what to run 25psi what octane

[mudslinger7]

i am wanting to run around 25-28 boost psi what octane do i need to run or what do i need to do to make it possible i have a t52, 3.5 inch down pipe full exhaust, rjc power plate, #60injectors, trans + box, lt1 maf, ported polished heads, rjc bullet proof head gask, arp head studs, arp main studs rod bolts, comp 0.459 lift flat tappet with valve springs to match, stock inercooler, hard wire fuel pump accu reg, i have the ft extreme chip and a tt street chip

 

[TurboV]

If your going to use your car mostly on the street, i would suggest running Alky with 93 Octane. With a healthy car and a good tune, those goals should be obtainable. I would probably upgrade your intercooler also if possible, that will also allow you to run those boost numbers and help surrpress detonation. if you are thinking of tuning just with race gas, you will prob want 110+ Octane.(Still upgrade that intercooler). my $.02 P.S. you will want to reburn your chip for Alky.

 

[jcawley3]

alky kit

 

[TurboV]

If your going to use your car mostly on the street, i would suggest running Alky with 93 Octane. With a healthy car and a good tune, those goals should be obtainable. I would probably upgrade your intercooler also if possible, that will also allow you to run those boost numbers and help surrpress detonation. if you are thinking of tuning just with race gas, you will prob want 110+ Octane.(Still upgrade that intercooler). my $.02 P.S. you will want to reburn your chip for Alky.

Oh Yea.. Almost forgot... If you make these changes, you may need stickier rear tires.

 

[bison]

If your not using a wideband and at least 2 alky nozzles forget using alky for 28psi. Go with at least 110 octane. Nothing will make the engine last longer than c16 or better. Believe me if you get greedy with alky injection you will pay the price later. Without a way to data log and dial in exact a/f ratios you should not ever consider alky for over 24-25psi if using 93 in the tank. Q16 and alky works great at 10.8:1.

 

[mudslinger7]

so i can run 110 with out alky ?

 

[TurboDave]

so i can run 110 with out alky ?

No! IF you want to run race gas and no alky and expect to see boost levels of 28, then you'll be wanting to run 114. It's what I ran when I was racing on a regular basis. It handled 28# of boost and 27°-28° of timing.
You would want more octane than that if you go any further on either number.

 

[SMS]

Also make sure you are using a chip burned to handle the boost you want to run. If you run a street chip designed to provide fuel for 15-17 psi, and crank up the boost to 28 psi, you will have an extreme lean condition (bad).

 

[bison]

so i can run 110 with out alky ?

28psi on straight 110 octane and no alky no problem with 22 degrees advance. If you want to run as much timing as Turbodave did id go with more octane. Ive ran 30psi through 3rd on an 8:1 small cammed engine with 110 and no alky. Timing was 21.

 

[ronbuick]

110 octane on 28 psi, no way, alky and 28psi, your gonna need more than
1 nozzzle, with my 1 nozzle alky kit, 20lbs is all I felt safe with with all the scan tools I use, EGT, DS, scanmaster, WB02, best to use C16 and not worry about it, IMHO

 

[bison]

110 octane on 28 psi, no way,

ok bud .Have you ever ran 28psi? Post a data log if you have one.

 

[yullose]

Bison...

I'm curious how long your WB O2 sensors last when you run leaded race fuel.

I've run C16 before and loved it, but only used it with a Denso 1-wire sensor. (with great success)

I'd REALLY like to go back to C16 when I get my car together, but was concerned about WB O2 sensor life. I have two TT 6.0 chips burned for my combo... one is setup for 93/alky and the other is burned for C16.

If I can at least get a few months out of a sensor, I'd be happy with that.

(sorry to the OP for the hijack)

 

[northerngn]

E-85
i run 25 psi 24/7 the only change i make to the car when i go to the track is rear tire psi
see my sig
you may need more injector but its awesome having the car set to kill all the time
plus i dont have to worry about when my little tank of alchy runs out
my alchy tank is 16 gallons :tongue:
-dan

 

[ronbuick]

never benn t0 28psi, 26 is the highest I have ever run and that was on C16,
might have something as to why I have over 400 passes on this great car with out ever popping the head gasket, but it all depends on your balls and your love to working on or driving these cars, I prefer the latter, but now I;m done with racing and just want to drive and with my alky kit keep it in the 20 or so psi range, and should still run in the low12's which is good for me at this point in time, thanks.

Ron

 

[bison]

Bison...

I'm curious how long your WB O2 sensors last when you run leaded race fuel.

I've run C16 before and loved it, but only used it with a Denso 1-wire sensor. (with great success)

I'd REALLY like to go back to C16 when I get my car together, but was concerned about WB O2 sensor life. I have two TT 6.0 chips burned for my combo... one is setup for 93/alky and the other is burned for C16.

If I can at least get a few months out of a sensor, I'd be happy with that.

(sorry to the OP for the hijack)

Denso 1 wire is about the worst sensor you can run for closed loop operation. It is lazy as hell even when new. It may not throw a code when its fouling out but will still waste fuel. The wideband i run with my XFI has at least 8 tank fulls of 110+ leaded fuel on it and no problems yet. A one wire would be shot after about half a tank and some idling. The one i use with my LC1 lasted several years with regular doses of leaded fuel too but finally failed when coolant hit it. A replacement is $70 at any auto parts store. Once you get the tune right you really dont need the wideband unless you have correction off it. Just remove it and plug the hole.

 

[TurboDave]

Denso 1 wire is about the worst sensor you can run for closed loop operation. It is lazy as hell even when new. It may not throw a code when its fouling out but will still waste fuel. The wideband i run with my XFI has at least 8 tank fulls of 110+ leaded fuel on it and no problems yet. A one wire would be shot after about half a tank and some idling. The one i use with my LC1 lasted several years with regular doses of leaded fuel too but finally failed when coolant hit it. A replacement is $70 at any auto parts store. Once you get the tune right you really dont need the wideband unless you have correction off it. Just remove it and plug the hole.

Good grief! Finally somebody that has seen the same thing I've seen on every car I've looked at with a Denso in it!! I just quit trying to convince folks of how crappy they were for daily driving closed loop operation. Everytime I tried explaining it all I got was a lot of verbal abuse. All they can see is how well it does with leaded fuel. "Can't see the forest for the trees" syndrome, if you get my drift.

 

[pajo]

denso

I thought that everyone was using #25312179 heated but I guess not ..My last two attempts getting near 28 psi resulted in blown head gasket so I am back in the garage practicing head gasket replacement and I am glad because it could be much worse then that .:biggrin:

 

[bison]

Good grief! Finally somebody that has seen the same thing I've seen on every car I've looked at with a Denso in it!! I just quit trying to convince folks of how crappy they were for daily driving closed loop operation. Everytime I tried explaining it all I got was a lot of verbal abuse. All they can see is how well it does with leaded fuel. "Can't see the forest for the trees" syndrome, if you get my drift.

Yeah. I had great success with any of the 3 wire Bosch sensors but they couldnt handle more than a tank full of leaded before they got lazy. For unleaded/alky injeciton i wouldnt use anything but a Bosch for narrowband. The Denso actually do just as chitty with leaded fuel as others but dont throw throw the code till their totally shot. AC has an old part # that i cant remember anymore that was a lot more resistant than others for narrow band and was still cross counting really well. It was spec'd for our military gas powered trucks that were using the leaded fuel in the middle east. Maybe someone else has the #.

 

[yullose]

Well DANG... I learn something new every day.

The problem I have is... I'm using a TT wideband correction chip... which needs the WB sensor.

I never had any problems with my Denso 1-wire sensors... but then again, I didn't know any better... As long as they didn't throw a code, they were "good" to me.

So... with all that said...

What narrow band sensor and what wideband sensor do you guys recommend for C16 leaded race fuel ?

 

[turboc87gn]

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