[Ozz1967]

I've got a few questions about buying the right intake manifold and carb...

For those that have been following my myriad of posts, I'm building a 350 with Vortec heads. I've settled on the Cam, pistons etc however i'm having difficulty with the manifold and carb selection. Both Edelbrock and Weiand make an intake for the Vortecs however Edelbrocks is a "highrise" type.

1. Will a highrise intake fit under my Trans Am Hood?

2. From what I've been reading, getting a Q-Jet carb is the best option however, the only ones I can find are remanufactured. Are there any "new" Q-jets out there? Also, none of the vortec intakes support the exaust heated chokes...how hard is it to install an electric choke?

3. How big of a carb should I get? I'm thinking in the 650 range as I've heard its better to err on the small side than to over-carburate the motor. Then, dual or vacuume secondaries? This would all be moot as I hope to go with a EFI in the future, i just don't have the cash to do it now. It's an extra $1400 minimum if I go that route...unless someone knows where I can get a used set up somewhere.

4. I want to keep it emmissions legal. Being in the military, if I get say, stationed in California (and some other states), they are going to have a complete fit if I try to get my car registered there and don't have the right emissions gear on it. Any suggestions for that or am I just dreaming about keeping some sort of emmissions on the car? (smog pump, egr)

5. How would I put an egr set up on a car with an intake manifold that doesn't have that capability? Is it even possible?


Ok, I know that's a lot of questions, and I really do appreciate any answers you guys might have for me. Thanks!

[copndoc3]

Hi Ozzie, sounds like your building a good all-around have fun vehicle. I also built a 350 Vortec to use in my 51 Willys. In answer to your questions, I used an Edlebrock performer manifold on mine and it seems to be working out OK. As I'm sure you know, Edelbrock makes the Performer, Performer RPM, and the Air-Gap Performer RPM for the Vortec engine. I'm reasonably sure that the Performer is the shortest of the three and would fit under the hood of your TransAm. The old saying is anything will fit under the hood......the question is if the hood will close with the manifold you choose. If memory serves me right, I believe there are height specs in the Edelbrock catalog. Might want to investigate there. As for a carb, your right to err on the smaller side since most of your RPM will probably be under 4000 RPM. Edelbrock makes two carbs which would suit you. Either the Performer Series or the Thunder Series. Both are based on the old AFB theory, but have been revamped by Edelbrock. I'm guessing your in 20's and don't remember too many cars of the 50's. The AFB (Aluminum Four Barrel) was used on Chryslers and some others back then and was a good carb. It has the advantage of being able to change the jets without flooding the manifold with raw gasoline. But I'm sure their are as many pro's and con's to the Edelbrock carbs as there are to Holley. The Performer is available in a 600 and 750 CFM models and the Thunder series is available in 650 CFM. Anything more than that would be a waste of money on the street. EFI is nice, but like you say, pricey. If you want to keep it emissions legal, than the basic rule is: if it came from the factory with it on, it needs to be on. That includes air pumps, catalytic converters, all vacuum accessories that effect emissions, etc. Most of the states, especially CALIF is really sticky about modifying and "altering" emissions. One way of getting around this is having the vehicle registered in your home state, if your home state isn't one of the sticky emissions states. As long as your on active duty in the military, most states have an agreement with other states that an active duty military member does not have to have an instate registration. Check with whatever state your being assigned to. Lastly, unless the manifold is setup for EGR you wouldn't be able to put one on. Like I said earlier, if came from the factory with one, it has to have one, same place, same function. A correctly functioning EGR valve doesn't alter performance enough for you to notice in the seat of your pants anyway. Good luck Ozzie. We appreciate the great job you and your fellow military men and women are doing to preserve freedom all over the world. Be safe!

[curtis73]

Originally Posted by Ozz1967

2. From what I've been reading, getting a Q-Jet carb is the best option however, that's a "spread bore" carb if I'm not mistaken and none of the vortec intakes support spread bore. They only support "square bore".

Edelbrock makes several; performer, RPM, Air Gap, all for Qjet. Unfortunately, none come with EGR provisions. There are carb squarebore options that are smog legal, but I agree with you; Qjets are incredible street/performance carbs.

3. How big of a carb should I get? I'm thinking in the 650 range as I've heard its better to err on the small side than to over-carburate the motor.

If you get a Qjet, you only have two choices; 750 or 800, but no worries. They are designed with air dams that only open as far as the engine needs. GM used these "monster" 750 carbs as late as 1989 on engines as small as 307 cubic inches and as little as 140 hp, so they're just fine as an on-demand flow carb. You're also going to be restricted to an electrically controlled Qjet for emissions reasons which is a tough piece for performance. The electrical part of the carb sets idle mixture and it is very sensitive to performance parts like cams. It will never run right with all the aftermarket stuff you're planning.

4. I want to keep it emmissions legal. Being in the military, if I get say, stationed in California (and some other states), they are going to have a complete fit if I try to get my car registered there and don't have the right emissions gear on it. Any suggestions for that or am I just dreaming about keeping some sort of emmissions on the car?

Its a toss-up here. If you are actually going to have it registered everywhere you go, absolutely you MUST keep everything about the factory emissions equipment 100% intact. You must keep EGR, smog pump, catalytic converter, computer controlled carb, everything. Don't worry; properly operating smog equipment won't take any HP. In reality, they always sap a couple here and there, but don't worry about it. There are tons of aftermarket parts, like the Edelbrock Performer intake that are completely smog-legal, will fit under your hood, and run like crazy. CA is a complete nazi state when it comes to emissions. I failed because my gas cap failed the pressure test by 0.1 psi.

On the other hand, if you're going to keep your registration from your home state while you travel with the military, just follow the emissions laws of your state. Its not legal to do in most states since you have to register a car X number of days after you move there, but many people get away with it. This also affects my reply to your exhaust thread; if you're planning on registering the car potentially in any of the 50 states, make sure you headers, exhaust, and all speed parts are either stock replacement (like the heads and catalytic converters) or carry a CARB EO number (like the intake, ignition, etc.). Cams will either be stock replacement (which are legal) or performance (which are not legal). Since the cam is internal, they can't fail you just for having a non-exempt cam in your engine, but it doesn't take long for the tailpipe sniffer to fail you with a hot cam.

5. How would I put an egr set up on a car with an intake manifold that doesn't have that capability? Is it even possible?

Possible, yes. But not legally for the smog police. The intake has to have the EGR provision. Edelbrock's intakes that are EGR capable have a CARB EO number, but no amount of adding an EGR will make it smog legal.

There are three levels of smog legality; 1) stock replacement part. This covers things like a Comp Cam that is a copy of a factory GM cam, a Fram air filter designed for directly replace your original, or a Holley fuel pump that delivers the stock flow and pressure. These are parts that are designed by the aftermarket for stock performance and emissions. 2) Smog exempt. These carry the CARB EO number. They are performance parts that have been tested and shown to not increase emissions, so they are legal. That is not to imply that you will always pass emissions with those parts since you can still fail the sniffer test, but you won't fail a visual by having those parts. 3) Off road, or for non-pollution controlled vehicles. These are the performance parts like the tunnel ram intakes, huge race heads, or monster cams.

The bottom line is the Federal Government doesn't even allow you to put ANY aftermarket performance part on your car. It has to stay in stock configuration and the only parts you are allowed to put on it are the stock replacements from the first category above, but the only Federal Agencies who could cite you for a violation are the FBI or a Federal Marshall, chances are you won't get busted for a Flowmaster muffler by Special Agent Fox Mulder.

[curtis73]

I just thought of something else... if you go EFI, you could do one of the Edelbrock smog legal EFI conversions. Then you could eliminate the problem of tuning idle on that electronic Qjet.

Another option is to use a GM factory EFI setup from a year later than your car. California allows engine swaps as long as the engine was available in the car (and since a 350 is externally identical to a 305, no one will know) and its from the same or newer year. You could swap a later engine management system, like off of another GM passenger car from your year or later; TBI, Vortec, etc. They won't check the year of the block, so you can just tell them that the engine is a 305 from a 92 Caprice.

If you want to register it in CA, make sure ALL of the emissions equipment; EGR, evap canister, smog pump, everything gets transplanted from the donor car. Then you have it taken to a referee station to be certified as a legal swap. From then on, the smog test goes like this; you visit the smog station and they look at the TBI and **** their head sideways with confusion. You point out the recertification sticker on the door jamb from the referee station. Then they open up their smog manual to check for the laws about engine swaps since they've probably never seen a referee plaque before. Its a headache, but do-able.

[Hippie]

GM Performance Parts has a dual plane intake for the Vortec heads that is nearly identical to the Performer and it is available with EGR, both manifolds will accept either a spreadbore or squarebore carb. Be advised the GMPP piece is considerably more expensive. Edelbrock used to make a carb spacer for squarebore carbs with the pad for EGR so you could retrofit EGR to an older intake, they may still have it available and if they might have one for the spreadbore.

There are currently 2 intake bases I am aware of for installing TPI on Vortec heads, one from Edelbrock and the other from Scoggins-Dickey and both are right at the $400 mark and you would still need the rest of the injection system. The only TBI setup I know of is the factory piece.

[bajaguy]

Jet performance makes high performance remanufactured Q-jets that you will be able to use and hook up all of your factory emissions equipment. I think Edelbrock does the same. Jegs or Summit should have these carbs.

[Ozz1967]

Well, I just got back to the US from Germany and I'm wanting to spend some of my hard earned money to make this thing fast...too bad we don't have any autobahns here...these Wide open and FLAT roads in New Mexico are completely wasted on 60mph speed limits.

I will look into the GM performance parts and see if thats a viable option. The car is currently registered in Minnesota which has next to nothing for emmissions testing. "Does the car run"..."yes".. ok good, it passes.

One thing I didn't think of, but no..I can't. the Q-Jet currently on the car has a heat activated choke...which none of the manifolds have the option for. Bummer.

Anyway, thanks guys, I really do appreciate all this. Oh and Copandoc...yeah, this is going to be one fun ride when it's done. If you guys click on my gallary you will see the TA i'm working on.

[Hippie]

Originally Posted by Ozz1967

One thing I didn't think of, but no..I can't. the Q-Jet currently on the car has a heat activated choke...which none of the manifolds have the option for. Bummer.

Do you mean it has a round housing on the side of the carb with a tube going to it? If so you can buy electric choke conversions for it that replace the outer plate and tube. The one I bought was about $50 or so, you can probably find them for less.

[curtis73]

Yup. You can even do it yourself with a junkyard choke. It just bolts up to the same spot. I like to solder the old heat tube hole closed to keep the proper temp inside.

[Ozz1967]

I just looked into it and the GM Performance parts intake has provisions for both EGR AND a heat choke if I'm reading it right. The down side is that it's $100 more expensive than the others.