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Discussion Starter #1 (Edited)
Hi guys,
Name's Jarred and I just picked up a 1970 Tempest Custom/LeMans and thought I would join here.

I'm new to ole skewl Pontiac's and have tons of questions that'll need answering in due time.

My car's originally a 6.6 car with a 3-speed auto.
Has a weak 326 in it right now rated at a whopping 250hp.. whoopie! Lol.

In the process of getting a 400 from a 78 T/a with the 2.11 valve heads. I cant seem to find the details about the heads though, casting number is 9791214 54?

So far this purticular engine I'm looking at is hard to get details on.
What do you guys recommend as far as getting around 400+ hp out of a 200hp rated t/a motor/heads?


Here's my car:




Need's a mild restore but its relatively clean despite never being restored.
Traded it for a 96 v6 firebird.

Also, checked the VIN and it seems its called a "Tempest Custom" But I cant seem to figure out what badges they had in '70? It's missing a bunch of badges but I have no clue which.

Thanks in advance, looking forward to building this car. :cheers
 

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Discussion Starter #4
That's a really sharp car, I like the Lemans 6.6 stripes.
Thanks. I probably wont be keeping them though, car needs a paintjob and I hate the color. Definatly not a pontiac color. Lol.

Probably going black or potentially the original blue(color of the seatbelts)
Welcome to the club.

Nice car.
Thanks alot. :)
 

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So far this purticular engine I'm looking at is hard to get details on.
What do you guys recommend as far as getting around 400+ hp out of a 200hp rated t/a motor/heads?
Howdy Hot Rod, we're neighbors - sort of. I live in Garland.

The 400 is a great choice if you're after power. 400 blocks are stronger than 455's, and they can be stroked to 460+ inches using off the shelf parts. A lot depends on the rest of the car (transmission, gearing, converter if it's an automatic, etc.), what you want to do with it, and (of course) your budget.

I'm in the process of restoring my 69 GTO, and built my original 400 into a 461. How does this dyno sheet grab ya?

Bear
 

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Hot Rod,

Welcome to the higher "side" of GM performance!

Based on your comments, first things first. Get Jim Hand's "How to Build Max-performance Pontiac V8s" published by SA Designs. This is the only current "study" of the ol' Injun (what we affectionately refer to the Pontiac as). Learn the history and the strong and weak points of the engine. Identification of parts is also covered there, to a point. It IS 7 years old now, so some of the info is a bit "dated", as we're constantly evolving the engine. The "base" combo Jim uses is also very "specific", so some of what he did doesn't apply to all builds.

Ames Perfomance is, IMO, the best source for "things Pontiac", such as the emblems and decals you're talking about. Performance Years is another really good one. These are the only two I know of that don't also sell Chevy parts. Year-1, Classic, OPGI, The Paddock, all sell Chevy stuff, and you MIGHT get Chevelle stuff because "it fits".

The Tempest is a great platform for a performance car. Once you determine exactly what you have to work with, we can "steer" you to a good build.

Jim
 

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welcome to the herd Hot_Rod...That can be one hell of a sleeper car...:agree the stripes are unique....look kinda like Yenko stripes, i would do them again when you paint it. And you can take it to the bank that they look good if you get 100% thumbs up around here from all us purists....most stripe jobs get shot down immediately, but that looks "Right" on that car. i would look for a pre 75' 400 block as they were stronger castings, the motor guys will help you build a motor on paper within a set budget(Mr. P-Body & Bear are always very knowledgeable in real world applications for our motors and are most accommodating with help and suggestions). I am a Tempest/Lemans guy too...gives you a little leeway to customize it (stripes, etc.) since it will not effect the value as it would a true GTO. Am trying to work a deal now for a 70' Judge originally Orbit Orange RAIV 400, if i get that car it will be a concourse resto to original, and the 66' Tempest will be my whipping post....:D

1966 Tempest pictures by instg8ter - Photobucket

Brian
 

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Discussion Starter #10
Howdy Hot Rod, we're neighbors - sort of. I live in Garland.

The 400 is a great choice if you're after power. 400 blocks are stronger than 455's, and they can be stroked to 460+ inches using off the shelf parts. A lot depends on the rest of the car (transmission, gearing, converter if it's an automatic, etc.), what you want to do with it, and (of course) your budget.

I'm in the process of restoring my 69 GTO, and built my original 400 into a 461. How does this dyno sheet grab ya?

Bear
Thats very nice. That possible with a 78 t/a 400 rated at 200hp? lol
Cause I did end up getting it, couldnt pass it up cause it didnt cost me anything but time to pick it up and trade for my 350 sbc I didnt need anymore.
Hot Rod,

Welcome to the higher "side" of GM performance!

Based on your comments, first things first. Get Jim Hand's "How to Build Max-performance Pontiac V8s" published by SA Designs. This is the only current "study" of the ol' Injun (what we affectionately refer to the Pontiac as). Learn the history and the strong and weak points of the engine. Identification of parts is also covered there, to a point. It IS 7 years old now, so some of the info is a bit "dated", as we're constantly evolving the engine. The "base" combo Jim uses is also very "specific", so some of what he did doesn't apply to all builds.

Ames Perfomance is, IMO, the best source for "things Pontiac", such as the emblems and decals you're talking about. Performance Years is another really good one. These are the only two I know of that don't also sell Chevy parts. Year-1, Classic, OPGI, The Paddock, all sell Chevy stuff, and you MIGHT get Chevelle stuff because "it fits".

The Tempest is a great platform for a performance car. Once you determine exactly what you have to work with, we can "steer" you to a good build.

Jim
I've looked at all those sites and I cant find any tempest badges. Only lemans and gt/t-37 badges. Hmm..
So paint it and have the stripes re-applied. I have never seen them like that before. Very unique.
Depends what it'll cost me, lol. These were actually painted when the car was repainted.

As far as classic cars go I'm an orginal kinda guy, hence why I dont much care for the stripes. But thats just me, lol.
welcome to the herd Hot_Rod...That can be one hell of a sleeper car...:agree the stripes are unique....look kinda like Yenko stripes, i would do them again when you paint it. And you can take it to the bank that they look good if you get 100% thumbs up around here from all us purists....most stripe jobs get shot down immediately, but that looks "Right" on that car. i would look for a pre 75' 400 block as they were stronger castings, the motor guys will help you build a motor on paper within a set budget(Mr. P-Body & Bear are always very knowledgeable in real world applications for our motors and are most accommodating with help and suggestions). I am a Tempest/Lemans guy too...gives you a little leeway to customize it (stripes, etc.) since it will not effect the value as it would a true GTO. Am trying to work a deal now for a 70' Judge originally Orbit Orange RAIV 400, if i get that car it will be a concourse resto to original, and the 66' Tempest will be my whipping post....:D

1966 Tempest pictures by instg8ter - Photobucket

Brian
As far as what I'm looking for I just want to be in the 400hp range and have good streetibility. Probably stick with an orginal 350/3-speed and a stockish rear gear.

Budget is kinda limited maybe less than 2500$ range.
 

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Thats very nice. That possible with a 78 t/a 400 rated at 200hp? lol
Cause I did end up getting it, couldnt pass it up cause it didnt cost me anything but time to pick it up and trade for my 350 sbc I didnt need anymore.
Absolutely it's possible. You can take that 400 block, put a good stroker assembly in it, plus a good set of ported aluminum heads, add enough carburetion to feed it, an exhaust system good enough to let it breathe, and a cam/valve train aggressive enough to put it all to work and you'll be making a lot MORE power than I am. It all depends on what you want to do, and of course there's that famous A.J. Foyt quote: "Speed costs money. How fast do you want to go?"

Bear
 

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Discussion Starter #12
Aluminum heads huh? I was told you can make more power for less in some cases with certain heads from other pontiac 400's. I was recommended 6x heads or ram air 3/4 heads(If you can get them, kinda rare I hear lol)

What aluminum heads are popular choices for these engines?
 

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Aluminum heads huh? I was told you can make more power for less in some cases with certain heads from other pontiac 400's. I was recommended 6x heads or ram air 3/4 heads(If you can get them, kinda rare I hear lol)

What aluminum heads are popular choices for these engines?
There are lots of choices out there, with more coming all the time. Edelbrock was one of the first with heads that mimic (but improve on) the original Ram Air IV round port design, but have the additional advantages of having larger chambers (less compression), hardened exhaust valve seats (unleaded fuel is no problem), and can be ported by someone who knows what they're doing to make crazy power. Dave Wilcox who works with Mr. P-Body is one of the best their is.

Edelbrock has a brand new D-port head out now that's just now coming to market.

There are others, like Tiger, Kauffman, CV-1 ---- some get pretty radical and need special manifolds/headers due to a completely different port layout.

There are guys building race-only Pontiacs using these heads and aftermarket blocks making crazy power "on the motor" --- 1000+ HP.

Jim (Mr. P-Body) can build stroked 400's that are happy on 93 octane, run on the street, live forever, and make 550-600+ HP without even trying hard.

I've got real 1969 Ram Air IV heads on my motor. Yeah, they were silly expensive and they're very hard to find. I bought them many years ago, before even the first Edelbrock's came out. I like them and really wanted to run them just because of the "cool" factor and the stealth factor, but honestly, a good set of ported E-heads will put them to shame, power wise.

Bear
 

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Discussion Starter #14
I see. I was told by a friend to go with 6x heads, 068 cam and it be a great setup.

Also is the edelbrock torker a good intake? My current 326 has one on it and was wondering if its any good and will it work on my 400 as well if its a good choice for an intake.

I'd be content/happy if I can get 400ish-hp rather cheap and easily which I'm sure thats a low number for these monsters. :)
 

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I see. I was told by a friend to go with 6x heads, 068 cam and it be a great setup.

Also is the edelbrock torker a good intake? My current 326 has one on it and was wondering if its any good and will it work on my 400 as well if its a good choice for an intake.

I'd be content/happy if I can get 400ish-hp rather cheap and easily which I'm sure thats a low number for these monsters. :)
Well, that's one of the "old school" approaches, and not too bad if you're on a tight budget. Depends on whether you're talking 6x-4's or 6x-8's. The 4's are a decent combination on a larger motor, like a 455+, but on an otherwise stock 400 they're going to be down around 8.5:1 - which is too low. On a stock 455 with "the usual" deck height and stock pistons with valve reliefs, they'll be right at 9.5:1. As far as factory D-ports go, they aren't bad. They've got the larger valves, screw in rocker studs, and are new enough to have hardened seats for unleaded fuel. Skillfully ported and put on a motor with the right cam and enough compression, they're not bad on the street, but they aren't going to run with a good set of round ports or come anywhere close to a ported set of aluminum heads. 6x-8's are too big for anything, really.

The 068 cam is the Pontiac Ram Air III cam. It was common to recommend that one in combinations where the Ram Air IV (041) wasn't well suited, like in a heavy car or in a car that didn't have "enough" torque converter and/or gear to let the engine rev quickly and get up into the 041's power band. The 068 is a fair to decent street cam, it's going to have a nice smooth idle and will make plenty of vacuum for running things like power brakes, but it's not going to get you to the numbers you're looking for, I don't think. Both the 068 and 041 have been eclipsed by more modern cam profiles, but you'll still find people who "swear by" both of them.

There are two Torker intakes, the original Torker (now usually called the Torker I although Edelbrock never called it that), and the Torker II. Man, you've opened a can o'worms with that one. You'll find very opinionated and passionate people on every possible side of that question, and hanging off the edges by their fingernails too. Bottom line is, the way any manifold works on an engine is going to be greatly affected by the personality of the engine, cam, heads, displacement, rpm range, exhaust system, vehicle weight, gearing, and a ton of other stuff - it all affects how any given manifold is going to work so right out of the box you just can't say that "manifold a" is going to "always" run better than "manifold b" on every motor. It just doesn't work that way.

"Generally speaking" any single plane manifold like the Torker I and Torker II (and others), is going to tend to do better at higher rpm than a similar dual plane intake like the factory cast iron one, the Edelbrock Performer series, and others. They're also going to tend to not make as much torque/power at lower rpm as a good dual plane will. There's no such thing as a free lunch. What you gain at one end of the rpm range you're going to lose at the other end.

When I was working on building my 461, I ran across debate after debate after debate on "the manifold topic" - it's been going on forever. When I got my engine ready to go to the dyno, I happened to have both a factory iron intake that I'd port matched to my heads, and also a port-matched Torker I. I made dyno runs with both manifolds, chaniging NOTHING on the motor except removing one and installing the other.
Here's my "best" run using the factory iron intake.
Here's my "best" run using the Torker I

That was on my 461 with 93 octane fuel. It has 9.46:1 compression, a good set of ported Ram Air IV heads, a solid roller cam (236/242 @.050, 110 LSA, 106 ICL, .377/.381 lobe lift, 1.65:1 rockers), Doug Thorley 1 7/8" primary headers, and an 800 cfm 455-SD Qjet.

I draw 3 conclusions from the numbers above:
1) I lost bottom end torque with the Torker I, as expected
2) The motor "hung on" longer at higher RPM with the Torker I, as expected
3) Difference in peak horsepower "wasn't much"
4) I like the torque curve with the factory intake better. It's better suited to how I'm going to be driving the car most of the time. If I was going to be racing the car a lot, I'd probably go with the T1 and try to optimize the carb to take advantage of it.

What you can't read from the numbers is how it ran. The motor sounded "happier" and stronger on the factory iron intake than it did with the T1. It's very possible that's because I made no attempt to tune or re-jet the carb to try to optimize for the T1, I literally just swapped manifolds and ran it.

Again this was just one specific result on my engine. On a different engine, the results could be completely different.

Bear
 

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Discussion Starter #16
Very interesting indeed. I looked at aluminum E-heads and there 2k$. Is that what's expected to pay for those? Or is there cheaper better places to get'em?

I definatly want a setup that will net me over 400hp. Maybe even your setup, I like your numbers.
 

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Any good pair of aluminum heads (new) for the Pontiac will cost about $2,200-2,500 "ready to run". The "out of the box" versions always leave a lot to be desired, both from a "flow" outlook, and the quality of the hardware used in the final assembly.

For a 400-410 CID engine, 6Xs are not a real good choice, as the chamber volume is HUGE. The earlier heads with 72 CC chambers are much better suited. A relatively small "dish" in the piston makes them "pump gas friendly". Heads like 12, 13, 16 ('68), 48 and 62 are excellent for the 400, and relatively available yet. They all have the "D-port" exhaust flange. The Ram Air heads are even better (like Bear's). For a larger CID, the 6X can be modified to perform quite well.

It's a piece of pie to build a 400 HP 400 with D-ports (mild porting) and a good camshaft, along with good intake and exhaust.

ALL the factory grinds are antiques. While there are some still advising the use, they aren't professional engine builders. Modern cams, especially where compression has been reduced, are FAR superior. We (CVMS) like Comp XE grinds. Lunati VooDoo and Bullit grinds are also very good. The "key" is they all sport "assymetric" lobes, unlike earlier designs.

Jim
 

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Discussion Starter #18
If I can get iron heads that perform well and produce the hp I want, cheaper than aluminum heads thats the way I would wanna go.

Doesnt have to be crazy fast and make gobs of hp cause quite frankly I've never really had a car with alot of power, lol.
 

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Hot Rod,

For comparison purposes, when we (CVMS) "do" a pair of iron heads, they go "out the door" for about $1,500. That includes all the hardware and port work. It does not include the heads, themselves. It matters not, which iron D-ports. That gets new SS valves (1-piece, premium), new guides (real ones, not those cheesy liners), new springs "matched" to the cam to be used, good retainers and locks (10 deg), positive seals, and new "BBC" rocker studs. We reuse the Pontiac guideplates. They flow in the 240 range at .600" lift, and 200 on the exhaust side. Plenty of cylinder head to make 500 HP on a 455-plus engine, and 400-450 on a 400. Even more when combined with high compression and race gas.

Compare that to others, and to the cost of the aluminum heads. Then you have an idea of which "way" to go. I think you'll find we're about the same price as most other shops familiar enough with the Pontiac to do a superior job.

Jim
 

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Discussion Starter #20
Hot Rod,

For comparison purposes, when we (CVMS) "do" a pair of iron heads, they go "out the door" for about $1,500. That includes all the hardware and port work. It does not include the heads, themselves. It matters not, which iron D-ports. That gets new SS valves (1-piece, premium), new guides (real ones, not those cheesy liners), new springs "matched" to the cam to be used, good retainers and locks (10 deg), positive seals, and new "BBC" rocker studs. We reuse the Pontiac guideplates. They flow in the 240 range at .600" lift, and 200 on the exhaust side. Plenty of cylinder head to make 500 HP on a 455-plus engine, and 400-450 on a 400. Even more when combined with high compression and race gas.

Compare that to others, and to the cost of the aluminum heads. Then you have an idea of which "way" to go. I think you'll find we're about the same price as most other shops familiar enough with the Pontiac to do a superior job.

Jim
The heads I have on the 6.6 I picked up are stamped 54, they have the 2.11 valves, are those d-ports also?

The site I go to for casting #'s has nothing on these heads or the 6.6 I picked up. It's a WC coded motor with the familar 400 casting number.
 
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