vetteguy112233

I was told by GM Performance parts that with a simple port and polish and a new cam, my motor could easily make 600HP. Any thoughts on this?

How much should a port an polish cost?

Next question would be what cam should I get for maximum HP? There may be more to this, but I know as much about cams as I do rocket science. I pulled these specs from Summit's website: This camshaft has 0.527 in. of intake lift, 0.544 in. of exhaust lift, and 110 degrees of lobe separation. Duration at 0.050 in. of lift is 224 degrees for the intakes, and 234 for the exhausts.

Any help would be appreciated.

SHAKERATTLEROLL

Call UD Harold is the Voo Doo designer and now works for him self once again. Great guy and will not steer you wrong. Sent you a pm with the info.

427Hotrod

We'll need a LOT more info than that to help pick a cam. How do you like to drive, intended usage, trans, gears, other mods, headers etc etc etc.

All that said, that cam isn't enough of an upgrade to warrant pulling the old one out. The 502 will respond well to a cam change and some good porting on the heads will really wake them up as well. You could get to 600 Hp with just a cam change but it would be a nasty solid roller most likely. A better intake and carb will help too.

But you are on the right track, because the ZZ502 cam is very weak and just about anything will improve things. The rest of the motor is great and can handle the power..just needs help breathing. Do some searching on Car Craft, Hot Rod and Popular Hot Rodding websites. They have done a lot of playing on the 502s over the years.

JIM

Les

Would you mind sending Harold's info to me too? I lost track of him after he left Lunati.

Ironcross

For some real good "trouble free" HP the mechanical flat tappet 454 LS7 cam part # 3859180 will really liven it up with valve spring # 3916164. But what do I know, right.

norvalwilhelm

That cam is a baby. I have a very mild roller cam and it is .621 lift and 236/244 @ .050 and it is considered mild with a very conservative lift.
I would be looking in the .630-.680 lift range for longevity on spring life and duration in the high 25? or low 260 range @ .050
Lobe seperation in the 110-112.
The comp 288R is a very popular cam but also very mild.
Jim could really help you here.

SHAKERATTLEROLL

PM sent hope you can catch him. He has been very very busy.

vetteguy112233

Ok, my mods include:

Edelbrock Air gap intake
K/N 4" Air filter
Royal Purple synthetic oil
Speed Demon 850
Hedman headers
New exhaust with Flowmaster mufflers (no cats)
HEI distributor with MSD ignition module
Accel super coil
MSD 8.8 wires
Tranny = Original 4 speed, but should soon be a new TKO 5 speed
I'm thinking I still have the stock rear end and gears, but not 100% sure
Aeromotive fuel pump

I like to drive the car on any warm/nice day that I can, that rarely happens because living in Utah only allows for 1/4 of the year of good driving days. I like to take it to the track to see what it can do and race anyone anytime that I can. I have family that lives about 300 miles away and would like to take it to see them once in a great while.

I hope this helps, let me know what else you need.

427Hotrod

Yes that does help some. What trans do you have and what gears? If an auto, what converter?

The Air Gap will be killer into the 6000 rpm range. What size headers?

I'm guessing that you would prefer to stay with a hyd roller cam? While I'm not a giant lover of them, they can work well in your rpm range. (At least what I'm thinking you might like) That would actually be a cheaper change too. you could reuse your old lifters.

Are you really thinking of getting heads done? If so, a little milling could get compression up some and that would help. Those heads can flow into the low-mid 300cfm range and make in the 650 Hp range pretty easily. Any work really needs to help the exhaust side. They will make excellent TQ but will run out of air as RPM climbs. My experience with the ZZ502 is that it is pretty much done by 5500 rpm in stock form. Power noses over quickly after that. A change to a nice streetable solid roller and the valvetrain to go with it will have it pulling to the 6500+ rpm range easily. But I'm still not thinking that is what you are looking for.

I'm thinking somewhere around the Lunati Voodoo line. Maybe the 60212. It's 231/239@.050 and.600/.600 lift on a 110 LSA. The 60204 is a 233/241@.050 with .554/.572 lift on a 110 LSA. I would err to the .600 lift to help heads breathe. Lift doesn't hurt any driveability issues at all. You could also look at the Comp line....but I didn't see anything that jumped out at me for your deal.

Either way I think you will want to be in the low-mid 230* range and at .600 or slightly more lift. Depending on what else you tell us about your needs we would play with LSA some to narrow down manners and rpm range. You can order the cam with whatever LSA you want. You might go out to a 112 to smooth it out some. Cams in this range will have a pretty good lope, but will be reliable and make good power. You definitely need to ck clearances on valvetrain and you will definitely need better springs. The Comp beehive deal might be Ok with light retainers, but double check with cam folks when ordering.

JIM

vetteguy112233

I have the stock Borg Warner 4 speed transmission and absolutely no clue on the rear gears. What would have came stock in a 78? If I remember correctly the headers are 2" tubes to a 3" collector, that actually runs 2 1/2" pipes to the flowmasters. I hope I remember correctly.

vetteguy112233

I was told today that the port and polish for the heads and exhaust will be $300-$325. This guy is highly recommended and seems to know his stuff. Is this a good price?

427Hotrod

We'll have to do some research on gears....could be anything from 3.08's on up to 3.73's maybe? I dunno.

I would do some research on exactly what that guy will do for that price. A whole lot of a good port job is a new valvejob to match the new bowl work. A "hacker" can do more damage than good in a port. You are already dealing with a pretty refined head. It just needs cleaned up and improved...not just ground on. I can tell you that just a good serious valve job will cost $200-$250 or so with no port work. You can easily end up with $750-$1000 in a good port job that gets some flow bench time. You will want to get before and after flow bench numbers to make sure you get an improvement.

You don't even want to know what it costs to get "serious" port work done!! Usually more than the heads cost!!

By the time you're in that range, these days unless you find a real good porter you trust, you have to start considering selling off the heads you have and getting a new set of CNC ported ones.

All that said, you have a decent set of heads now that can be made to work in the 6000 rpm range. Just follow up with head porter to really see what you will get.

Angle milling for compression and cutting intake face of heads to get intake lined up will also add to the bill.


Again, a cam change with your combo will provide excellent bang for the buck even without porting heads.

JIM

vetteguy112233

JIM, YOU ROCK!

Thanks for all of the great info. There are a few more people locally that I was told to contact, so I will do so on Monday. I will also do some more reasearch on the cam. Thanks to everyone else that has contributed to my post.

SteveG75

Gilbert Chevrolet, formerly Salle Chevrolet, sells a version of the ZZ502 called the Super Street 502. It is basically a 502 with ported heads and a bigger Crane solid roller cam.
Horsepower: 625 @ 5,900 RPM
Torque: 600 @ 4,600 RPM

Their website gets weird with the frames so try this link and then click around if necessary. http://www.salleechevrolet.com/frame...V8s/ss502.html

The site itself ist every part in the motor. Here is the cam:
Camshaft: Crane P/N 168601, Solid. Roller, Lift (.615” I, .636” E), Duration @ .050” (246° I, 254° E)

This might give you some ideas.

stavanger

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