Seeking advice regarding component selection for an 8 stack E.F.I. induction

 

David, your system is just beautiful. If I understand this is a "one off" manifold? I came across another manifold from a company in Australia called EFI Hardware. It also has a built in plenum. What are everyone's thoughts on this one?

 

 

Randy,

Thanks for the comment. Indeed, the carbon x-ram is a "one off". Built for the Panoz racecar from the late 90's. They did lots of experimentation on the injector placement as this can have a significant effect on performance. The intake is, as you'd expect, amazingly light!

(And the engines are from the ex-Le Mans ADA Pantera. So a big pile of interesting history there!)

As George points out, there are simple and clean solutions to provide a common vacuum signal. Personal preference, but I think these would have a better aesthetic vs the chamber cast directly into the intake. Also lighter - if that matters. Here's the vacuum set-up I use on a Ford 341:

Here's my vacuum "chamber". It's the little black box with 4 hoses going into it. Not very noticeable! Since I have four two-barrel throttle bodies (made by IPSCO), I only have four vacuum hoses. The thing with the connector on the left side of the black box is the MAP sensor. The silver thing to the right is the drive-by-wire unit. 

What would make me nervous about a cast-in plenum is, who decided what volume it should have? There's a bit of science there. The volume can have an effect on how the MAP sensor reads. If you're just running a MAP sensor, the plenum doesn't have to be very large. If you're tapping into the plenum for an IAC and/or for a power brake booster, you need a larger plenum.    

Thanks everyone for the info...I'm trying to learn as much as I can before deciding on components. Dave, are those spacers with integral injector bungs under your throttle bodies? My car is apart (and was apart when I got it) so I don't know what the dimension is between the block china wall and decklid. It seems as though Hilborn is the only available "system" but it also appears to be one of the tallest? I'm also not sure I like the concept of the throttle bodies cast into the manifold. I am willing to cut the decklid if necessary but would be happier if I could avoid it. Is the Hall manifold still being produced or are they selling old stock and is it actually available?

Yes, those are spacers that the injectors plug into. These are not off-the-shelf items; they are custom made per application. In my case, they go between the manifold and the throttle bodies. I don't see why you can't have a similar system put together using a Hall Pantera manifold vs my Kelly Coffield manifold. Keep in mind, mine is a 9.5" tall block vs. your 9.2" 351C.

This is not the way my intake was intended to be used. Normally, the throttle bodies attach directly to the manifold, then a tall K&N filter mounts on top of the throttle bodies with velocity stacks inside the filter. My EFI guru (Dave at Autotrend EFI in Northern California) suggested the configuration change and had all the custom machining done. I kept telling him it would never fit below the deck lid and he kept telling me not to worry; it'll fit! It sure helps to have a full machine shop next door! 

As an aside, Autotred EFI had an orange '74 at the shop, just before my arrival, with a Hilborn system. The system had been installed by another shop (or the owner, can't remember). They fixed the installation problems and tuned it. 

I believe Hall Pantera has new manifolds in stock. They are listed on the web-site for $900. 

Thank you again David for all the information and help. Do you think a Hall manifold with IDA throttle bodies and some sort of filter will fit under the decklid on a 9.2" cleveland?

Yes, depending on how tall the throttle bodies are. The way it's been done many times in the past, which will surely fit, would be to install injector bungs in the manifold, then use a "bungless", low-profile TB. That will fit for sure. That's the way my system was configured initially. Here's a photo. I think the air cleaners were about 2" tall. The velocity stacks are below the air cleaners. 

Thanks David, do you happen to know the dimension from the block china wall to bottom of decklid? Is the height of your throttle bodies + spacer shorter than a throttle body with integral bungs? If I used throttle bodies with the injector bung on the inside it seems like there would be a straighter shot at the intake valve. Do you happen to still have those air cleaners?

Randy, I don't know that dimension and my engine's not in the car right now, so I can't measure. I'd swear I've seen that dimension mentioned here, at some time in the past. You should be able to find a short throttle body that will work as you mention but I'm not aware of one. I seem to recall, the place in Australia that you mentioned a couple of days ago, had some. 

Yes, I still have the air cleaners in the photo. They are new and have never been used (other than to take the photo). 

davidnunn posted:

Randy, I don't know that dimension and my engine's not in the car right now, so I can't measure. I'd swear I've seen that dimension mentioned here, at some time in the past. You should be able to find a short throttle body that will work as you mention but I'm not aware of one. I seem to recall, the place in Australia that you mentioned a couple of days ago, had some. 

Yes, I still have the air cleaners in the photo. They are new and have never been used (other than to take the photo). 

Private message sent

Fitment

Any of you that use an IAC?

If yes, Is the ECU controlled by MAP or TPS then?

Yeah i would buy the minimum required hard parts from Kinsler and source the rest of the bits myself. the Holley Terminator X knocks $1.3k off by itself. everything else can be bought for less or substituted for possibly newer products for less also

I do not use an IAC. Drive-by-wire controls my idle speed. Even if I did have an IAC, I’d still use a MAP sensor only my plenum would likely be larger, so the two sensors wouldn’t interfere with each other. Some people feel that Alpha-N (no MAP sensor) is a better strategy to use with IR intakes. Others feel a blend of speed density and alpha-n is the way to go. The Holley Dominator will let you use Speed Density, Alpha-N, VE or an unlimited blend of SD and A-N. The Dominator also uses dual O2 sensors; one per side. If you want to save a few bucks I’d look at the specs for the Terminator and Terminator Max very carefully. Make sure there’s nothing you may want to incorporate in the future (eg. drive-by-wire) that one will do and the other won’t. 

Thank's for the information!

IR EFI dyno tune session: 

615.6 HP @ 6,400 RPM (617.1 HP @ 6,300 RPM w/o mufflers)

573.4 Lb/ft @ 4,800 RPM

with alternator, A/C compressor and full exhaust system, including mufflers. 

davidnunn posted:

IR EFI dyno tune session: 

615.6 HP @ 6,400 RPM

573.4 Lb/ft @ 4,800 RPM

with alternator, A/C compressor and full exhaust system, including mufflers. 

Very impressive David, what is the compression and cam specs of your engine?

Thanks. The cam is a solid roller with 280/288 duration, .636 lift and 110 LC. The rockers are 1.70 ratio T&D shaft rockers and the lifters are the new Isky EZ-Roll. The compression ratio is 11.25:1. I’m also using a poly-composite distributor gear from TriTec Motorsports. It’s supposed to be stronger than steel but more forgiving than brass/bronze. All the NASCAR teams run them and Comp Cams swears by them. It’s still plastic to me so I’ll be keeping a close eye on it! 

I've been waiting for someone to ask or mention this system that's been up on Ebay for a year or so.

It has some interesting features such as individual throttle adjustment, various head adaptability and 51mm throttle bodies.

I know of no one who has used them and the lack of mentioning the set up here kind of confirms that.

Personally I tried to get tech information on them from the seller and their response is basically, "here it is, this is it".

I presume no one here has tried it?

 https://www.ebay.com/itm/fits-...a:g:4vwAAOSwmPFchvCB

There’s a guy on the POCA e-mail forum who bought the system. I think he lives on Maui. Haven’t heard anything since he bought it but there was a lot of pre-purchase discussion. I also know a “pro” who was hired to tune one of these systems that was installed by an owner. If I recall, he had trouble with the “made in China” throttle bodies. I’m sure there’s lots of info if you Google it. Probably not much on 351C systems specifically but the Speedmaster systems in general. Other than the throttle bodies, my concern would be the ECU. I don’t believe any self tuning ECU can be expected to work on an IR intake. It may make the engine run but that’s about it. 72panterasteve has an IR intake and one of these Fast ECU’s. He eventually wound up taking the car to Blaine Carmena to have the system tuned. 

I would have cautions about it also. It's one of those items I suspect that you can't know the issues until you have one but I don't think that is going to be unique to anything available?

I remember considering what is now the Borla IDA lookalikes. I got a PM from someone in the UK who said he was a distributor of them and to avoid them.

What he said was pretty much the same thing. You couldn't idle the engine down because the idle screws would stop responding. He thought that was because of the lack of tolerances in the throttle bodies themselves.

I don't know how accurate that is since I stayed away.

I do know that the IDA's in a sense are like that. They stop responding at a certain level. It really is not a lack of close enough tolerances in that case, it's just the limit of the design of the carb and the effect the IR manifold has on them.

Remember those were adapted to American v8's on IR manifolds. Not completely designed from inception for them?

 I've never used any of the aftermarket CPU's so I'd have to rely on good advise from previous experiences of similar applications. School of hard knocks teaches you quickly and hopefully you don't repeat the same mistakes again and again?

 I'm not necessarily defending or condemning anything made in China. No matter where it is made, you get what you pay for and certainly the Chinese are quite capable of building high quality and high precision pieces. They are also quite adapt at borrowing others technology. I suppose if you borrow something and never pay for it, that is one definition of stealing?

As I mentioned, the Borla's supposedly were having tolerance issues and they were being machined here in the US.

 I'd like to actually see the Speedmaster manifolds in person. Looking at those slots they are using for mounting to the heads raises some questions to me?

Nice engine David. How many cubes is it?