DSRxCandyh2bEG

iTrader: (4)

This might be a newb question, and Im going to appologize already just in case.

I have an h2b eg and I tuned on 100 octane with a stock intake manifold and made 263 with 178 tq which was nice for my setup.

12.5:1 comp with a slightly decked head, less than .030 and I have flat valves. I'm thinking the comp is around 12.8:1-12.9:1 so its not super high...

Last night i did some base runs with 91 octane, my tank was empty and all I had was 91 octane in the area so I had to tune with it. I did a baseline: somewhere around 253 and 170tq.

I swapped out intake manifolds and put on a skunk2 intake manifold and base lined at 262hp and 174 tq with a slightly weaker curve than before. After tuning, DNR was able to bring it to 266hp with 173tq and a better curve than I had before.

My question is, would it be worth tuning again with 100 octane, have people seen dramatic differences with pump gas vs 100 octane or higher? Should I be running 100 octane with my compression or is 91 still considered safe? Any help is appreciated. Thanks in advance!

b20vtech

if u can advance the timming without any engine pining or denating, then i wouldn't see why u'll need the 100oct.

DSRxCandyh2bEG

iTrader: (4)

I'll compare my old dyno sheet to my new one and maybe ill post it in here to get more feedback...

00MRSi

Can you list your setup?

DSRxCandyh2bEG

iTrader: (4)

Setup:
92 h2b EG

Block:
95 mm crank with h22 rods
88mm 12.5:1 CP pistons with custom relocated wrist pin.
IB ultra light rods

head:
ported by blacktrax performance
supertech flat valves
portflow Ti retainers and valvesprings
blox B cams
Milled .020 at the most.

Skunk2 Pro Series Intake manifold and STR 70mm TB.
camp 1320 h2b header

Trans:
2000 b16 with an obx diff...


Thats it for the most part...




Modified by DSRxCandyh22EG at 2:28 PM 10/6/2008

Boots

the rule of thumb i was always taught was use the lowest octane fuel that you can without pinging for the best power