I was wondering if anyone has seen this intake before? here are three pictures. Thanks for any help.

 

no ..but i think i want it

 

It looks like a modified "first" system. There's lots of info on that intake, just do a search.

 

pic

 

No, I take that back, maybe it's just a modified TPI plenum. Not sure what kind of runners those are.

The first system has plate on the front driver side so you can side mount the TB if necessary, that pic doesn't seem to have one.

 

here are some more pictures, yeah, it looks like stock but it's different

 

last one

 

Yep, looks like a modified factory plenum. Here is another one that's been modified. Hehehe.

 

what about the runners?

 

The runners are modified SLP. Here is a picture. This modification picked up 21RWHP and 23RWTQ. Peak horsepower is now at 5000rpm and peak torque is at 4600RPM.

 

That looks good, nice job on those.

 

I don't know what it is but i'm going to say that it isn't modified OEM

 

Well, its certainly not factory by any means that I can see, the runners and intake base for sure.

The runners are more oval than round. Plenum looks like possibly some type of aftermarket, cant really tell with out more pics of it.

Have any type of emblem or labels on it? I see casting numbers on the plenum, that may shed some lite there. Also looks like some numbers/letters on the base. throw those out too.

Lots of folks have made TPI parts over the years and quite a few places folded in the 90-95 range as well. changed names, went out of business or quit making stuff period.

Possibly a rare 1 of 100 run that made it to production or something that was being prototyped to the point of production possibly.................................

Give us any details that you can.

later
Jeremy

 

None of those are factory parts.

Very interesting stuff.

 

I am buying it from another person But I will add more updates as they come. Thanks for all the help everyone

 

It's a GM in house prototype from 88 or 89 you can tell from the numbers on the bottom of the plenum or the front of the base. I have a GM LT1 prototype from 1990 with a third gen EGR on it and a hole for the dizzy factory cast on it.
Now the bad news you will find the machine work is not good (not production) and the casting is one off, so port match and wall thickness will be all over the place and little things will be not right or why is this not in the right place. It was a test part thats why.
The bad part about is now you can get aftermarket parts with no fitment problems, be smog legal and go faster.

Jerry

 

A couple more things look at the bottom plenum its for S.D. not a MAF car are you installing it on the 86 in your sig. and if so have you converted it to S.D. Also what type of external EGR are you going to use note no EGR passage on the runners.

Jerry

 

I did not know that it would not work for MAF, it would be for my 87 iroc. I am also not using the egr.

 

If your not using the egr then thats not a problem. The intake can be used with a maf, just not one with the 9th cold start injector, Sorry about the bad info. Do you have the 9th injector now.

Jerry

 

My car has the 9th injector now. So you think I would be better off looking for aftermarket than using this intake?

 

Run an 89 chip and you can ditch the 9th injector.

 

That modification alone picked up that much power? With the addition of a siamesed base and that crazy plenum with 1 gigantic hole on each side, won't that starve a cylinder or 2?

I'm not being a smartass, I'm just totally confused with things I can do to the TPI to flow better. Some say porting does nothing and you will only gain a tenth if I'm lucky. However, 21whp and equal torque should help out quite a bit. More than a tenth anyway.

 

Those are HEAVILY modified SLP runners. You can't do that with normal porting.

 

Howdy BigWhiteGTP

The post above is correct in that they are "HEAVILY" modified SLP runners. The Edelbrock intake is not siamesed. However it is Extrude Honed to 1.70". Basically the Plenum was made larger and no cylinders will be starved. The runner length is now somewhere between 11 and 12 inches.

My new times are posted below. I estimate the weight of my fully loaded GTA at 3550 pounds plus my weight of 250 pounds. With the addition of a YankSS3600 stall converter to replace my SLP 2400 converter and the TPI modification I picked up .6 of a second in my et. I also picked up 2+MPH.

I figure the TPI mod and the Yank SS3600 both picked up .3 of a second. Allen

 

i heard that doing that will cause distribution problems, cylander going extremely lean and so forth, has anybody else heard of this?

 

I don't see why... all he really did was make the whole intake runner a plenum extension... So instead of having the limited plenum space of a stock TPI unit, there's MUCH more plenum area and the "Intake Runners" are now just what's cast into the baseplate.

In other words, lots of plenum, shorter runners - no reason for air starvation. But on the other hand, one might ask himself - why not just get a superram as this point?

 

Because long tubes are sexy.

 

I'll let maximus de mad take this one.

 

Oh yea, 86z... more pics!! (or pm me)

 

I bought the intake in this thread.

Once I clean it up and have some time to play with it, I will post more pics.

Jerrywho, can u post some pics of your lt1 prototype intake.

anyone who has pics of information on prototype intakes are more than welcome to share if u have something.

We know next to nothing about factory stuff tested on these cars outside of a few shwocase cars built

later
Jeremy

 

I have one for sale on the Corvette Forum C4.....its a Rare factory TPI designed for 5.7 motors not too many around mine came from LPE