Cam and lifter choice 428 in a 1969 Grand Prix
 

I have a 428 HO being built for my '69 GP, I want to go with a hydraulic cam and eventually run it is a FAST or pure stock race. As far as lifters go, who should i stay away from, I'll probably end up calling bullet and Butler to see what they recommend. My goal is to put the car in the mid to low 13s with 722 heads, LB manifolds, factory aluminum intake, 3.55 gear and a small convertor. One cam I'm thinking about is the crower 60919 470 lift, 231/240 duration at .50.

That’s what I’m running in a 467 and I love it.

Talk to someone like SD455DJ first.

Crower 60243 is a small step down from the 60919 and in my opinion a better choice for a 428 in a somewhat heavy GP with 3.55 gears.

The Summit 2802 would be another one worth considering.

So 64speed, do you run your car in the 1/4 mile Fast or pure stock classes like the OP is looking to do?

Just wondering why you have experience in things like this, plus your giving recommendations from your motor which is 35 CID larger then his.

If you want to take full advantage of the intake flow of those 722 heads you need to run .500” to better yet .550” lift since this is where peak flow takes place.

You also you do not want to run the stock type Tulip intake valves, the tulip valve on the exh side is fine.

You want to run a D port type nail head intake valve.

Also not running the stock type Tulip intake valve with its big chamber side dish will help with out with compression.

Have a valve job done on the intake side that maxes out the full OD of that 2.11” valve.

Only use a 2 angle valve job that keeps the stock 30 degree seat but apply a 60 degree bottom cut that takes that 30 seat width down to .050” but no more then .055”.

I hope your intake manifold is one that was originally on a 400 because the latter production ones and the replacement off the shelf ones where had a shallower plenum and runners and due to that made less power.

I forget exactly when this casting change took place. But I think you can find this info still on line.
If you can’t let me know and I have it here somewhere and will dig it up.

Exh wise these 722 heads are sluggish due to there large runner area after the short turn.

Running exh manifolds will help this condition out especially if you take the time to open up the inlet of the exh manifolds such that they are 1/16” bigger then the exh flange area of the head.
If the exh manifolds have the meat make the bottom 1/8” larger so you end up with a nice lip on the floor to reduce the low to mid speed reversion that the excess runner area in the heads produces.

Valve job wise on the exh side max out the 45 seat OD
to 1.805” then add a 30 degree top cut.
This arrangement should leave you with a .030” wide top cut.

On the valve itself add a 30 degree back cut that takes the .100” wide seat area down to .075”.

If the Q-jet you will run was off a Firebird note that many of them had restricted secondary openings, so be sure to grind that limiting tang off.

Was it a recommendation or just a statement? I have dabbled in the track in my youth but no I haven’t been in years. I can tell by my ass dyno my car is faster than 13 seconds but by how much I don’t know. Yes I have 35 more cubes. I also have 1.7 BBC Chevy rockers and it’s still smooth as a babies ass at idle so I’m sure 35 cubes aren’t gonna make it unpleasant. Again just making a statement.

You can talk to Tim Goolsby at Ultradyne/Bullet about exactly what your needs are. He is tough to get in contact with though. Just keep trying. Morning is best. Your biggest challenge is going to be finding a cam core to grind. I just a week ago ordered one of my favorite mild cams from them. 276/286 on a 112. That's a nice cam and makes good vacuum for power brakes and good torque for a heavy car. A custom grind I had made for my old NMCA 4500 lb. car was a 276/284 on a 113. NMCA had a minimum vacuum rule in those days and this cam just made the grade. It propelled that heavy boat to 108 MPH trap speeds with a 421 back in the 1980's. Rules required stock heads, intake and exhaust manifolds. Enough for a class record. I have had good luck with Crower cam saver lifters. The extra oil on the lifter foot certainly doesn't hurt. Good luck with your engine.
If you have some old Pontiac cams, he may be able to re-grind one to meet your needs. Finding a new core is difficult and it looks like there may not be a new run of them by CMC for 2 or 3 years if ever.

Mike, what are the other specs on that cam?

Dennis

I'm not hating on you or anything, but running Big Chevy 1.7 rockers on your Pontiac? What heads and how did you correct the geometry?

Very cool ‘69 GP, and especially the 428HO’s. Well, unfortunately, you can’t run it at the Pure Stock Drags, the event in Michigan, anyway. There are other “pure stock” style races around the country where as long as it looks reasonably stock (no aluminum heads, aftermarket intakes, Holley carbs, and headers) your able to race. The F.A.S.T. rules pretty much let you do any modifications under the engine paint as long as it looks factory, but if they have a savvy tech guy, they may spot the RAIV 722 heads and just let you run time trial passes. Their Factory Stock class pretty much follow our rules (PSMCDR.org), but they may let it go as they are pretty lax about correctness a lot of the time.

Your D-port #62 heads are good as is the cast iron intake and give nothing up to a RAIV top end in the lower rpm range (idle to 3500 rpm). You need low end torque to move your relatively heavy GP and the 62’s will help there. With at least 10.0 to 1 compression, the 2802 cam (224/234/114 at .466”/.488”) is a great choice with Hy-Lift Johnson lifters. You’ll make the 16” Hg at 1200 rpm easily and your 3.55’s would work well a small converter. Any RAIV clone cam is not going to pass the 16" Hg. minimum and have a reasonable sounding 'stock' idle.

Dennis

Edelbrock Round Ports. My engine builder worked it out and got a good pattern

And your running these 1.7s on the exh side of that duel pattern Cam your running!

I fully do not see the need for that in terms of exh to intake flow ratio and really call into question your builders logic for doing so, especially with aftermarket round port heads.

I read the original post and thought the same thing with regard to it won’t be close to working for pure stock or even F.A.S.T. rules. I believe there is a stock class on the east coast that it could run in, pretty far from the spirit of most stock classes though. But it is a cool combination of parts.

Unfortunately it seems all the HFT lifter brands have issues right now, including HLJ. Nitriding the cam is cheap insurance against getting a set of 16 lifters that doesn’t have issues on 2 or three lifters in the set of 16.

Nothing to add technical, but wouldn't a 428 w/ 722's really be a 428 SD? HaHa :D

Are you relating this comparison to SD as in 421, or 455?

A 428 at .030” over is 432 CiD, so closer to a 421.

Maybe due to the round ports heads Ram Air is more fitting ?

Intake and exhaust.

To answer your Question: The exact cam I really loved is a custom grind. Here are the specs. Advertised is @.0045"

Adv. Intake 276 .050, 221 , .200, 132 lobe lift .3027

Adv. Exhaust 284 .050, 232, .200, 143 lobe lift .3273

ground on a 112-113

The exhaust lobe is a little aggressive but it made 7 more HP than an alternative slightly gentler exhaust lobe I will list below. We had to run the stock "093" heads which have small valves and poor stem angle. The exhaust flow is especially poor with the required exhaust manifolds. That cam really helped.

The alternative exhaust lobe, which is more gentle and popular, would probably work fine with the later heads. It is:

Adv. 286 .050 230, .200, 139 lobe lift .3027

These cams were easy on the valvetrain. I ran a 276/286 in a 421 HO 9 passenger Catalina wagon over 100,000 miles. Pulled a 19' Sea Ray probably 10,000-15,000 miles over many years to lakes all over OH, KY, TN. That wagon weighed 5050 Lbs. It ran 14.60's all the time with that cam. Turbo 400 and 3.42 rear.

I believe the best way to get good cam advice is go to an experienced Pontiac engine builder and ask him to spec out a custom grind for you and buy the cam from him. There are some good builder here. Paul K is one and there are others too

After talking to the friend of mine tonight who is building my engine, the 722s will have to be cut to around a 66 cc. The piston I'm using have a 14 cc dish, and not enough to kill off some compression, so it looks like the 62s might be what i'm going to use after all.