how much boost with 91 and alky

[87gn/92ty]

I just got the new head gaskets in and it seems I am getting knock on only 17lbs with 91 and alky. What is the max boost I should be able to go with the mods in my sig and alky. I have heard 22-24 is not uncommon with pump gas and alky. Also could it be that my knock gauge is detecting false knock?? All help appreciated.

Mike

 

[Razor]

Timing, alky amount, and fueling play a major role in knock reduction. Any combination of those three.. you'r going to knock.

Do your tests in a gear, and watch for knock activity. Real knock will escalate.. not bammmm show up. Kind of like a ramp going up hill, not a spike.

 

[turbot2112]

got a scantool.whos alky kit you using. were are your o2s.

 

[87gn/92ty]

Not sure where 02's are, or what type of kit it is. I know I need to get a scan tool and check for actual knock and all that. I was just curious as I though 24lbs on alky would be no prob.

Mike

 

[Razor]

Well if your only spraying one ounce at 24 PSI your going to knock with alky. If your running 28 degree's timing and spraying very little.. your gonna knock. If your fuel pressure/O2's are dropping hard.. your going to knock. But as my previous post stated... too many variables..not enough real info from you.

Yes 24 PSI shouldnt be a problem with an alky system "dialed" in.

But you dont give enough data for "real" help to be given.

Its not a Mconalds drive thru.. takes a little thought process to make things happen on limited octane.




Mike,

You said, "Not sure where 02's are, or what type of kit it is. I know I need to get a scan tool and check for actual knock and all that."

No scan tool...you'll never figure it out. End of story. Keep the boost under 14 PSI unless you want to do HG's again.

Dont mean to be harsh, it is what it is.

 

[87gn/92ty]

I know I need to get it dialed in with a scan tool I just wanted to get an idea of what boost levels are common so when I am dialed in I know where I can safely go.

Thanks for the info as I getthis dialed in I am sure I will have more questionss but I just got the car and need to figure it all out.

Mike

 

[WHEEZER]

Mike, could be a rich knock,could be a lean knock, could be a timing knock blah blah blah....as Razor stated, you GOT to have a scantool. I'm "learning" these car's too. I popped a headgasket on a new GROOM's engine because of the same situation you're in. You CANNOT read a newspaper if you're blind, sorry for yelling.A baseline that's good for one car could be the opposite for another. As the most basic entry level scantool is scanmaster,that's what I bought. From Postons. Pony up guy and I hope this helps you.

 

[badboy86gn2]

87gn/92ty

BEING WERE YOUR AT (HIGH ELEVATION) AND CRAP FUEL YOU NEED TO RUN NO MORE THAN 19DEG TIMING IN 3RD AND 4TH TRUST ME I RAN 25PSI WITH CHEVERON GAS(ONLY ONE I TRUST HERE) ON PUMP GAS

Johnny

I will assure you will run faster with more boost and less timing then visa versa until you use high octane

 

[V8Killer]

I ran around for months w/a 25 degree timing chip @ 22-23 lbs of boost in third gear (no 2nd & 3rd timing drop). Pump gas w/no knock at all & this was in a TTA that supposedly doesn't do well with high timing.....I dunno