i'm building my first motor for my 1992 trans am tpi, and this is my first time ever messing with fuel injection and everyone is telling me to upgrade to the weiland vortec stealthram instead of buying the sdpc vortec tpi manifold. i've heard a couple different arguments about whether or not the intake fits under the hood of the trans am, does it? and what modifications will i need to make to the hood to fit the intake under the hood? and also what will i need to buy to make this intake work in my car? some one told me new fuel rails is this true? what else will i need? will this intake work with my stock computer and wiring harness? and can i use a tpi throttle body or will i have to buy a lt1 throttle body. like i said this is my first motor and first fuel injection so any help is greatly appreciated. here is the link: http://store.summitracing.com/partde...5&autoview=sku

 

I would sugest doing a search and checking out stealthram.com

but to answer a few of your questions Yes it will fit under the hood the braceing over the throttle body needs to be removed however

you will need new fuel rails holley makes specific ones for the manifold

you will need vortec heads to work with a vortec manifold if your keeping you stock heads you will need a standard stealthram and some offset ground washers

it will work with your stock computer wiring harness and sensors but you will need a few plugs and things of that nature for the intake

It will not work with your stock water neck you will need a standard late chevy thermostat housing when you change over

it will work with all your factory bracketry and throttle body

you will also need to make new fuel lines I used adapter fittings and -6 AN line from aeroquip to do mine but there are many other ways

any other questions?

 

Are you planing on buying the vortec heads for this build up? You know there is a difference between them and regular SBC heads right?

 

i know the weiand intake manifold is vortec.

 

Maybe one or 2 of them; but Weiand has been making manifolds for about 4 decades longer than Vortec heads have been around, which includes about 3 decades before Holley bought them out, and for 4 decades and a couple of years before the Holley Stealth Ram got offered with the Vortec port location.

"Vortec" is a GM marketing word that when translated into normal English, means "we moved the intake ports up toward the valve cover about ¼ inch". The advantage of this is that it allows the port to be much straighter, i.e. much less of an "angle" where it makes the turn to meet the valve, than earlier heads. The ports are moved SO MUCH that most older intakes won't even completely cover the head ports.

If you're buying heads with the Vortec port location, then you'll have to buy a corresponding intake. If your heads DON'T have the Vortec ports, then you CAN'T use a Vortec-port intake.

So before you bite off on the whole "Vortec" buzzword, determine what heads you're running.

What heads are you running?

Apart from that, the HSR has issues fitting under a Firebird hood; but most people report that they can hack out a certain part of the hood bracing and make it clear. At least, while the engine and car are totally at rest.

Yes you will need the HSR's fuel rails, they are different from the stock ones. Which TB to use depends on which cables and brackets you're using; some cars, the LT1 TB fits much better than the original. Yes you can run a stock computer and wiring harness, since none of that cares what shape the lump of aluminum is cast into, except that a couple of wires may need to be a tad longer (but maybe not). Yes you may need to re-program the ECM, depending on what cam you use; and you may need different injectors, since however much extra air you can get into the motor, also needs extra fuel.

First order of business though, is to separate the "Vortec" buzzword fantasy from your personal reality.

What heads will you be running?

 

just like i said i will be running the VORTEC heads i ran the numbers and they are VORTEC heads from a truck. the whole motor is from a 96 tahoe it is a 350 VORTEC. I've allready found out what i'm working with i just wanted to know about the hsr. thanks for the information that has been given.

 

I would look into getting new valve srpings installed on theheads. I dont think the stock ones canhandle anything over .480 lift but dont quote me on that. I dont think you said weasther you were using a 350 or 305 for this buil. what engine are you using

 

Maybe I missed something somewhere? Maybe we all did?

However all that may be, none of your questions really is particularly dependent on whether the heads have the raised intake runners or not. The main thing of course, is to make sure that you get the Vortec version of the HSR if you're running Vortec heads, and the regular one if you're not. I think most of the other questions have already been answered.

The question as to what size engine this is, was a good one too; I seem to have overlooked that part of your post as well.... not that it matters to how it all fits, since all SBCs are the same dimensions externally. But you can help everybody get right straight to the point if you start out your post with something useful. For example instead ofyou could try something more like "I'm building a 350 with Vortec heads off of a 96 truck for my 92 Trans AM", and then we'd all know that much better what you're working with. We are all just super PITIFUL mind readers around here.

I think the advice to use the HSR instead of the SDPC TPI base is excellent. The only downside is, the HSR is NOT emissions legal, strictly speaking; it has no provision whatsoever for EGR, which if you live in a place with strict visual inspections such as California and some other places, will render your car unable to be licensed. I don't know the rules in your locality; I can't read their minds either. That's something you'll have to be responsible for yourself. There are few things worse than spending a big pile of money on a motor, and then discovering that it's inherently illegal in your particular locale; if that happens, then there's not much that any of us here can do to overcome that for you, short of telling you to take it all back apart and put the stock stuff back on it. Not alot of fun.

To get the full benefit of the HSR, you need to run ALOT more cam than a stock one. That means, ALOT more lift, and ALOT better valve springs will be required. But Vortec heads are notorious for their huge gob of metal they call a valve guide, that's so big in diameter that normal valve springs won't go around it, and so tall that the retainers smash into it at about .480" of lift more or less. Definitely plan on getting those cut down at the same time that you get all your other head work done. Also, definitely plan on running a roller cam, if at all possible.

IIRC the LT1 TB has its throttle cable attachment in a place and direction and all, that works MUCH better with the way that the brackets on the HSR fit. I don't recall the details.