jnew18

hey all,
I am just looking to see if anyone knows a ballpark crank ho number for my motor. its a 60s 327 block with the cast crank and rods, flat top pistons with 4 valve reliefs ( I think that's what they're called) the block has been decked and rebuilt by the previous owner. It's got 64cc aluminum heads ( https://m.summitracing.com/parts/mll-h8002k ), 1.6 roller rockers, a comp cams ex274h cam ( http://www.compcams.com/v002/Pages/389/XE274H-10.aspx) an aluminum edelbrock performer intake, and a summit 600cfm carb. It also has an ignition box and a msd dizzy. Does anyone have a ballpark hp number? Any suggestions to get more power?

Thanks,
wesley

cv67

auto or stick...what rearend gear do you have?
Whats your impression of how it runs now, where in the powerband are you looking to pick it up?

jnew18

It's a th350. I think the rear gear is 4.11. It also has headers and dual 2.5 inch exhaust with straight through mufflers. It runs good and pulls best in the mid to upper rpm range.
My base timing is 18 degrees and I have it all in by 3500. I'm just looking for more power, it doesn't really matter where it is in the rpm range as long as I don't lose any.

GUSTO14

Welcome to the Corvette Forum!

A lot of unknowns, but I would guess somewhere around 350 hp, + or -

Good luck... GUSTO

cv67

what size stall?
Know anyone who has a better intake and nice 650 double pumper laying around to try out?

jnew18

It's got a 2500 stall. I don't know of anyone with any parts laying around to try.

jb78L-82

What's the piston compression? Better aluminum heads will flow more air...AFR's. Roller cam with more lift....525/.525 ....easy 400+Gross HP...current engine 340-350 GROSS HP

super charged

What does auto or stick & rearend have to do with HP ?

jb78L-82

I thought the same....

Big Block Dave

Cuisinartvette has been around a long time here and the chevelle forum. Without speaking for him, Id wager that he was looking at auto vs stick and rear gear in relation to modifications to the motor to make more power, and not having a mismatch; I.e selection of a different cam.

Horsepower, especially estimated horsepower is just a number. Its certainly nice to have an idea of what kind of power could be made, but if the car doesn't perform, then what difference does it make. I talk to guys all the time that have 500+ hp 350s...or so they seem to think.

BKbroiler

:


Exactly. Big HP numbers don't necessarily mean impressive performance.

super charged

You dyno a motor to find out the HP. If you have a Q mile ET time and weight you can hit the Hp real close. Anything else is just a guess.

lars

I recently built a 327 spec'ed out as follows:
.040 over bore
Balanced
3-angle valve job on stock iron heads, milled to 64 cc
Molly rings
Forged flat top pistons
Comp XE262 cam
Performer intake
Speed Demon 650 mechanical carb
Headers
Turbo-Fire valve cover decals

This engine dyno'ed at 328 SAE Net horsepower at 5,000 rpm with 368 ft/lbs torque at 4100 rpm.

With the good heads and the 274 cam, you're likely 20 hp above this, and more if you're making power above 6000 rpm. That puts you easily into the 350 - 360 hp range. If you're running the standard Performer intake, it will limit your rpm potential, and therefore also your peak power, since it won't support a 6000 rpm engine.

Lars

71 Vert LS1

So with about 15% loss at the rear wheels so about 275HP?

lars

I think that's probably a good real wheel net number for a nice-running, well-tuned, performance 327.

Lars