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Hello again. I am looking to take my 1970 Esprit to the next level. Currently it is all bone stock.

I am looking to get some additional power on this car without turning it into something else. Just for street use.

Right now I'm looking into intake manifold and carburetor. I was told Edelbrock was the way to go, but that was several years ago.

I'm wondering what others with the 350 engine have done in terms of intake manifold and carb, for just street use

Thanks
 

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is your 350 currently a 2 barrel? The factory 4 barrel manifold is the best choice for most of these engines. I am running one on my 455 with over 500 H.P. If you look around you can pick one up for 50-75 dollars If you really want aluminum then the Edelbrock performer would be ok for the 350, it chokes off the larger ci motors at rpm. Do not use the Performer RPM as it is much taller and well not clear the hood on a 2nd gen bird without a lot of modifications. as far as Carbs go the Quadra Jet is a great performance carb that well also get good fuel economy. Most here will recommend it. Stay away from the E carbs they have a lot of issues some can make them work but be careful. If you can not find any one that will set up a Q-jet for you a Holley will work fine but you will need to go to the performer manifold as it will accept both square and spread bore carbs.
 

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'70 Esprit TA clone Pontiac 400
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I agree with David, factory manifold with Quadrajet or Performer with 575 - 600 Holley, Demon, or QFT carb. I got the Performer with 575 Speed Demon then swapped engines to a 400. Be careful not to over carb if you go with the aftermarket one's. Putting a 750+ CFM Holley etc. on your stock 350 won't work as nicely as a smaller unit. I don't really like the E carbs so I left them out.
 

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I agree with most others that an iron intake and a GOOD Q-jet is hard to beat.

Any '68-'72 iron Q-jet intake will do. And most any '68-'79 Q-jet will do, except the '75 models. These had an extra jet and metering rod. These did not work out very good, therefore were dropped, and are not desirable. :no

Since you have a manual trans, most any throttle lever type can be made to work. If you plan to change over to a TH350, you'll need a Q-jet which has the lever which has a provision for the TH350 kickdown cable.

Another consideration is the Q-jet type. The Pontiac Q's from '71-'79 have a big "smokestack" vent on top.which requires a hole for it, in the air cleaner base. If you don't want the big vent, you can use a '68-'70, non-California Pontiac Q, or a Buick or Olds Q. If you don't mind running a side inlet model you can even run a Chevy or Edelbrock Q. The Edel Q's are actually the newest. I think they were still made in the 90's and maybe into the early 2000's--not positive.

If you'd rather run an alum intake, for looks and/or weight savings, the Performer will work just fine on a 350. The price of new ones has gone up to near $300. But there are usually some used ones available for half that. :yes
 

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70-f400 - I am not sure if my existing carb is 2 or 4 barrel. I only know that it's been worked on before by a carburetor shop. Most of the repair history files on this car were lost at my mother's home at some point. But it was my mom's car and she bought it from the factory. She said she had the carburetor worked on. I would really like to buy new parts. I have five older cars and I am at the point where if it's not a 'no longer manufactured part' which is not available new, or something that I'm forced to have a machine shop make for me at high cost, then I will buy it new in order to minimize problems. That being said I sell used car parts online as a part time job, so no offense intended (I need people to buy used parts from me, otherwise I go broke LOL). But you know what an intake manifold is a solid peice of metal, and unless it's been worked over by a machine shop than a piece of metal's a piece of metal, right? But on the other hand, why take a part which is stock and ruin it, when I know for a fact it was original to my car. Plus machining intakes and cylinder heads is a black art, with no real provable results unless you hook up your intake to a machine before and after and have it flow and pressure tested, which is something I prolly can't afford.

I did read an article from high performance pontiac magazine which discusses later model mid-70's aftermarket versus stock intake manifolds though, and it talked about how people weren't getting much better airflow from aftermarket intakes, even though the stock one looked like it left much to be desired. I didn't know if the same applied to 1970 models or not, because I'm not knowledgeable yet about the generations of Pontiac, and what parts are inter-compatible by chassis and/or generation.

After reading your post and doing a search, I see that Quadra-Jet refers to Rochester brand. I have only heard of Edelbrock and Holley and Weber, however even though I haven't heard of Rochester company, I have heard the name Quadra-Jet or Q-Jet being thrown around before. So is that a well-known aftermarket carburetor for the 1970 firebird that would be equal in quality to, say an American or Euro made Weber or and Edelbrock? Years ago I used to have an Edelbrock magazine with a lot of parts for my car, back when I had no money and big dreams. And there were a lot of parts listed for my 1970 firebird. But now the Edelbrock website barely lists things as compatible with specific years.

By E-carb, do you mean one that has smog control parts on it? Because in California, cars before 1976 don't require smog parts on them, or even a smog check or test. So I will definitely be avoiding those parts. I secretly remove EGR components from my Mercedes cars, and I also replaced my exhaust pipes on one of them, which had a catalytic converter, with a 'Euro model' downpipes which had the 'pre-cats' on them. I had a muffler shop chop off the pipe right before the pre-cats, and gut out the honeycombs inside, and then re-weld it back together, and then I had the downpipes coated down to a certain point (very expensive process) with a special ceramic coating, so that the smog shop can't even tell the difference. Anyways these days I pay a smog guy to do my smog, ever since the requirements went up a couple years ago, so it's no longer relevant.

NOT A TA - from your user name and pictures, I can tell your 1970 firebird was an Esprit or 400, and now you are putting on the TA spoilers and making something awesome of your car. Good for you, man. That was my dream back in the day when I had no cash and a 'Year One' magazine. I selected all my parts that they sold in the magazine to convert my Firebird regular orbit orange car into a trans am. But then my mom looked at the the list and the price and laughed at me. She said I'm lucky she's paying my insurance and half the price of gas. Nowadays I have some more cash, so you never know I might have my car on jack stands for a while and see what I can do.

OK, thank you for the advice. It sounds like Rochester Quadrajet or Edelbrock Performer (but not Performer 'RPM') is the way to go. I didn't find the 575 Speed Demon on the Edelbrock website, but I will look into it. And I will definitely avoid a large flow carb such as a 750+ CFM. Thank you

ponyakr - Does my car from the factory have an iron intake manifold? That seems much heavier in weight than the aluminum of the Edelbrock. But if there's no noticeable difference in airflow, why even bother, right? Other than maybe you want to replace the intake manifold gaskets and refresh the mounting bolts, so you might as well swap the manifold at the same time, right? Who knows maybe I should buy the Edelbrock, do the aforementioned, and take my stock intake to a machine shop and have them work their magic on it. Maybe they can make it flow better than an aftermarket intake.

Also noticed I was mistaken to put manual transmission. The car has an automatic transmission unfortunately. So I will now know if I buy a Q-jet, to buy the additional bracket for the kickdown cable (I believe the Edelbrock version of this cable is part #8015 (http://www.jegs.com/i/Edelbrock/350/8015/10002/-1). Is that what you're referring to?

Yeah when I saw the black coated Edelbrock intake, I thought that was the bee's knees. But I'm not married to any one brand. I just have this sense that the intake and carb should be of the same company if at all possible.
 

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Your Esprit most likely has a 2 Venturi carb on it. If you take off the air cleaner top and take a pic we can easily tell you. If you have a 2 V you can't use the stock intake manifold for a 4 V.

Notes:

Quadrajet carbs were the factory installed 4 V carbs made by Rochester who also made the 2 V carbs used by the factory.

Speed Demon is a model of carb made by Barry Grant.

Machine shop can't work any magic to modify a stock 2 V cast iron intake to properly accept a 4V carb unless you bring a wheel barrel full of cash.

It's more common then not to have intake and carb produced by different companies. Even stock they weren't made by the same company.
 

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I agree with the other guys and thats what I do.

Thats the best way to minimize problems.

I use also stock parts.

He next step is also to change my carb and intake to a 4bbl.

The only problem is the side fuel inlet, the 2bbl have a strait one.

But the 350cui engine have more power I think.

The other problem is, where to get. In germany nothing to find, very rare.

So I have to order in the US and have to pay the high shipping costs and tax here.

But, I HAVE FUN!!!!!!!!!

Regards
Sascha
 

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"...Quadrajet carbs were the factory installed 4 V carbs made by Rochester who also made the 2 V carbs used by the factory..."

Q-jets were also made by Carter, and later by Edelbrock. So, you can now buy Rochester, Carter, or Edelbrock Q-jets. All the E-Q's had side inlets. Carter and Rochester Q's come in both front and side inlets. There is no performance advantage to a front inlet. But, a side inlet will require a little more plumbing, on a Pontiac engine, since the fuel pump is on the driver side. :yes

http://www.carburetion.com/Rochester.asp
 

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"...Quadrajet carbs were the factory installed 4 V carbs made by Rochester who also made the 2 V carbs used by the factory..."

Q-jets were also made by Carter, and later by Edelbrock. So, you can now buy Rochester, Carter, or Edelbrock Q-jets. All the E-Q's had side inlets. Carter and Rochester Q's come in both front and side inlets. There is no performance advantage to a front inlet. But, a side inlet will require a little more plumbing, on a Pontiac engine, since the fuel pump is on the driver side. :yes

http://www.carburetion.com/Rochester.asp

Good catch Don, glad you're here to keep me in line! I should have said the '70 birds that had 4V carbs were Quadrajets made by Rochester AFIK. I forgot about the others, probably cause I never dealt with any other than the Rochesters.
 
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