[stockapearing455]

Originally Posted by tom s

Sounds like it in,drive it,if you hate change it.Tom

That's what I will do. If it seems ok,mi might try some roades lifters and maybe more converter.

[NeighborsComplaint]

Originally Posted by SD421

Big difference running a 455 long stroke vs a 400 short stroke motor. The 400 is already handicapped with low compression and the short stroke.

I agree, that Lunati cam is too much. Its like watching a football game finally getting good but its the last 2 min of the 4th quarter.

Now, Im no cam expert but I would either put Rhodes lifters in it to get the cam duration to act shorter or change out the cam for something with specs like 224-236 @ .050"and a tighter lobe separation (112). (Now the football game will get good in the early 3rd quarter) to get the intake valve to close earlier thus building compression earlier in the stroke. Getting a cam with a ICL (intake center line) around 110-108 helps build up the compression early too. Those Voodoo cams look like they would work great.

My two cents,
Don

True but I think it would be great at the track. A nice cam for this would be the Craje 283951 also.

[A.W.Dille]

I've been running this same cam in my 400 for years and I hate it, even with my 670 heads. I've been all over the board with cam timing on this thing and it doesn't make the power that one would expect and goes flat past 5200. Even though I don't have experience with the VooDoo cams I think they would be better than the single pattern BMII, even though I have an Ultradyne 280-288 on the shelf for a future 400 build, Lunati offers this grind also and may be a better choice but Harold Berkshire recommended at least 9.5 scr for this grind so may be a little lazy in the bottom end with the lower compression of heads. JMO.

[Cliff R]

We're currently building a 406 here with the Crower 60919 camshaft which has similar specs. We're shooting for 11 to 1 compression, and put the intake lobe at 107-108 centerline, which is what those camshafts need to be effective in the smaller engines.

At 8.5 to 1 compression they never make enough dynamic compression to work very well anyplace. The engine will not idle well, and be "soft" below about 3000rpm's. It may eventually pull pretty hard in the upper mid-range and top end, so you can run down the Honda Civic that just put two or three box-cars on you from a stoplight! Not trying to be a smart-ars, I've had several later model low compression 400's in the shop to tune with that same cam in them, and they are horrible.....FWIW......Cliff

[Tim Corcoran]

I second the Lunati Voodoo 10510702, 219/227 @ .050. You will build more dynamic compression with this cam and it will make more torque too. With this cam over your bracket master the engine will idle better, respond better off idle and will improve ET and MPH in the 1/4 mile. It's not just about duration at .050 and lift, with low compression you need to have valve timing that builds dynamic compression not bleed it off.

[stockapearing455]

Ok, so the verdict is this: the low end is worse(like expected) the top end feels good starting around 2800 rpm. The power brakes work most of the time, but it sounds good.
The cranking psi is 80. I do have a stock 13 inch torque converter in it now, hoping that a better converter will help. Maybe some rhoades lifters. Right now I'm happy. The top end feels better too.

[Stan Weiss]

Originally Posted by stockapearing455

Ok, so the verdict is this: the low end is worse(like expected) the top end feels good starting around 2800 rpm. The power brakes work most of the time, but it sounds good.
The cranking psi is 80. I do have a stock 13 inch torque converter in it now, hoping that a better converter will help. Maybe some rhoades lifters. Right now I'm happy. The top end feels better too.

Is that with all of the spark plugs out and the throttle wide open?

Stan

[stockapearing455]

No I just pulled one and cranked on it.

[Stan Weiss]

Originally Posted by stockapearing455

No I just pulled one and cranked on it.

You need to pull all 8 spark plugs and have WOT to do the test correctly.

Stan

PS - You should have min of 125-130 PSI

[b-man]

Originally Posted by Stan Weiss

You need to pull all 8 spark plugs and have WOT to do the test correctly.

Stan

With the engine at operating temperature as well.

Block the choke blade open as well if so equipped.

[stockapearing455]

So I ended up going from 35 degrees to 40 degrees timing. Really woke it up. Still a little lazy on the low end, but def feels stronger mid range and up top than the stock 066 cam. I could prob get away with this much because that cam is bleeding off a lot of cyl pressure I'm assuming.

[Ventura455]

Originally Posted by stockapearing455

So I ended up going from 35 degrees to 40 degrees timing. Really woke it up. Still a little lazy on the low end, but def feels stronger mid range and up top than the stock 066 cam. I could prob get away with this much because that cam is bleeding off a lot of cyl pressure I'm assuming.

I have an 8 inch 4000 stall tci converter I will make ya a good deal on it. It has just been freshened up. let me know. Steve

[NeighborsComplaint]

Originally Posted by stockapearing455

So I ended up going from 35 degrees to 40 degrees timing. Really woke it up. Still a little lazy on the low end, but def feels stronger mid range and up top than the stock 066 cam. I could prob get away with this much because that cam is bleeding off a lot of cyl pressure I'm assuming.

What I said earlier. Nearly identical cam to the Comp Magnum 290.

[Big Mike]

When I first started out with Pontiac engines, I found they were way different than Chevies. Yet I ran into plenty of Pontiac people who tried using pop up pistons, a big non-no with the stock combustion chamber. Some put a big camshaft in the engine with stock 2.73 gears and couldn't understand why the car ran worse from a start. Others went with a big 750 or 850 Holley and couldn't get past the bog with nothing more that a stock setup.

Point here is, no matter what the engine, things need to work together. You are doing well by asking advice. When I put an engine together, I make sure things are sized correctly for the application. Conservative well matched components work together to enhance the performance on a street driven car.

Because things work well and the car moves along smartly, you can just tell people it has a big cam or big carburetor. (Remember the 3/4 camshaft days.)

Generally speaking, the larger the camshaft, the more overlap and the need for compression. The RPM range generally moves higher to make power. So trying to get the engine to rev with a low numerical axle ratio or stock torque converter will be difficult and performance will suffer.

Just my opinion. Pontiac engines are big on torque. Unless you are all out drag racing, I'd keep components that work well at lower RPM. Not much point installing something that doesn't start working until 7,000 RPM when the stock redline is a thousand RPM less that that. There are a lot of fast Pontiacs running an 068 or 744 cam out there.

[Michael G]

Originally Posted by stockapearing455

Ok, so the verdict is this: the low end is worse(like expected) the top end feels good starting around 2800 rpm. The power brakes work most of the time, but it sounds good.
The cranking psi is 80. I do have a stock 13 inch torque converter in it now, hoping that a better converter will help. Maybe some rhoades lifters. Right now I'm happy. The top end feels better too.

You just answered your own question. " the top end feels good starting around 2800 rpm"
As mentioned and expected the torque curve is going to move up, and that's ok.
To get where you want to go you need to start matching the combo.
#1, You need to loose the stock converter.
Call Kris at Continental and order the tight 10" Continental Pontiac converter.
Great all around street/ strip converter that will treat you right and put the smile on you face.
Flash stall with this converter in your GTO should be right around 2800 rpm off idle and you will never know it's in there cruising down the highway.
3:55 gear with that cam just makes it in a 455. 4:10 would be optimum for the 400, but without a doubt do the converter first and don't cheap out with a Summit Saturday night special.
Good luck

[PunchT37]

Yep. Like ststed above. Either gear and converter it, or lose the cam with your bottom end. Depending on how much $ you want to put in it at this time, a cam is way cheaper than a set of gears, properly set up, and a converter.

[stockapearing455]

I think I will keep the cam, and work around it. I already have 3.55 gears installed. I'm going to have some fun with it, and I like the way it sounds. If anyone is interested I'm going to the track on New Year's Day and will post up some times.

[Tim Corcoran]

No matter what you do with your converter and gears, that cam you have in there with your low static compression is way wrong. If you had a time slip with the old cam and ran it down the 1/4 mile now with the new one you would be surprised how much slower it is now. Lots of guys have thrashing machines that won't even run a 13 in the 1/4 mile because they think a big cam will make their car faster. I would read Big Mikes post above about 10 times before you go out and buy a big converter to try and mike your combo work. You need to plan out a well balanced combo around your budget that will work with your static compression ratio with a cam that will build some dynamic compression.

[Ventura455]

Originally Posted by stockapearing455

I think I will keep the cam, and work around it. I already have 3.55 gears installed. I'm going to have some fun with it, and I like the way it sounds. If anyone is interested I'm going to the track on New Year's Day and will post up some times.

If you want my converter I would sell it to you and if you are not happy with it for any reason I will buy it back. I bought it through Jim Butler and I picked up .4 in ET and 5 mph over a 10 inch 3800 stall I ran before.

[72LuxuryLeMansLa.]

Originally Posted by Big Mike

Because things work well and the car moves along smartly, you can just tell people it has a big cam or big carburetor. (Remember the 3/4 camshaft days.)

I don't know how many times over the years I asked a Guy about his engine and his response is a slight shrug of the shoulders and he says "It's got a cam in it" I always reply the same way " I should F@#$%^g hope so! It can't run without one."