how much octane for 26* of timing

[84gnguy]

If you are running 16-17 lbs. of boost with 26* of timing ,what would be the suitable octane? I would guess 110,but I don't want to take a chance...

 

[Little6pack]

If you were running alky you could get away with 93.
but your right it can't hurt to have higher. We have an unleaded 104 at a local sunoco.

Just this past weekend I ran with 93 & alky at 21 lbs ZERO KNOCK

 

[8UWITH6]

27-28psi on 93 and alky here............. 26/24 timing

 

[84gnguy]

Guys,I can appreciate the alky info...but I still would like to know if 110 octane is what I need to run 26* of timing with 16-17 lbs. of boost.
This is just for occasional track use....combo listed in my signature.

 

[jasjamz]

Do you have a scan tool like a scanmaster or power logger?
If not you need one. How are you going to watch the 02s or knock?
110 should be enough if the tune is right for 17 psi and 26* Why not back the timing down to like 23/22 degrees and use more boost?

 

[bison]

98-100 octane. You would be better off with 20psi and 19*. Probably require a little less octane

 

[Razor]

The factory chips on the 86/87 where 26 degree's timing. Boost was set to 15 PSI.

The quagmire in this post is his screen name "84" Gnguy.. meaning he may own a "HOTAIR" and those things are an animal of their own.. unlike he 86/87 IC.

With a HOTAIR you guess.. a lot.. since you cant use a scanmaster like you can on the 86/87. But you can buy an audible or visual knock detector and make sure it doesnt go off.

 

[84gnguy]

The question I asked pertains to the 87 GN listed in my signature...not a hot air car.
Sorry if my user name and car don't match
I'll go with the 110 to be safe......it has run fine before with this chip and 110
Also the factory stock chip for 86/87 has 21 or 22* of timing IIRC

 

[Razor]

Ok. So who makes a chip designed to run 26 degree's and support fuel wise 16 PSI boost?

 

[84gnguy]

Ok. So who makes a chip designed to run 26 degree's and support fuel wise 16 PSI boost?

factory TTA chip
I confirmed the timing with Eric at TT
Here is an old thread I started:
http://www.turbobuick.com/forums/turbo-trans-am-tech/170691-question-about-tta-vs-gn.html

 

[RatFink]

110 never hurts.

 

[Razor]

factory TTA chip
I confirmed the timing with Eric at TT
Here is an old thread I started:
http://www.turbobuick.com/forums/turbo-trans-am-tech/170691-question-about-tta-vs-gn.html

Like I said 4 years ago. Why would you run a TTA chip and old technology when the TT chip will flat out be better. Allow higher boost, idle better, have better manners, etc.

My TTA would run 16 PSI with the factory chip no problems. TTA chip has lower timing than GN. Thats why it allows higher boost with same octane. Compression is same on both motors.. so the heads deal is crap.

TTA also runs a 237 reg vs the GN runs a 233. So you need to run higher FP for the TTA chip.

Knowing what I know today.. I would not run a stock chip. Unless i'm selling the car as original.

 

[Razor]

I'll dig up the .bins and see whats the deal if i get some time.

I still think it was lower.

 

[84gnguy]

TTA chip has lower timing than GN.

that is not correct...and you did admit to that in the other thread from 4 years ago..the TTA chip does indeed have 26*

your quote from the other thread:

I stand corrected..it does have 26 degree's past 4400 RPM's at load values over 192.

I'll dig up the .bins and see whats the deal if i get some time.

I still think it was lower.

the .bins are listed in the other thread from 4 years ago...

this is nothing more than an experiment at the track...install the TTA chip,bolt on the Hoosier QT DOT pros,turn up the fuel pressure and dump some 110 octane in the tank.Leave the rest alone.
I just wanted to make sure the 110 is what I need to be safe..that is all I am asking.