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Yep, it was the oil pressure gauge. I haven't pulled the distributor out yet but the motor sounds normal when it turns over however the rotor doesn't turn so I am pretty sure that is the problem. The funny thing is, I read about this issue when I built the motor so I did double roll pin the gear but I am thinking that maybe the roll pin I used wasn't hardened. What do you think? Are there different strength roll pins?
The motor is a 351c, 30 over with 4v open chamber heads. I used pop-up pistons to bring the compression ratio up to around 10.5 to 1. I used a Lunati hydraulic cam that has .565 lift on intake and .588 lift on exhaust. The advertized duration is 300 intake, 310 exhaust. 234 intake and 244 exhaust at .050 tappet lift. It pulls pretty good until about 6000rpm.

Yes, mostly 3rd and 4th for the whole track. 2nd a couple of times but as I become a better driver maybe I wouldn't need 2nd. Smiler
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maybe the roll pin I used wasn't hardened

Scott,

You may have gotten a Chinese roll pin, or your oil pump may have sucked up a piece of something that was in the oil pan. If the pin were too hard, it would be brittle and shatter easily.

Try looking for a roll pin at an aircraft parts supply. All of the aircraft parts are supposed to have traceability. Try Aircraft Spruce. They are located near you in Corona.

A spiral roll pin is available. McMaster-Carr has them, but I don't know where they get their pins.

John
Scott, there are other possibilities which you'll find when you pull the distributor. First and most common is the roll pin. I've not heard of a double roll pin breaking so it may well be one of the others. #2 is breaking the pump driveshaft between the pump and distributor gear; hardened drivershafts are less than $15. #3 is actually shearing badly worn gear teeth off the distributor drive from a couple of causes, one of which is metal incompatibilty and the other is a cam with its integral gear cut on the wrong tooth-angle. The last has happened from all known cam grinders since they all buy cam-blanks from one of only about 3 manufacturers. I'll be waiting to find what the root cause actually was. On the good side, if dropping the pan and checking #1 or #2 rod bearing shows only light bearing wear, you dodged a bullet. Good luck-
Well, I pulled the distributor out today. It was extremely difficult to get out. The double roll pins held. The gear however didn’t do so well. The gear had broken teeth. There appears to be slight damage to the cam gear so I guess I am going to have to change the cam.

The bottom of the distributor shaft has several hairline cracks around where the oil pump drive shaft inserts. The top of the oil pump drive shaft looks damaged and doesn’t look centered in the hole. I have an oil pump prime tool that will not engage the oil pump drive shaft so there is definitely damage in that area.

So the question is what happened. The motor only has about 3000 miles on it. The oil pump was new, cam was new, oil pump drive shaft was new. If the oil pump sucked up something where did it come from. Could the shaft at the bottom of the distributor have cracked first and seized in the hole?

I guess I am going to be pulling the motor out…
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If the oil pump sucked up something where did it come from

It could have been any number or things including (but not limited to) a small piece from a gasket, a hardened piece of sealer, a small piece from the distributor gear or cam gear. When you get the oil pump out and apart, you should be able to tell.

One of the problems with increasing the distributor's roll pin shear value is that it won't shear easily should something get sucked up into the oil pump.

John
A few possibilities:
1- If you've recently changed distributors from any source, be aware that a 351W distributor WILL fit in a 351C..... but the smaller diameter Windsor gear will only engage the outer 0.060" of its teeth on a 351-C cam. This may (if you're lucky) last for 200 miles before the gear teeth on the distributor rip off.
Second possibility: some aftermarket cams were made with the 'pressure angle' of the distributor gear on the new cam ground at the wrong angle. The result is, the distributor gear teeth fail; one wore to razor thickness in only 5.0 miles.
Third: there is an oil passage in the front of the block that comes off the second drilling of the front cam bearing. If the front cam bearing is installed wrong, that passage will be blocked and no oil will squirt onto the distributor gear/cam gear mesh. I have heard of distributors siezing from lack of this oil.
4- engines that run high pressure or high volume oil pumps put far more load on the distributor gear than a std pump. In some cases, this is enough to radically increase gear wear.

All these scenarios will pump metallic slop through the engine and do bad things to bearings and the oil pump. It may be a good thing to drop the pan and check #1 or 2 rod bearing (most likely to fail in a Cleveland), #1 main bearing, the crank journals on those bearings checked and the oil pump body, all for deep scratches.
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So whats the problem?

I have no clue what caused the problem. Something got into the reciprocating area at the front of the motor and did extensive damage. I found this in the bottom of the oil pan...

I have gone over EVERY part with a fine tooth comb and cannot find where this metal came from. Mad

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Here is my guess:

Bigger: The modular engines are Bigger because of the heads. They are not bigger from a displacement point of view

Better: The modular engines are Newer in design and construction - arguably better. A tuned 4.6 DOHC will give you over 350hp SAE NET and/or about 300hp at the rear wheels.

Faster: The modular engine generaly revs higher than a Cleveland (although that depends). O-60 times can be faster depending on what Cleveland you are comparing to.

All Aluminum V-8: The earlier 1996 thru 2001 4.6 DOHC Cobra engines were All Aluminum. No 5.4 DOHC engine was aluminum except for the Ford GT engine (but that does not fit well).

Computer Controlled: Modular V-8 will do.

ZF Transaxle: Bolts right up to a Modular - Non Ford block engines will require some mods or a different bell housing.

Fits Better than the 351C: 4.6 DOHC modular just drops right in a '73-74L car under the engine screen and you get a flat firewall !!

Sounds like a 4.6 DOHC , Starts like a 4.6 DOHC

I have seen 4.6 DOHCs in DeTomaso's. I have driven one. I am installing one.

My Guess is a Cobra based 4.6 DOHC 1998 to 2001 Modular engine. The engines were made to race.

B.G.
Last edited by andriyko
Wow Andriyko,

That was very well thought out. I like how you put a lot of thought into your guess. You hit every point.

Now for those that think that we shouldn't modify our cars, please stop reading this now. For those that think Ford is our only option, stop reading this now.

For those with an open mind I hope you find my change as cool as I do.

The engine I decided to go with is 480hp right out of the crate. (and only 410 pounds complete)

http://www.youtube.com/watch?v=VgU_S5Wr7yw

Great guesses everyone...
Scott Bell

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Now for those that think that we shouldn't modify our cars, please stop reading this now.


I have NOT seen an unmodified DeTomaso Pantera. It is all a question of degree.

Great work on the engine swap. Congratulations.

There is a long and ongoing discussion on replacement engines for our Pantera's. There are many great engines available that would fit and do the job. Which one someone choses is a matter of personal preference.

B.G.
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Other than electrics, what were the most difficult parts of this swap?

Jack


I guess the hardest part was turning the intake around. There was an oil sender boss that needed to be milled off and plugged so the intake could be reversed.

The other item was making a new cross member.

But to be honest, it was a pretty easy swap.
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More pictures!!


I am having my son post a photobucket on the project. He should have it done today.

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More details!!!


The motor is an LS376/480 crate motor. 6.2 Liter All Aluminum V8. It is based on the LS3 Corvette motor but has a hot cam installed. It has 10.7:1 compression and has 480HP at 5750RPM. It has 475(lb-ft) of torque at 4500RPM.

What is cool about this motor is the amount of torque it has. It pulls strong in every gear. It has 400(lb-ft) of torque at 2500RPM.

I can be rolling at 10MPH and give it half throttle and it breaks the tires loose.

It is so much more fun to drive then it was before.

I can run an almost flat firewall and access to every part of the motor is much better.

Part of the benefits of this package is the front drive that included a 150AMP Alternator that is controlled by the computer.

Scott
Put almost 200 miles on the car this weekend. Not a single problem.

The car runs so cool the computer doesn't even turn on the radiator fans for almost the entire drive.

The torque of this motor is incredible. And it runs like a factory 2010 car.

I also added a nice stereo system with a 160watt amp and an Ipod interface. Next I will be building a flat firewall.
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Would like to see a list of parts used/needed for this conversion.


Here is a list short list of what was needed:

LS376/480 Crate Motor
Engine Management System with Engine Harness (comes with drive by wire pedal)
Engine Drive System (Comes with 150amp ECM controlled Alternator and AC Pump)
LS to ZF Bellhousing
Fuel Injection Fuel Pump
Flywheel
Clutch
Starter

Stuff to Fabricate are:
Exhaust
Motor Mounts
Removable Cross Member

Of course, there is a small list of other small items that also needs to be done.

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May I ask how much $ that went in this engine swap?


The crate motor was about $6500. The drive, Electronics, Bellhousing, Fuel Pump, Flywheel, Clutch, Starter, etc... was about $3000.00.

For me it worked out good as I had about a $2000.00 bill to repair the 351C. I ended up selling most of the good parts I didn’t need from the old setup for almost $3000.00 so my net out-of-pocket cost for the swap was less than $5000.00.

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You know how much weight you saved over the rear wheels too?


The crate motor was advertised at 410lbs. I am not sure how much the 351C is but it must be in excess of 700lbs if you include headers to Air cleaner.
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