I set my timing to 8* and my car pink a lot. When the temp reach 220 deg, the motor pink almost all the time!! I see on this board someone with 10*. How can it be possible?

I bought gm Cleens and i would like to know if my problem can be the deposit of carbon?? or the timing chain?? (97000km)

thanks

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trans-am 91 3.08 posi 5.0 lb9 5 speed stock

 

Ok let me get this straight, you're running extra advanced timing with low octane gas, and you're wondering why you're getting pinGing?
...ed

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Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

so, can you say me how much octane i need with 8* or 10*??

With stock timing, 87 or 91 octane?



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trans-am 91 3.08 posi 5.0 lb9 5 speed stock

 

I put 92 octane in my car all the time .i have stock timing.It is not good for the car to keep switching octane when you find a good octane rating stay with it.unless you need more because of engine mods

 

If my car EVER gets up to 220 degrees it pings no matter what my timing is set at!! If I retard it enough to make it stop then it runs like crap!! I just threw in a 160 degree thermostat and now my car runs around 170-175 all the time and I can set my timing properly w/out pinging!! If you're running a 195 thermostat right now you might wanna try the 180 thermostat before going to the 160!!!

 

I would try some higher octane fuel. I use 92 in mine and I have no problems with it. I have used 87 before and it was a noticable change between the two. You might try running it through a few times.

Matt

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irocet@hotmail.com

drive.to/Stang_Kilr

88 IROC-Z -- 350 L-98, 700R4, Flowmaster, K&N, MAF Sceens Removed, Airfoil, March Pullies, Comp Cams Magnum 1.6 Roller Rockers, Bosch Platinum Plugs, Accel 8.8 mm Wires, Hypertech Cap & Coil, Hypertech Chip, Hotchkis Strut Tower Brace, One Loud Stereo!

 

87 Octane with 8 deg timing and high temp? No-no.

Higher temperatures make a motor ping
Lower octane makes a motor ping
Over-advanced timing makes a motor ping
All three makes a motor REALLY PING!

All the 'ping' is is severe detonation. Not good. Keep in mind SB Chevy's are very sensitive to timing. When the ECM picks up detonation, it retards timing (to a point). Keep it at stock, the ECM will do it's job. I dont recommend disconnecting the knock sensor unless you are absolutely certain it won't detonate. Frankly, 87 octane is crap. I wouldn't use it in my lawnmower. I won't use anything less than 93. Never had a problem. Run high-octane gas around 93, use a 180 degree thermostat and lower timing to stock, your pinging will be over. If not, the motor will be over.

How healthy is you ENTIRE ignition system?

 

This is what I use. I tried Advancing my Timing at 10 and 8 degrees and it pinged. I didn't think it should have but it did.

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'87 Trans Am:
(Engine)
305 TPI
180 Degree Thermostat
JET Fan Switch
TB Bypass
Accel 300+ 8.8 Racing Wires
Accel Super Coil
Bosch Platinium Plugs
Custom Ram Air with K&N
Removed Emissions Equipment & Cat.
(Stereo)
Full Kenwood Excelon System

 

Yeah, some higher octane should do it.

 

Just for general info, you should run your car on the lowest octane gas that it will run without getting detonation. That gives the most power with the least emissions. Running two high of an octane leaves excess unburnt fuel, less power, higher emissions.

 

OK. I am running my car at 12 deg. My car doesn't ping and I am using 92 pump gas. I have a chip that advances even more. I think you should check the slack in your timing chain by moving your crank back and forth while watching your rotor. But I really think it is carbon deposits. That raises your compression which causes pinging and it get red hot which will ignite the fuel before the plug sparks. Try some top engine cleaner. trav

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1987 Camaro Iroc-Z Z-28 with a TPI 5.7
-Ram Air,K&N Filterchargers, Gutted Mass
Airflow Sensor, Throttle Body Airfoil,
Edelbrock TES Headers and Y pipe, Gutted
Cat, 3 inch exhaust, Flowmaster
-Hypertech Thermomaster Chip, 160 deg Stat,
Adjustable Fuel Pressure Regulator
set at 50 psi, MSD Cap, MSD 8.5mm wires,
Accel Coil, MSD 6AL Ignition Box, Accel
Plugs
-Richmond 3.73 Gears, B&M Transpak,
B&M Rachet Shifter, Energy Suspension
Products
-Fiberglass Cowl Induction Hood,
Purple Neon License Plate Frame,
16X8 Rims with BFG 245 50's,
Pioneer Deck, 2 JL 12's in a Q-Logic
Box with a 300 Watt amp

What you can put between your ears,
no one can take away.

 

I would look for vacuum leaks, and make sure that you are setting the timing correctly and that the mark is right on the balancer. Balancers dont last forever, if its wobbling or the outer ring has moved towards the engine, its bad and your timing probably isnt at 8 but somewhere else.
Right now I'm running 10 on a stock 91 engine and I run 87 octane all the time. Doesnt ever ping.

 

I'm telling you it's the temperature!! I run 90 and 91 octane in my car all the time and it never pings!! I can't say where my timing is at because I have an '89 balancer in my '86 TA and the timing marks are off but I just run my timing up, rev the car to check for pinging, once it pings at a certain timing I back it off just a bit and it works fine for me!!

It's partially a HEAT problem for you! Drop your temp down to about 180-190 and I'll bet that'll make a difference for ya!!

 

I just run 93, since I live in FL I don't have to worry about emissions . A healthy ignition helps here, especially with an MSD. Unburnt fuel can also be a result of inproper timing, too. I never worried about spark scatter or a worn chain since I replaced mine with a double roller a week after I got the car. I also like 93 just because it keeps the engine (somewhat) clean.

 

You are 100% right about the damper. Mine had slipped big time (towards the engine) and I had to tune my engine by ear. Found out it was at 16* as soon as I put a new StreetDamper.



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'88 GTA 350 Full of Leprosy (rust)
Full Exhaust, Free mods, Xtreme Energy cam, Intake Pieces and 2100 RPM TQ

13.39@102.50 MPH
1.90 Sec ----- Best 60FT
104.23 MPH -- Best Trap Speed
AIM HIGH!