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Discussion Starter · #1 ·
I tried to revive an old thread, which detailed my current cam, but it didn't seem to work, so here's a new one.

67 GTO, numbers matching 400 with TH400. Engine was recently rebuilt with great stuff, but my uncle used a super mild cam, and now Im crying the low performance blues.

I've tweaked the carb, the dizzy and timing, exhaust, intake, ignition, and tire pressure! There's no performance left to get out of this thing. It was dyno'd at 360, which I find hard to believe, because I hopped it up a lot more and it still feels lackluster.

I'm looking to swap the cam with a full roller, but would prefer to not mess with the valve springs.

In my research, the Pontiac 041 cam seems like it would be a massive upgrade over what I have now, yet still be tame for the street. Any ideas?

I plan on pulling the nose to do engine bay paint, so Id like to get it and knock it out then.


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Below is what I used on an engine I just built. 462, 10.25:1, #16 heads not ported, edelbrock performer rpm, 1976 quadrajet totally worked over by Cliff, 1.5 roller rockers. 500 hp at the Dyno at 5,200 and just under 600 ft lbs at 4,200 rpm. I would choose the same roller over if I could. Solid idle at 800, lope but stable. Mostly street use. 2,400 stall converter, turbo 400. DUI performance distributor.

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I tried to revive an old thread, which detailed my current cam, but it didn't seem to work, so here's a new one.

67 GTO, numbers matching 400 with TH400. Engine was recently rebuilt with great stuff, but my uncle used a super mild cam, and now Im crying the low performance blues.

I've tweaked the carb, the dizzy and timing, exhaust, intake, ignition, and tire pressure! There's no performance left to get out of this thing. It was dyno'd at 360, which I find hard to believe, because I hopped it up a lot more and it still feels lackluster.

I'm looking to swap the cam with a full roller, but would prefer to not mess with the valve springs.

In my research, the Pontiac 041 cam seems like it would be a massive upgrade over what I have now, yet still be tame for the street. Any ideas?

I plan on pulling the nose to do engine bay paint, so Id like to get it and knock it out then.


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My advice is call Comp/Voodoo/Crower directly. Their phone support is great and they can get you a more customized cam for your situation/wants. I didn’t see it, but you’ll also want your rear end gear ratio handy. Unfortunately if you want a custom grind right now it’s going to be a big wait as they’re months behind due to lack of steel plugs (I’m currently more than 6mos on a Chevy cam right now). It sure would be nice if we made crucial products in this country again, like steel…
 

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Discussion Starter · #5 ·
Thanks for the input, everyone. The rear is 336... The car should be much faster than it is, so even just a ram air cam should be a big improvement. Frankly Im not sure how the builder got 360 on the dyno with this thing. Either that or Im just spoiled by my last few new cars, which were pretty quick.

There's no seat of the pant thrill, like my original 67. This car is responsive, smokes the tires, chirps the gears... it just doesnt pull like it should.
 

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Maybe you could find a place to get a car dyno and look at the numbers, what about transmission gearing, can you change that? Mines a 4 spd so it's different I think you said yours is an automatic but I have a 3:42 rear but a 2:98 first gear and gets up out of the hole quick.
 

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Discussion Starter · #7 ·
As I suspected when I posted, there are just too many variables. I appreciate everyone's suggestions, but above all else, I'm looking for a cam that will work with my existing valves/ springs/ pushrods. Cause if I have to start swapping out all of that stuff, then I might as well just pull the engine and do it all.

Most of your engines have 30-50 cubes on me, so it's doubtful that my requirements would be the same. Right now the car runs solid, so I suppose I'll attack the transmission swap first, then the fuel injection, then see where Im at.

I was just hoping that there was an obvious cam choice for my setup, that I could swap in when I pull the front end to do paint detailing
 

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Discussion Starter · #8 ·
Here's what Butler recommended

Butler has had proven results with Comp Cams. These cams are custom grinds that we stock on the shelf. This takes the headache out of trying to get the custom grind for your application. We have spend lots of resources perfecting the components of our proven engines and these cams are the common grinds you will find inside them. We realized that we were asking for the same custom grinds for our applications so we decided to stock what we use.
(HR) (Std Firing Order/ Std Journals) 288/294, 236/242, .521/.540, 114LS
Slightly more vacuum than a 112 and produces a little smoother idle.
 

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Discussion Starter · #10 ·
I know nothing at all about cam specs. The only thing Im an authority on when it comes to cams, is installing one on the side of the road, and incorrectly wiring a 4/7 swap. I can tell you whatever you want to know about either of those.
 

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Here's what Butler recommended

Butler has had proven results with Comp Cams. These cams are custom grinds that we stock on the shelf. This takes the headache out of trying to get the custom grind for your application. We have spend lots of resources perfecting the components of our proven engines and these cams are the common grinds you will find inside them. We realized that we were asking for the same custom grinds for our applications so we decided to stock what we use.
(HR) (Std Firing Order/ Std Journals) 288/294, 236/242, .521/.540, 114LS
Slightly more vacuum than a 112 and produces a little smoother idle.
i bult my engine 30 years ago puilding a pontiac was unheard of heads milled to increase compression comp cams solid cam split lift duration 510/520 290/300 sound great after sitting for 30yrs in storage changed fluids and fuel 12.4 at 108 at pontiac nationals
 

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Keep in mind anytime you put a new cam in you need to measure for push rods. You MAY get lucky and be able to use the same pushrods. But it’s not a guarantee.

Also, valve springs arent that hard to swap. With the knowledge you have on cars i have full faith in your ability to do a spring change. Dont let valve springs stop you from getting the cam or performance gains you desire.
 
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