ratman

what ci?
what hp?
what grade fuel?
what comp ratio?
what total timing are you running?

thx for sharing your info, rm

GOODT

total timing should be about 34 regard less, much more with pump fuel will cause problems, but I am very interested in the responses thanks good question

IRONMAN

510 ci
probably 525 HP never dynoed this one.
89 octane (I designed it for this)
10:1
34 deg

I spent some time optimizing the chambers, domes and quench so that I could run the 89 without any problems. I have also tested more timing and higher octane with no measureable increase in rpm. I tried 93 with 32, 34, 36 and 38 deg at 38 the power fell off some but at 34 the rpm's were the same as with the 89. the max rpm i have seen was with the 89 and the 34 deg it falls off at below 32 and above 36 so 34 is the sweet spot for my setup.

k24u

I am running 10 degrees advance at idle I built a 454 420cam clone running a balance and blueprinted forged pistons 8.79-1 comp, my heads are large oval ports ported and bowl blended big valves 10degree locks gold rollers eldelbrock rpm-air gap 750 carb thunderbolt IV ign turns 5000rpm bravo1 70mph 23 nova spyder

ratman

k24u what is your total timing at full advance? thx

offthefront

iTrader: (1)

How does that work ? Idle timing plus the advance of the ignition ? Like the T-Bolt 24* module ....10* at idle ?

Vinny P

I think we should include what heads we are running. Steel or aluminum? Also whether you have closed cooling or raw water . That can determine what water temps you run at. Most raw water are 140* closed 170*

NA 540
Closed Cooling 170* t-stat
680 hp
660 torque
MSD Ignition
9.25 compression
Aluminum AFR Heads
93 octane
36* total
NO detonation problems are evident

k24u

I am running a gm336781 large oval port heads cast iron these heads work fine on a gen V running a complete markIV valvetrain I think it is running 34 advance because of the module

mtgbiker

At what rpm should total timing be dead set? 2500, 3000,

BY U BOY

Gm 12363398 Oval Aluminum Heads 110cc/290cc
1.7 Comp Roller Rockers
Zz502 Cam
Marine Power Aluminum Manifolds/risers
Comp Retro Lifters
502 Aluminum Intake
Gm Performance Ignition 12* Idle 34* Set At 3500rpm
Raw Water Cooling
Holley 750
1991 7.4 Mark Iv Block