BIGJIM13

Guys
rebuilding an original 80 350 - I hear a lot about changing the cam for more HP - but does anyone have any specifics as to what cam and what increase HP one would expect?
Thanks

MotorHead

CompCams 270H and use a steel shim gasket to up the compression a bit, don't forget to spray the gasket with real aluminum paint, will gain you some ponies you can feel.

garygnu

look at comp cams extreme cam lines.they are newer hydraulic lobe design .what will you static compression be after machining and assembly ?get the cam last after you have all the other parts.with a 268 extreme cam pkg you mite gain 25 + hp over stock.hot rod did a budget write up and ended up using this cam.

BIGJIM13

MotorHead
Thanks
can you give anymore details? can I use stock lifters and all but just swam to a 270H -
Also - "real aluminum paint" ??
Thanks


CompCams 270H and use a steel shim gasket to up the compression a bit, don't forget to spray the gasket with real aluminum paint, will gain you some ponies you can feel.

BIGJIM13

MotorHead
Thanks
can you give anymore details? can I use stock lifters and all but just swam to a 270H -
Also - "real aluminum paint" ??
Thanks

63mako

Since your rebuilding it. Best upgrade for power and durability is a mild hydraulic roller cam. The Felpro 1094 gasket is a great idea and you will likely be installing new pistons. Go with flat tops at no additional cost. This will get you about 9.5 to 1 compression. Never reuse lifters. This is a great cam kit for the above build.
http://www.summitracing.com/parts/HRS-CL111145-10/
You will need a cam button for about $10 and new correct length pushrods. I would go with a new set of rocker arms as well. Comp roller tips are economical and sufficiant for your build level.

MotorHead

I was assuming he just wanted to change the cam, you need to new lifters too and aluminum paint has aluminum in it not just colored like aluminum

garygnu

use the proper break in oil.

cardo0

U choose a cam to match your combination - car, trans, gearing, compression ratio, cubic inches, heads, exh sys, etc. But your profile says u own a '93 vette which would make it a GEN II LT1. So who know what this '80 is going into? What kind'a power level are u trying for?
The word is out not to tell others to do "the search", but this is kind'a mystery to even get started on.

cardo0

tyancey00

Big Jim,
I was where you are 3 years back. you can have the motor warmed over with a 355 bore. that is a .30 cylinder clean up. Buy some nice Vortec heads and a good cam. it will run great and you will have a blast. I did. Then it wiped a lobe on the cam and i decided to go bigger. I stroked it. This was the best motor move i have made. it runs great. it does not get hot. it has all kinds of power and it is what i should have done in the beginning. I now pay a lot of attention to the oil and don't think i will have any lobe issues again...
what i am saying is spend some time with the machine shop and build the most fun you can afford. No reason to do it twice!

johnt365

Check out this post for my specific rear wheel dyno results for the Comp XE268H http://forums.corvetteforum.com/c3-t...mp-xe268h.html

The power was there but it took a 2800 torque converter and 3.55 rear gears to make use of the power band.

The heads I used are 60cc so a little more compression.

63mako

Stock 1980 has 3.36 or 3.55 unless it was ordered with the highway ratio. Very few were. Should work well with the combo I posted. Upping compression with flat tops really helps but better heads, exhaust, intake is the very best option if it is doable with your budget.

Dino_'72

Mako, would that retro cam work with old 492 heads, or would they need some special work done to them? Also, with over .500 lift, would rockers clear the stock style aluminum early style finned valve covers?

Don't mean to hijack the thread. Was thinking of going to an Isky mega 270 cam this winter, but rollers are now making me rethink my plans.

BIGJIM13

Guys
Thanks
sorry need to update my profile.
had a 93, now have a 99 + 2 projects 79 and 80
Sons and I took the 80 engine apart to clean and the question
came up...if we put in a bit better cam than stock, what would we get
and could we use all other original parts....
Thanks

hugie82

Motörhead has the right idea! But if it was me I think I would go with the 260 series cam with the stock carb and intake. Just because I like the low end torque and mid range

63mako

No problem with the right springs. I know beehives will work with stock length valves and pockets. I know Comp Roller tips with short polylocks will work with stock covers and some of the full roller rockers will work.

Dino_'72

Thanks for the info Mako. I know the heads have the Comp Cam springs recommended for their Xtreme line of cams. So should be OK.

With that roller higher lift, wondering if rubbing on guideplates or the pushrod holes may be an issue.

cardo0

Nail your compression now and target quench distance 0.040" - 0.050" then look for a cam. But for starters if using stock exh sys look at dual pattern cams with nearly 10 degress greater duration on the exh lobes. If not stock exh lets hear what u got.

cardo0

AirborneSilva

I don't know what you just said but it sure sounded perdy

gkull

Years ago I wasted alot of money fixing up my 79 L-82 882 heads with screw in studs, guide plates, porting, and tulip valves. I had 1.6 CC roller tipped rockers.

I had to snap and grind off the oil splash tabs of my stock valve covers. Low to mid .500 lift