Is 100 octane sufficient for a 125 shot? With good tuning would it even be possible to get by with pump 93 octane?

 

with the right tuning you could pull off a 100-125 shot... but you better have a built lower obviously or alot of luck.

your timing would have to be really conservative... and much cold plugs.

with 100 octane you coulf get by with a tad bit more timing.

 

Bottom end will be built with SRP pistons, Eagle Rods, ACL bearings, Golden Eagle blockguard. So 93 cotane would be possible?

 

you would be fine with stock bottom end , i pushed 100 shot many times on my stock motor R on 94 Sunoco pump gas.
i was ready to go 125 shot , but took the kit out for turbo

 

Yes, but I wanted to be safe, D series rods are known for being weak. So I guess 93 octane should be fine then. Would I see better performance out of high octane at the track?

 

not unless you up the timing , the higher octane is to allow more timing and prevent detonation at the upped timing . basically

 

So how much timing should I pull for 125 shot on 93 octane? Then, how much timing could I put back in for 100 octane?

 

with that big a shot on 93 octane the gains will be minimul from like a 75 shot. i ran a 75 shot in my car, on 100 octane and the car was pulling serious timing. for a point of reference, my buddy ran the exact same trap with a 50 shot and 75 shot on 100 octane, in a 01 gti18t. 107mph either way. you should really just run the best gas you can find for a big shot. mike

 

i did stock b18c1+100-125 direct port all summer (like 50 botle++$$$)94 octane whit no prob at all but i would have to say get a turbo kit its better invest and could be alote faster!

 

No turbo for now, not until my next project. Thanks for the suggestion though.

 

i ran 100-125 shot DP on a built B18C last year, no problems on 93 octane pump gas. your C/R of course plays a part when retarding the ignition timing, and even when adjusting the cam timing as well. if the C/R is on the lower side then 5-6 degrees of ignition retard should be all that's needed. but if the C/R is 11:1 or so then an extra degree or two may be needed. every seutp is a bit different so it's hard to say either way. you have to run extra ignition timing retard at first and then slowly bring the timing back. if you get any pinging or detonation then just back the timing up 2 degrees and you should be good to go.

 

I'll be running 10.5:1 C/R.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">I'll be running 10.5:1 C/R.</TD></TR></TABLE>

i don't see why 93-94 pump gas (if you have it where you live) wouldn't work fine.
you don't need the 100 octane race fuel, it's really not needed and would be a waste of $$ IMO. use pump gas and run the correct ignition timing retard for that, then when you want more power (at the track and w/e's) run the higher octane fuel like the 100 and bring the ignition timing to whatever point you can without detonation.

 

Thanks.

 

Ryan,

The bummer about using a dry setup is that you're stuck with whatever fuel you've got in the tank all the time. So unless you're only going to spray at the track you'll have to drive around with some $$ fuel on a regular basis.

With a 125 shot I would deffinately recommend upping your octane a bit. You want to slow down that burn.

Get yourself some Toluene or Xylene from a paint store and mix a couple of gallons in with each tank of gas. That'll be the cheapest way for you to get a reasonable octane rating.

Also since you're being so aggressive with the N2O I would suggest checking out J&S Safegaurd products. And also an MSD Digital Plus with the single stage retard so you can retard timing X degrees when you flip your Nitrous system master switch on.

 

Thanks for the info. I will be using a Hondata nitrous control to retard timing and adjust fuel appropriately and will just use an MSD 6A for additional spark. J&S Safeguard makes knock sensors right? I'm not really familiar with them. My car is OBDI now, would it still be able to utilize an aftermarket knock sensor?

 

A J&S safegaurd usually uses the factory knock sensor. It will then listen for knock and retard timing on the cyl that's knocking.

That way even if your timing settings in the Hondata are already pulled if there's a problem the J&S will pull more timing out.