?'s about detonation.

big T

New Member
Feb 25, 2004
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Hawaii, oahu
Ive installed the hypertech tuning program set for 93 oct gas, but we only have 92 oct in HI, though I use oct boost with every fill-up. If the is a problem with detonation/pinging will it show up as a dtc(trouble code's) within the computer? I recently changed the shift points with the programmer, but it didnt detect any trouble codes in the process. The car doesnt ping often, and I would think that if there was a problem the programmer should tell me about it.
 
I am not sure if the OBD-II can detect pinging, but I don't think it does, and I would not count on it.

Since I live in California with only 91 octane fuel available, I contacted Hypertech to ask if 91 octane fuel would ping with their product. They said it probably would. So I selected the Diablo Predator, which allows timing adjustments in 0.5% increments.

But with 92 octane fuel, you might (and I emphasize might) be OK. Listen carefully for pinging. It sounds like marbles bouncing around in a steel coffee can.
 
It won't detect pinging but if something is really wrong with the car that may cause the pinging it will show.

Reasons why you car may ping:

1. Running lean, not enough fuel
2. Water in the tank.
3. Wires,coils, spark plugs
4. Timing
5. Crap fuel

It really doesn't matter if you only have 91 92 oct your fine. Now if your putting in 87 you may have a problem.

I'm not sure about your car but the 4vs you can't put nothing less than 92. I put 89 in my car onces and it didn't like it. The car started pingin.
 
big T said:
So by using the oct boost, is it helping raise the oct or waisting money?
It will offer a minimal improvement - maybe boost octane a maximum of 0.6 points for every bottle.

With my previous (highly modified) V-6 Stang, one particular chip pinged with ported and polished heads and manifolds and an aftermarket cam. I tried three bottles of NOS octane boost, and it still pinged.

So, IMHO, if you need to add octane boost, you have fundamental problems with tuning that should be addressed.
 
aloha brah

you on oahu? there is a sunoco on king st. in moiliili that sells 100 octane gas. next to da mcdonalds. but its 5 or 6 bux a gallon. so probably the same cost as the octane boost.

I recently installed a SCT chip from modular depot and begun to hear the lovely marbles rolling in a tin can sound of detonation at low rpms. especially with the vent or AC on, going up hill while undergeared. car sounded like absolute CRAP, i was about to send the chip back. I changed over 92 octane seems to have cured it but i tell ya this mail order tuning thing kinda has me worried. i didn't ask them to increase my timing, but i guess they think they are doing me a favor somehow. at least knowing what settings their chip are on would help but not even that. haven't even got a response from 3 questions i emailed those guys since SUNDAY. is there e-mail down or nobody reads it? ken? i'm about to call them.

anyways just to add, i've heard also that low coolant can cause detonation. my coolant lev was in the fill area. Certainly if you havent had a flush for longer than a year, you are probably due. My coolant was rust colored and there was a lot of sediment. I don't think I changed mine, perhaps once. Now my cooling systems all flushed and cleaned and refilled and I'm using redline water wetter which is supposed to reduce cylinder head temps too... so that should help.
 
big T said:
Ive installed the hypertech tuning program set for 93 oct gas, but we only have 92 oct in HI, though I use oct boost with every fill-up. If the is a problem with detonation/pinging will it show up as a dtc(trouble code's) within the computer? I recently changed the shift points with the programmer, but it didnt detect any trouble codes in the process. The car doesnt ping often, and I would think that if there was a problem the programmer should tell me about it.
Dont waste your time with octane boost the difference from 92-93 isnt that much to jutify the expense. Get some cooler spark plugs autolite 764's or aswf-22c's which are 1 heat range cooler than stock. Also put a 180 degree thermostat in it. If you get 92 make sure it is a quality fuel and not some run down crap station with the cheapest in town. Having the cooling system flushed is always a good idea. If that doesnt fix it get with your tuner and have them take a degree or two of timing out.
Just for referrence I have a headswapped 97GT and it is somewhere is around 10.5:1 compression. I run 91 most of the time and I had a little detonation with my tune so I put a cooler plug and the 180 stat in and since then we have seen some 100+ degree days and I have not had any detonation at all.