i have a roller 350 i want to build. i want it to be able to keep up with a lt1 camaro. i have 041 heads, and i'm thinking of an lt4 HOT cam and a little under 10:1 compression. if i have to i might be able to get a set of vortecs which flow a little better than lt1 heads on the low lift side i think. how close do you think this would be to an LT1? aslo, do you think the rear end would hold up to it(84 non posi)?

 

If you are willing to put the effort into it you already have the right heads to build a 350 that will smoke a LT-1.



All they need is porting and larger 2.02 x1.60valves.

I think we've been through this before.

Use a Crane Powermax hyd roller or a Comp Extreme Energy hyd roller cam. They're better.

The rear end will last you many years if its built properly.
It is all critical to have the gears and posi installed properly by a trained professional.

A Power trax "no slip" locker will bolt right into your non-posi rear. This "posi" works very nicely. Its easy to install too.
The stock axles can be replaced with stronger Moser axles.

The rear will be strong enough to take the power of a 11 sec motor.
The stock axles are sufficiant for a 12 sec motor.

 

would the comp XE270 be OK? its for a daily driver so it needs to be OK on gas. how much compression do you think i could get out of it with that cam? it'l have a 160 stat and a big 4 row radiator. right now my 283 stays right at 160 on the hotest days and it has a tiny 1 or 2 row radiator.

we have gone through this before but i'm getting closer now, i actualy have a roller 350. i just want to make sure i build it right.

 

The XR-270HR would be to smallest I'd go with.

Simular to the GM hot cam. Should have a more intense lobe.

I was leaning more towards the XR282HR witha a bit of rear gear and converter.

performer RPM intake.

Compression Ratio.:

You'll probabily hear a lot of jibe and hype about dynamic compression ratio and cam duration / overlap.

ALL fine and dandy for short dyno test runs and controled conditions.

But the reality is that a typical daily driven carbed hi- performance motor that has to run on available pump gas everyday without little cans of octane booster and tweeking the igntion timing performs the best with a true 9.8:1 compression on 92 octane and 10:1 on 94 octane. Reguardless of the cam timing.

You might get away with 10.1/ 10.2 some days but then again you may not. Too much compression will lead to detonation lost power, a short engine life and more problems than its worth.

You want to build your motor to spec but not over.

This compression ratio will return the best overall performance with reliability.
Have the block decked to get the piston deck clearance nice and snug (.035/.045") including the gasket. More power here than trying to ride the edge with too much compression than is practical. or nessessary.

A LT-1 EFI motor can run a little more CR because it is computer controled, has a knock sensor,and a reverse flow cooling system.
And aluminum heads. But your motor is not an LT-1.

But don't sweat it or compare the two. Your motor is more heat efficient with its cast iron heads.

What octane gas are you planning to use?
Whats available in your area?
If you can get Sunoco 94 I recommend it.
If you can get Sunoco GT-100 even better.

A friend if mine has a relitively simple budget built 350 with moderately ported 041 heads in his 1981 Camaro.
An easy combo to duplicate.
Car runs 12.75 @105 all day long. Out of the box 750 Edelbrock carb.
No tuning. My famed ported 305 heads outflowed his on the flow bench. (more porting) But his worked very well.
Flows way more than factory LT-1 350 corvette heads.
His car has a rough racey idle (fairly big solid cam) but is suprisingly good on gas even with it's 3500stall and 4.10 rear gears.


All in the proper set up of the ignition timing and vacuum advance.

We drive it to the track and back and raced it all day.
This car is good for low 12's with tuning.
Does not even have a roller cam.
Compression ratio is just 10:1.

You need no more than this.

If your interested in the exact recipe to build this combination send me an email. It's pretty basic. You have some of the parts already. (Flat top 350 and the heads.) You could easily port your heads to this performance level yourself at home.
Then take them into a good machine shop for a valve job etc.

 

if i got with the 282 cam, the 041 heads(i probably wont port them, i'd rather have someone who knows what there doing work on them), short tube headers, probably a performer intake(i have a single plane if you think that would help much) and i have a 600cfm edelbrock carb for now about what would i be at compared to an LT1?

 

Oh, about half way there.

 

i think its a little more than half way there my 283 with the 041 heads, a cam with 204/214 duration and about 9:1 compression is more than half way there.