant amount of money on my valvetrain, because I won't need to rev it so high! LOL

Honestly, I'm not sure what I'll build it into. The power IS addicting, but I KNOW I don't use all 650 HP, and I know I'd be happy with less.

1Rocketship, thanks for the suggestion. In my care the engine won't see 8000 rpm, i know this for sure, especially since my tach doesn't work, but I just don't rev my stuff that high.

Maybe if I can figure out how (or find someone who can help me) to tune my ancient Haltech ECU, (I've been told it IS possible) I can set a reasonable rev limit.

The car is running acceptably at present, albeit very rich. It WOULD be nice to actually get a real tune, but next year the electronics are all getting upgraded anyways, so again, how far down the rabbit-hole do I want to go before I get to rebuilding?



quote:
Originally posted by Rocky:
quote:
Originally posted by mike the snake:
She is so HOT!

The new engine will be specifically built with knowledge I've obtained from you and others here on this forum, and will be spec'd out to make big power but also last a long time.


Now that you have had a taste of the forbidden fruit - can you ever be satisfied with anything less?
Hello Mike; Since you are NOT using the 8,000 RPM capabilities of your engine & would be satisfied with a 6,000-6,500 RPM redline.

I would eliminate the "Extra" valve spring pressure that your engine currently has that allows it to rev to 8,000.

I would be VERY INTERESTED, what your engine dynos at 6,000-6,500 & then at 8,000??

If the difference is 100 HP ( guesstimating) would you be satisfied with 550 HP, if it meant increasing the longevity of your engine, exponentially???!!

As an example...If your current 650 HP engine would last 2,500 miles before a mandated teardown vs a 550 HP engine that would last 7,500 miles before a mandated teardown...

Which would be your choice ??!! ...Mark
It may be, i was told it's a 408 now. I was told it had a Scat crank, I'm assuming it's a stroker crank, Scat rods, big balancer, Ross pistons, all the goodies.

Next year I'll have the entire block checked, along with everything else. The engine i plan to rebuild/blueprint to new/like-new condition.

I'm planning on upgrading the electronics as well, to control both timing and fuel (presently my Haltech only controls fuel).
quote:
Originally posted by 1Rocketship:

I would be Extremely curious if your engine is still building horsepower beyond 7,200 RPMS!...Mark



The Yates heads typically continue to make power to the limit of the engines rpm capabilities. Definitely to at least 8,200 but that is the practical limit (for me).

You need to reduce valve train inertia to reduce spring pressure requirements.

The roller lifters add to it as do the large Cleveland valves.

Titanium valves help but don't have the same longevity of the stainless/chrome valves. I actually would not be shocked to find titanium valves in this assembly?



Hydraulic roller lifers have been in use for some time in OHV updated Chevys and Fords but for emmissions reasons and typically aren't set up for much over 6500 or 6600 rpms if even that?

Over head cam engines don't need to worry about these issues any more.


There are other issues too with the need for 3/8" push rods vs 5/16. Adds inertia. Incidentally, so does 40 weight oil.



I don't know if there is enough documentation around by ANYONE that will give an accurate guide on exactly how solid roller lifter valve trains can relate to zero maintenance and actual mileage projections for zero maintenance? If there is, show me, I want to read that?

Everything I am seeing is that they just require almost constant maintenance on them just like a Pro Stock drag race car does, virtually after every run.

Granted Pro Stocks are leaving the line in the 9,000 rpm area and this engine isn't. How that translates into less maintenance I don't think ANYONE can explain adequately?

A much simpler solution is to switch to a lower maintenance set up, but I suppose that happens more so involuntarily than any other way?



As far as the Yates heads practicality? Well. My A3 heads (the Yates heads are a later evolution of the Ford aluminum race heads started as replacements for the iron Cleveland and Boss 302 heads) flow on the intake 330 cfm at .630 lift.

The Yates heads, about 380 at the same lift.

If you cross reference that flow to the ability of 357 cubic inches to pump that, the engine is in the 10,000 rpm range in order to use it.

The flow graph is almost a perfect straight line as far as flow vs. lift. Theoretically you can just pick your spot where you want to limit it to with cam lift and you are done.

Well sort of. The Yates heads intake ports in particular are not just big holes in an aluminum casting, their forte is getting the flow by accelerated air velocity through the ports. Cutting the lift also CAN cut the velocity through the port. That change isn't necessarily going to be a straight line curve? That means the Yates head works better at very high lifts, very high velocities, probably much better than an iron head would at lower lifts but only a percentage of flow that you would think it should?



Iron heads have been shown (by Dan Jones) that with a nice valve job flow right around 300 cfm (298 is what Dan's flow bench showed). That's a very nice number for a street engine. He didn't mention velocity with them though.



So really the answer with those Yates heads is that yes they really do make actually 700 to 750 hp out of 357 cu in but at race lifts and rpms. The horsepower curve is pretty much a straight line straight up into the stratosphere.

Turning the engine to 8,200 rpms is VERY DIFFICULT to resist doing. The engine makes such wonderful sounds!



The profile of the camshaft that MTS has in the engine, simply put, compliments those heads.

On a street engine, a different head might be a better consideration? Maybe?


Anyway, those heads definitely do make the power and that and a $15 toll will get you over the Verrizonos Narrows Bridge into Staten Island. Look out for the pot holes. They are free.
Well actually it's free to get into Staten Island. You have to pay to get out.
I know, I felt bad too about the thread going so sideways!

How is the block? Was it damaged? The heads and manifold can be welded and remachined correct?

If the rod got bent, then I'd suspect a complete inspection of every part on the engine is in order, block and crank checked for cracks, crank checked for trueness, the whole nine yards.
quote:
Originally posted by Rocky:

Howzabout back to BDUD.....Any updates? Or is everything out of the car, and on it's way for refurb? Good luck on the reconstruction. If you post up a reassembly thread - we promise we won't hijack it next time....

Back to Topic

Rocky

"we"?



I meant the "Royal 'We'"

By which I mean "You"

(JOKE) Cool
quote:
Originally posted by Rocky:
quote:
Originally posted by Rocky:

Howzabout back to BDUD.....Any updates? Or is everything out of the car, and on it's way for refurb? Good luck on the reconstruction. If you post up a reassembly thread - we promise we won't hijack it next time....

Back to Topic

Rocky

"we"?



I meant the "Royal 'We'"

By which I mean "You"

(JOKE) Cool


Ha! I already tried that here.

This is the most undisciplined forum I've ever been on. Even the OP's here hi jack their own threads!

I do understand that though. For instance, MTS has got so many posts going here, he can't remember which one to post the latest disaster into! (no offense intended Mike)
No offense taken!

I just have had a LOT happen in a short period of time, and lots of questions, and this is a particularly quiet forum. I'm just livening things up a bit! lol

This is the best forum I've had the opportunity to participate in.

Thread jacks and threads going sideways is just a part of forums, but how people behave and react here is what makes it so great.

Lots of good people here.

OP, please keep us posted on any progress or repairs, I know I'm genuinely interested.



quote:
Originally posted by PanteraDoug:
quote:
Originally posted by Rocky:
quote:
Originally posted by Rocky:

Howzabout back to BDUD.....Any updates? Or is everything out of the car, and on it's way for refurb? Good luck on the reconstruction. If you post up a reassembly thread - we promise we won't hijack it next time....

Back to Topic

Rocky

"we"?



I meant the "Royal 'We'"

By which I mean "You"

(JOKE) Cool


Ha! I already tried that here.

This is the most undisciplined forum I've ever been on. Even the OP's here hi jack their own threads!

I do understand that though. For instance, MTS has got so many posts going here, he can't remember which one to post the latest disaster into! (no offense intended Mike)
I shipped my engine out and it arrived at Kuntz & Co Friday. I will post an update on its prognosis. The broken valve spring should not have happened, everything was in in spec, I checked before I sent it off.
My engine was designed for a 6,700rpm limit and that is what my limiter is set for.
Comp cams only list 2 roller mech street cams for a 351c, I had a custom spec which was built between the 2.
I use 10w30 as per the builders recommendations.
The only camshaft lobs with marks were on cyl#4, the one with the rough time.

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quote:
Originally posted by bdud:
I shipped my engine out and it arrived at Kuntz & Co Friday. I will post an update on its prognosis. The broken valve spring should not have happened, everything was in in spec, I checked before I sent it off.
My engine was designed for a 6,700rpm limit and that is what my limiter is set for.
Comp cams only list 2 roller mech street cams for a 351c, I had a custom spec which was built between the 2.
I use 10w30 as per the builders recommendations.
The only camshaft lobs with marks were on cyl#4, the one with the rough time.
Is your engine in the crated box or a baby elephant?!...Mark
I used the same crate when the engine was shipped to me. Engine was mounted on engine stand with lift plate on top. In the crate is a pair of Pat Mical's headers with my MSD Atomic EFI for use on the dyno after its resurrection.
I have the dyno charts when they tested it before, gts / dyno headers, 650dp / dyno carb. I will post these in the 'dyno numbers' thread when I get a chance.
Not sure how much a small elephant weighs but my package was 400lbs according to fedex.
For future reference,
There's an outfit for shipping large items called "Forward Air". They have depots near every airport, but do NOT do door-to-door.

The price difference was HUGE for the package I wanted to send (like $85 instead of $1500).

I used them maybe 20 years ago, I'm sure they're still around.
I have used Forward Air before, their closest location to me is over an hour away, so 4 hrs plus for taking there and picking up. Then paying for someone to deliver at the other end & collection.. I have used a couple of other shipping companies but there is quite a lot of value wrapped up in that crate.

If this had happened just a month ago I would have driven the engine down to them. I flew into Little Rock to buy a half started prostreet/restomod 1966 Mustang Convertible which we trailered back and I am working on. The one way air ticket to Little Rock was $490...
It cost $600 when the engine was shipped to me before but the pallet was taller and had a lot of stuff in there, it also weighed 700+ lbs.
Hello bdud; Readily appears that Kuntz & Co definately has the correct approach!

I REALLY LIKE the idea of the engine returning to you, broken in on the dyno, precisely tuned & ready for installation

Have you also had modifications/upgrades to the ZF to handle the 650dp?

Are you utilizing upgraded half-shafts & U-joints?


Does Kuntz & Co provide a video to the customer(you) during the engine break-in & dyno tuning?

Would be VERY interesting in my opinion to visually witness the progression of horsepower as the engine is "Dialed-In!

Will the engine use pump gas or need higher octane fuel?

When the engine crate returns...Christmas DEFINITELY Cheers comes early!!!...Mark
quote:
650dp / dyno carb

I meant 650 double pumper, :-)
The engine made 626hp @ 6,700rpm, 557lb-ft @ 4,900rpm with dyno carb and headers but 552hp @ 6,200rpm, 505 lb-ft @ 4,800rpm with the MSD Atomic & GTS headers. Initial runs were with race gas they then used 93 octane which is common here. Hopefully they can tweak it a bit with Pat's headers. I am more than happy with the 550hp as that was what I asked for..
No mods to the ZF, I hear they are pretty tough.
I do have CV half-shafts.

Here is one video they sent me with the GTS headers. http://f.cl.ly/items/3624242n2...20j350o/IMG_0996.m4v
I have many run sheets.
Hello bdud; Have you considered running 180 headers?

TOO Bad, you couldn't have run the engine with the 180 headers on the dyno, to see the possibilty for increassed HP & torque & smoother idle.

I ENVY those engine building television shows, where the engine builders freely swap out carbs, headers, cams, heads,etc,etc, change timing to see the different HP & torque gains ( or NOT).

With the ability to purchase that "Race Gas" product...

http://www.maperformance.com/r...5-Aa0hEKoxoCFonw_wcB

having the ability/ies to customize the octane rating for various HP requirements is quite advantageous/beneficial...Mark
I have no interest in running 180's, like the idea of having luggage space.
The engine runs on 93 octane which is readily available in MA.
6,700rpm rev limit.
Jim's guys have stripped the engine, welded and replaced the intake valve seat & re-cc'd the ports and chambers. New intake & exhaust valves (1 of each) & 1 piston ordered. Other head stripped also, cam, roller followers all checked, all ok. Going to Manley Nextek dual valve springs. Engine being built back up, hopefully it will come home soon.
Nice dyno numbers. They did not tune it, used a "dyno" carb and Pat Micals headers.
With the dual Manley Nextel valve springs they had a slightly higher rev range which was more stable compared to the PAC single conical springs.
639.7hp @ 6,600rpm (can I call it 640hp?), 531.2 lb-ft @ 6,000rpm. My previous best run was 626hp @ 6,700rpm & 556.9 lb-ft back in Dec 2013, same cam etc. They hope to ship out tomorrow, possibly Monday. Smiler

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quote:
Originally posted by 1Rocketship:
Being that the engine NEVER came UP to operating temperature ( 126 F)

I state there is a few EXTRA Ponies at 200 F.

What was the octane rating of the fuel & total degrees of advance?

Very MUCH appreciate you posting the dyno #s Thank You Sweet...Mark


Yes, too cool is giving away power but the oil temp is what you want.

That temperature can actually be determined on the dyno.

Every engine will have an optimum operating temperature. That's difficult to determine on the street. You would be just guessing at it.

Given the change with good air, bad air, you could be crediting the hp increase to the oil temp and in reality it could be a good air situation.

More than 25hp is created by cooler dry air...and about another 25hp is there for the taking with maintaining about 10 inches of vacuum in the crankcase under power.
quote:
Originally posted by PanteraDoug:
quote:
Originally posted by 1Rocketship:
Being that the engine NEVER came UP to operating temperature ( 126 F)

I state there is a few EXTRA Ponies at 200 F.

What was the octane rating of the fuel & total degrees of advance?

Very MUCH appreciate you posting the dyno #s Thank You Sweet...Mark


Yes, too cool is giving away power but the oil temp is what you want.

That temperature can actually be determined on the dyno.

Every engine will have an optimum operating temperature. That's difficult to determine on the street. You would be just guessing at it.

Given the change with good air, bad air, you could be crediting the hp increase to the oil temp and in reality it could be a good air situation.

More than 25hp is created by cooler dry air...and about another 25hp is there for the taking with maintaining about 10 inches of vacuum in the crankcase under power.
I'm going to install a T fitting in the PVC line from the valve cover to the carb base & install a vacuum gauge to measure the amount of vacuum the engine has under power...Mark
The gauge has to go on the air intake side valve cover. The opposite of the pcv cover.

You want to read the vacuum in the crankcase, not the intake manifold. That's the closest place you could read it.

You could also hook it up to the oil dipstick tube...without the dipstick of course.

At idle it doesn't matter too much. A good pcv valve like the M/E Wagner is set out of the box for 0 to .5. It's also the only precision pcv valve that I know of.

You want to see 10 or so under power. 12 will be too high and suck the oil seals in. Even 8 would be fine.

If by some chance your crankcase vacuum is too high, you can adjust it down with the m/e/ wagner unit.

The now old style header evacuation tubes produced 3-4 which is not really enough.

The theory is that the vacuum helps seal the top piston ring better.

Nothing is a perfect design, it's just that this is 25 free hp. Lots of people give that away.
I have not got the build sheet, it is coming with the engine. I think they used race gas, 110+ octane, as the main intention was to verify everything and check for leaks. Last time they used 93 octane for the last runs as that is what I am using. Same compression ratio, camshaft etc as original build so the fundamentals have not changed. 30 degrees total timing was used which was determined during the original build.
quote:
Originally posted by bdud:
I have not got the build sheet, it is coming with the engine. I think they used race gas, 110+ octane, as the main intention was to verify everything and check for leaks. Last time they used 93 octane for the last runs as that is what I am using. Same compression ratio, camshaft etc as original build so the fundamentals have not changed. 30 degrees total timing was used which was determined during the original build.


Some of the racers have been using 30-32 total advance on the track even though many of the engines were set up and tested with 35-36 on the dyno.
quote:
Originally posted by PanteraDoug:
The gauge has to go on the air intake side valve cover. The opposite of the pcv cover.

You want to read the vacuum in the crankcase, not the intake manifold. That's the closest place you could read it.

You could also hook it up to the oil dipstick tube...without the dipstick of course.

At idle it doesn't matter too much. A good pcv valve like the M/E Wagner is set out of the box for 0 to .5. It's also the only precision pcv valve that I know of.

You want to see 10 or so under power. 12 will be too high and suck the oil seals in. Even 8 would be fine.

If by some chance your crankcase vacuum is too high, you can adjust it down with the m/e/ wagner unit.

The now old style header evacuation tubes produced 3-4 which is not really enough.

The theory is that the vacuum helps seal the top piston ring better.

Nothing is a perfect design, it's just that this is 25 free hp. Lots of people give that away.
Some many thoughts swirling around my little walnut>>>

With Bud having a Brand New & properly broken in /sealed piston rings.

I wonder what Bud's crankcase vacuum is?...&...What is Bud's Breather vacuum?

...What is the two vacuum's differential numerically?!...Mark
quote:
Originally posted by 1Rocketship:
quote:
Originally posted by PanteraDoug:
The gauge has to go on the air intake side valve cover. The opposite of the pcv cover.

You want to read the vacuum in the crankcase, not the intake manifold. That's the closest place you could read it.

You could also hook it up to the oil dipstick tube...without the dipstick of course.

At idle it doesn't matter too much. A good pcv valve like the M/E Wagner is set out of the box for 0 to .5. It's also the only precision pcv valve that I know of.

You want to see 10 or so under power. 12 will be too high and suck the oil seals in. Even 8 would be fine.

If by some chance your crankcase vacuum is too high, you can adjust it down with the m/e/ wagner unit.

The now old style header evacuation tubes produced 3-4 which is not really enough.

The theory is that the vacuum helps seal the top piston ring better.

Nothing is a perfect design, it's just that this is 25 free hp. Lots of people give that away.
Some many thoughts swirling around my little walnut>>>

With Bud having a Brand New & properly broken in /sealed piston rings.

I wonder what Bud's crankcase vacuum is?...&...What is Bud's Breather vacuum?

...What is the two vacuum's differential numerically?!...Mark


Racers are using mechanical vacuum pumps to scientifically provide a steady constant vacuum.

I think that is a more reliable way of providing consistent vacuum to the crankcase than taking it off of the intake manifold.

Individual runner manifolds are not the best sources of engine vacuum for one thing. Single plenums provide more volume of vacuum.

However the crankcase doesn't need exorbitant volumes. One 3/8" fuel line seems to be fine.

My car is a work in progress in that respect. I may need to go to a separate electrical vacuum pump on the car. Certainly to get a NASCAR type mechanical pump working of the crank pulley isn't a slam dunk. I can't find a place to put it?

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