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Discussion Starter #1
Starting a second engine build. this one will not be stock. would love hear your opinions on the Edelbrock intake vs the stock Pontiac.
The edelbrock should give top end power but at what cost?
 

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Would not use an original Torker.

A Torker 2 is great on a 455 or larger cube build. The slight loss of low end torque is more than made up for by the torque of the long stroke. The carb flange is for square bore carbs only.

A factory Q-jet intake or a Performer is good on a MILD 400 or smaller cube build.

A factory Q-jet or RPM is good for high performance street builds of 400 cube & larger.

A factory Q-jet is the best all around intake for most any Pontiac street engine build.

As you go up to higher hp and/or big cube builds, then other intakes are better, such as the KRE Northwind & Edelbrock Victor. And, as you get up to near 500 cube & larger builds, many go with a 4500 series Dominator carb.

Bottom line to me is that if you're gonna use a Q-jet carb, a factory Q-jet intake is hard to beat. This has been proven over the years by dyno & drag strip results. There have been lots of Pontiac 400 & 455 powered Stockers that have run 1/4 mile times in the 10 second zone. And some of the 400's will turn 8000 rpm.
 

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Discussion Starter #3
Would not use an original Torker.

A Torker 2 is great on a 455 or larger cube build. The slight loss of low end torque is more than made up for by the torque of the long stroke. The carb flange is for square bore carbs only.

A factory Q-jet intake or a Performer is good on a MILD 400 or smaller cube build.

A factory Q-jet or RPM is good for high performance street builds of 400 cube & larger.

A factory Q-jet is the best all around intake for most any Pontiac street engine build.

As you go up to higher hp and/or big cube builds, then other intakes are better, such as the KRE Northwind & Edelbrock Victor. And, as you get up to near 500 cube & larger builds, many go with a 4500 series Dominator carb.

Bottom line to me is that if you're gonna use a Q-jet carb, a factory Q-jet intake is hard to beat. This has been proven over the years by dyno & drag strip results. There have been lots of Pontiac 400 & 455 powered Stockers that have run 1/4 mile times in the 10 second zone. And some of the 400's will turn 8000 rpm.
Thanks for the input on the intakes. I do like Q-jet carbs is there a particular year that flows better of the Pontiac stock manifolds?
 

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"...is there a particular year that flows better of the Pontiac stock manifolds?"


Although the later intakes LOOK bad, they have been proven to flow almost exactly the same as the earlier year intakes.

For '71 & earlier heads I'd recommend a '68-'71 Q-jet intake. Not a lot of difference.

For '72 & up iron heads I'd recommend a '72 Q-jet intake. They have the small heat crossover hole on the passenger side. They are a 1-year-only design. The '68-'71 intakes have a larger rectangular hole on that side.

Beginning in '73, the iron intakes had a big EGR valve on the pass side of the carb tower, & use a hot air intake choke system, with heat tubes going down into the intake, near the mouth of the exhaust heat crossover. These & the next several Pontiac iron intakes also had huge sumps underneath, which added lots of weight & required a deeper sump in the valley cover.

https://www.pontiacdiy.com/pontiac-v-8-intake-manifold-performance-guide/
 

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Starting a second engine build. this one will not be stock. would love hear your opinions on the Edelbrock intake vs the stock Pontiac.
The edelbrock should give top end power but at what cost?

First you have to define what "will not be stock" means to you - and us. It could be just a bigger cam or a stroker kit, aluminum heads, roller cam, headers, etc..

Aluminum will be lighter and may be of help in keeping fuel cooler.

As bigD points out, the original Torker was really misnamed. It is an open plenum intake with what was known as the "Volu-Step" floor which was a lowered floor area below the primary bores of the Q-jet whose purpose was to minimize the A/F mixture from slamming into the intake floor. It did prove to show power improvements above 5,000 RPM's, but it gave up torque on the lower end which is typically where the street Pontiacs make power.

The Torker II is a redesign said to be improved, but still an open plenum intake and you can't just bolt on a Q-jet as it is made for the square bore carbs like Holley.

From what I read, the Edelbrock Performer and Performer RPM are often the aluminum intakes of choice. Each has its differences, so you want to read up on them at the Edelbrock website if you choose this route.

You also have several "older" intakes that can be had off Ebay for a reasonable price if you want to experiment a little with an aluminum intake. I have/had used an Offenhauser 360 intake on my previous 400CI build. It is an open plenum design and I used a Q-jet. It was a freebie so I tried it. Seemed to work great for me, but this was with a 3-speed manual trans. Perhaps an automatic with stock converter, 3.08's or something in the 2.?? gear ratio range might prove differently.

If you want visual looks, I am a dual quad guy. Nothing like 2 AFB 4Bbls sitting on top of the engine and in my opinion, better fuel distribution when you open them both up.

The tried and true as bigD stated, is the factory cast iron Q-jet manifold and Q-jet. In my opinion, nothing sounds better when those big secondaries pop open and you get that deep tone through the exhaust. I believe it was around 1971 that the Q-jets were 800 CFM's. I would have to check Cliff Ruggle's book.
 

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"...I believe it was around 1971 that the Q-jets were 800 CFM's..."


Just to add some details to this statement.

I think Pontiac did use an 800 cfm Q-jet on a few engines in '71. The increased cfm was achieved by deleting the outer booster rings in the primary throats. These carbs did not prove to be real street friendly, so were discontinued.

The next Pontiac 800 cfm carbs were used on the SD455 engines. They had dual booster rings, but larger diameter throats.

Buick used the big throat 800 cfm carbs on some(maybe all ?) of their 455 engines, in the early '70's.

All Pontiac Q-jets from '76 thru '81 were big throat 800 cfm, with the APT feature. Most other '76-up Q-jets were also 800 cfm.

As Cliff Ruggles has posted, most of the '76-up Q-jets really need lots of work in order to function correctly in high performance apps.

My experience is that many Q-jets from '68 thru the early '70s, didn't require a lot of extra work, in order to work great for hp street or even drag racing. Fewer emissions related restrictions, as produced.

Edelbrock also sold some Q-jets, in the '90's up thru the early 2000's. Some had the 750 size throats & some had the 800 size throats. But they rated most of their big throat carbs at 795 cfm. I have one of these, a 1904, on my 455 bracket engine, on a Chinese single plane intake.

The Chinese single plane intakes appear to be copied after the Holly Street Dominator intake. But, they do not have the exhaust heat crossover.
 

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Discussion Starter #7
First you have to define what "will not be stock" means to you - and us. It could be just a bigger cam or a stroker kit, aluminum heads, roller cam, headers, etc..

Aluminum will be lighter and may be of help in keeping fuel cooler.

As bigD points out, the original Torker was really misnamed. It is an open plenum intake with what was known as the "Volu-Step" floor which was a lowered floor area below the primary bores of the Q-jet whose purpose was to minimize the A/F mixture from slamming into the intake floor. It did prove to show power improvements above 5,000 RPM's, but it gave up torque on the lower end which is typically where the street Pontiacs make power.

The Torker II is a redesign said to be improved, but still an open plenum intake and you can't just bolt on a Q-jet as it is made for the square bore carbs like Holley.

From what I read, the Edelbrock Performer and Performer RPM are often the aluminum intakes of choice. Each has its differences, so you want to read up on them at the Edelbrock website if you choose this route.

You also have several "older" intakes that can be had off Ebay for a reasonable price if you want to experiment a little with an aluminum intake. I have/had used an Offenhauser 360 intake on my previous 400CI build. It is an open plenum design and I used a Q-jet. It was a freebie so I tried it. Seemed to work great for me, but this was with a 3-speed manual trans. Perhaps an automatic with stock converter, 3.08's or something in the 2.?? gear ratio range might prove differently.

If you want visual looks, I am a dual quad guy. Nothing like 2 AFB 4Bbls sitting on top of the engine and in my opinion, better fuel distribution when you open them both up.

The tried and true as bigD stated, is the factory cast iron Q-jet manifold and Q-jet. In my opinion, nothing sounds better when those big secondaries pop open and you get that deep tone through the exhaust. I believe it was around 1971 that the Q-jets were 800 CFM's. I would have to check Cliff Ruggle's book.
The reason I asked this question is I was looking into going with aluminium Heads and intake to reduce heat soakage and keeping high compression . This is a for "fun" build so am not married to keeping it original. With the info you and others has generously given it looks like I will stick with the cast Pontiac Intake and heads. The negatives and price of the heads have added up to the point that for myself it doesn't make sense as this will be a street car. Thank you and Big D for the knowledge about Intakes. sometimes it's better to keep it simple.
 

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Agree that the stock Q-jet intake is the ticket. If you want aluminum, Pontiac made those too. Be prepared to pay $$$ for one, though. They look and perform great. They also have a divorced water passage so you can pull the intake without draining the coolant.
 

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The reason I asked this question is I was looking into going with aluminium Heads and intake to reduce heat soakage and keeping high compression . This is a for "fun" build so am not married to keeping it original. With the info you and others has generously given it looks like I will stick with the cast Pontiac Intake and heads. The negatives and price of the heads have added up to the point that for myself it doesn't make sense as this will be a street car. Thank you and Big D for the knowledge about Intakes. sometimes it's better to keep it simple.


The price of aluminum heads, roller cams & lifters, roller rockers, etc. really adds up fast. Sure, you can pull some big HP/Torque numbers out of these goodies over the stock stuff, but I just can't justify it for a street car IF you want to drive it more than around the block or to your closest McDonald's to hang out and look cool.

If you don't plan on driving the car in the cold or winter months, which most do not, then start with blocking off the exhaust heat crossover passage to keep the factory intake cooler. You can try a set of intake gaskets that are designed to do this OR you fill in the passage with furnace cement. KRE Pontiac has an intake gasket set for the RAIV without the exhaust block-off plate, BUT, look at the bottom of the page and they sell it separately. Kauffman Racing Equipment

There are other gasket options as well from Felpro and Mr Gasket that offer the blocked off passage plate. Some here simply cut a piece of thin stainless steel to do the job.
 

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"... If you want aluminum, Pontiac made those too...They...have a divorced water passage so you can pull the intake without draining the coolant..."


Not to argue, but just to keep the facts straight, the Pontiac alum intakes for the RA4 & 455HO engines had divorced exhaust heat crossovers. The water crossover was cast as part of the intake. They can obviously be cut & separated if you wish.

Reproductions are now sold. BUT, these have gotten lots of bad reviews, for having badly mis-matched ports. At one time, The Parts Place advertised a ported version. I assume that these would be gasket matched. I'd say that these are not worth the price, over other available intakes.

Here's a Chinese single plane similar to the one I have.

https://www.ebay.com/p/Speedmaster-Pce147-1060-Shootout-Series-Intake-Manifold/1042680996?iid=352560337330&chn=ps

You can get one cheaper if you don't mind having to plug up the injection holes over the ports.

https://www.ebay.com/itm/Speedmaster-Intake-Manifold-PCE148-1038-Shootout-Multi-Port-Satin-for-Pontiac/264118195282?epid=2143806359&hash=item3d7eabd452:g:nqYAAOSwxFVcL34d
 

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heres the Offy 360 with dual Demon carbs, the demons bowls are similar to the old quadrajets (small front, large rear) and much easier to service. I still get good mileage with sequential throttle bar, since at easy acceleration its only on the first primary, starting to dip into the rear. then at open throttle you can feel secondaries come in between shifts.
 

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Discussion Starter #12
heres the Offy 360 with dual Demon carbs, the demons bowls are similar to the old quadrajets (small front, large rear) and much easier to service. I still get good mileage with sequential throttle bar, since at easy acceleration its only on the first primary, starting to dip into the rear. then at open throttle you can feel secondaries come in between shifts.
Very nice engine, it must be a blast to drive. nay problem with hood clearance?
 

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yeah like driving a 462-480 hp sewing machine...i thought the duals would be a pain on the street but i love it. and theres never a lack of more pedal, still pulling hard at 80-90. only had to add 1" spacers to make the RA intake fit the hood, good clearance with the GTO hood.
 

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I've had two different Edelbrock intakes on my car. The first was a Victor paired with a 750 Dominator and if you look at the first couple posts on my thread on my restoration (https://www.gtoforum.com/f83/68-gto-resto-mad-max-meets-pro-tour-130082/) you will see what I had to do for clearance for that intake. The Carb/Cam/Intake combination there was not street friendly at all. She wanted WOT or nothing at all.

https://flic.kr/p/24ieQdY

Now I'm running Edelbrock Performer RPM intake and have the matching Performer RPM heads. I did a gasket match to the intake and needed to use a drop base K&N filter which gives me about 3/4" clearance to the hood.
[/url]Untitled by paradox_69_666, on Flickr[/IMG]

[/url]Untitled by paradox_69_666, on Flickr[/IMG]

It's extremely responsive with my Quick Fuel 750CFM carb. I agree though that you can get an awful lot out of a properly tuned QJ, it's just not the rout I went with.
 

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I went with Edelbrock aluminum heads, Edelbrock intake, roller cam and a 750 Holley. I'm just restoring as a street car, but wanted some extra power. I was first planning to use the original heads, but the lead time to get them ported by Butler was pretty far out, and they told me the Edelbrocks would flow as well or better, and would be about the same cost. I had the cam ground per their specs and the engine puts out close to 450 hp on the Dyno at Butler. After three years of work, the car is almost ready. Just final assembly touches needed.
 

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I went with Edelbrock aluminum heads, Edelbrock intake, roller cam and a 750 Holley. I'm just restoring as a street car, but wanted some extra power. I was first planning to use the original heads, but the lead time to get them ported by Butler was pretty far out, and they told me the Edelbrocks would flow as well or better, and would be about the same cost. I had the cam ground per their specs and the engine puts out close to 450 hp on the Dyno at Butler. After three years of work, the car is almost ready. Just final assembly touches needed.
Sounds like you're close to finishing.post some pics if you get a chance would love to see it.
 

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I'm very close, all body work and paint is done. Just ordered the last (I hope) few pieces to complete the build. All that is left is to replace the glass, front and rear bumpers and weatherstripping on the side windows and install a new steering wheel. We had a few holdups that seriously delayed the build. Last year, when we were getting ready to put it back together, we found that the harmonic balancer had shattered inside the timing cover. Removed the engine, shipped it back to Tennessee for tear down and rebuild. That took several months. I hope to be driving it soon. Will post pictures once I meet the ten post requirements.
 

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Discussion Starter #18
Good luck with the rest of the build. Waiting to get my engine back, 400 bored out 0.040, stroked4.25, 16 heads, 068 cam, -22cc dished pistons. It should spin the tires.
 
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