View Full Version : Chevy 388sb dyno results

02-19-2012, 06:41 PM
I'm Derek and i thought i'd show the results from a 388 sbc i just finished and dynoed thats going into a 86 camero for street/road race style driving, I try to build engines that make excellent average power in the rpm range they will be used in without breaking the bank
sure i could have made even more power with a bigger cam and Ported Victor Jr but i felt i could make a more user friendly setup with the parts we used fwiw
First we started with a 89 2-bolt one piece rear seal block
Fully Machined it, -.005 deck height 4.06 bore set main and rod clearance to
.0025 with ARP main studs
we then ported and blended the oiling system transitions in the block and rear cap.
Ported Melling m55 with Canton Road Race Pan and pick up
We used a Scat LW 3.75 stroke 9000 cast steel crank and 6.0 scat pro stock 4340 rods bushed with ARP 8740 cap screws
For Pistons we used Probe FPS forged 2618 alloy Flat Top 2vr pistons at 320$ a set there is no reason to use cast stuff anymore!
compression is 11.08:1 with 4cc valve reliefs, 67cc chamber .035 Quench
moly 5/64-5/64-3/16 rings standard tension nothing fancy
Fully Ported Edelbrock Perf RPM Heads flowing 280cfm at .600in 237ex at .600 with pipe on a 4.06 bore SF600 190cc intake runner
Edelbrock springs, GM LS7 lifters, billit dbl roller timing set and smith bros .083 wall 5-16 7.300ol push rods
trick flow 1.6x7/16 rr arms
Comp XR282HR 230-236 .540 .550 110lsa 106.5ilc
Performer RPM intake Non Air Gap, Modified Plenum and Port Matched
Holley 750cfm Ultra HP, MSD Dizzy, Hooker Headers 1-3/4 primaries
I Wish we went with the 850cfm Ultra, we had about an 1.5" hg of restriction so i'm sure it would have cranked out more with a bigger carb but either way i'm happy and so is the customer most importantly!
i'm trying to upload the dyno sheet but i'm having trouble, overal we made 493hp at 5800-6000 and 491tq at 4800 and average power at 425hp 475tq, not bad for no afr heads or using a bigger cam, superflow dyno, there is easily 500hp there and if i had more time i think she has aprox 510hp 500tq but still for not Spending much time tuning i'm happy, i'll post the video too, thanks

02-19-2012, 06:42 PM

02-19-2012, 09:12 PM
Nice power for a inexpensive build. Good job!

02-20-2012, 03:05 PM
not bad at all

Paul Huryk
02-20-2012, 05:39 PM
Very good numbers for a budget build!

02-20-2012, 07:15 PM
thanks! much appreciated! it should rock that camero pretty good!

Paul Huryk
02-21-2012, 05:12 PM
I just remembered that your engine put out similar output #'s to the 383 that was built in the John Lingenfelter SBC book.

02-21-2012, 07:33 PM
I'll Take that as a Compliment! Lingenfelter was a big influence on me!
here is a link to my facebook page with the dyno sheet fwiw

Paul Huryk
02-22-2012, 06:39 PM
I'll Take that as a Compliment! Lingenfelter was a big influence on me!
here is a link to my facebook page with the dyno sheet fwiw

Indeed it was a compliment...

02-23-2012, 04:17 PM
Hey did you port the heads yourself? I ask because the low and mid lift #'s must be great.

02-26-2012, 06:49 PM
Yes i do all my own Port Work
here is what these flow, i wanted to see if i could get a set of e heads near an afr 180-195 head and i think i got really close, if i used thev bigger 236-242 cam i would have a better comparrison to some afr head dyno sheets
.200 155in 123ex
.300 208in 170ex
.400 261in 205ex
.500 273in 226ex
.600 280in 237ex

02-27-2012, 02:03 PM
Very impressive low lift numbers, how much do you charge for porting lol

03-20-2012, 10:50 PM
What kind of gas mileage can I expect out of a motor like this behind a muncie m22 with a 12 bolt, 3.42s in a 3700lbs A-body? 20's?

03-20-2012, 10:52 PM
Also average rwhp? Is there a big loss in power going turbo 350 or 400? I brought up this thread at work, and they all started laughing at me claiming thats how much it makes to the motor and expect to loose around 100hp going thrue a turbo 350?

03-21-2012, 05:10 PM
my nova gets about 15 on the highway... it really makes 340ish to the tire with the new exhaust. i cruse anywhere from 3 to 3.5k

3.8k converter 4.10's and a th400... i run a 275/60/15 m/t dr (28 inch tall)

expect 20% and it goes up as you make more power through an auto, that is due to fluid copuling loss

03-21-2012, 07:04 PM
Yeah PM sent but we will know soon, The last 383 i built like this did 412rwhp 437rwtq through a 2500 stall 3.42 gears and light weight wheels on a mustang dyno but it had less cylinder head and slightly smaller cam so who knows, i just use the dyno for tuning and testing the track is where the bullshite stops lol