95mm TB dyno & track results

what timing do you run on the street. the highest I ever ran on my car was 18 on street and 21 at the track with race gas... maybe why I never run anything good. im a big whimp!
 
Ever since the beginning of the whole "DIY" tuning process which I have supported but with reservations, I have been very concerned about the sharing of information between people. Not that sharing in and of itself is bad, but rather that sharing with the "well, it worked for me" concept is extremely dangerous, particularly as it relates to ignition timing.

Incorrect ignition timing is absolutely, hands down the #1 cause of all SC engine failures, and following the lead of what other people have done or think they have done is the root cause of an overwhelming majority of ignition timing related engine failures.

In any engine tuning process fuel delivery is priority #1 and setting ideal ignition timing is the final step that brings it all together. No two SC engine combinations are the same, and no single formula works for all or even a majority. It is therefore my recommendation that timing be kept very conservative until the last step of the tuning process which, to be effective, MUST be carried out via dyno AND track testing. No tune is complete until both have been completed successfully.



Cliffs: Don't fvck with your ignition timing unless you know what you are doing and are prepared to accept the possible consequences of your actions.
 
whooooooooooah. was just making convo my cars in a million pieces I didnt plan on going out and testing theorys out. and anyways, if I want good timing advice I can call casey ! HAHA
 
what timing do you run on the street. the highest I ever ran on my car was 18 on street and 21 at the track with race gas... maybe why I never run anything good. im a big whimp!

My particular combo likes/tolerates a lot of timing and was set for around 22 degrees at 3000 and gradually increasing to a max of 28 degrees at 6500 rpms. When racing the car I add about 3 gallons of C16 to a half tank of 93 octane.

I was running the same amount timing on the street using only the meth injection (75% methanol 25% water) and 93 octane gas. I don't put nearly as much load on the motor when driving it on the street because I'm only into the throttle hard for a second or two and the tires are always spinning when I do. Dyno adds a little more load, but again I'm only into the throttle hard for one gear from around 3100 till around 6600 rpms and that only last for a few seconds.

Reducing the WOT timing a couple degrees for street use is just me playing it safe, incase my meth injection system doesn't come on or I'm forced to used 91 octane. Tune also has a pretty agressive reduction in timing, if air charge temps exceed 140 degrees...so that covers me for meth injection failure or driving it hard in the summer.

David
 
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David, did you ever dyno test your tune with the C16 mixture? Do you have any of the factory timing retard options still functional?
 
My particular combo likes/tolerates a lot of timing and was set for around 22 degrees at 3000 and gradually increasing to a max of 28 degrees at 6500 rpms. When racing the car I add about 3 gallons of C16 to a half tank of 93 octane.

I was running the same amount timing on the street using only the meth injection (75% methanol 25% water) and 93 octane gas. I don't put nearly as much load on the motor when driving it on the street because I'm only into the throttle hard for a second or two and the tires are always spinning when I do. Dyno adds a little more load, but again I'm only into the throttle hard for one gear from around 3100 till around 6600 rpms and that only last for a few seconds.

Reducing the WOT timing a couple degrees for street use is just me playing it safe, incase my meth injection system doesn't come on or I'm forced to used 91 octane. Tune also has a pretty agressive reduction in timing, if air charge temps exceed 140 degrees...so that covers me for meth injection failure or driving it hard in the summer.

David

Just for giggles what is timing on your TURBO car? Or should I just call Dan?! :D
 
David, did you ever dyno test your tune with the C16 mixture? Do you have any of the factory timing retard options still functional?

No, I don't recall ever dyno tuning this car with C16 or other race fuels. Yes all the timing retard options except for the knock sensor are still functional.

David
 
Just for giggles what is timing on your TURBO car? Or should I just call Dan?! :D

Max is 20 degrees for street (93 octane, meth injection, 17 pounds of boost) and 23 degrees for race tune (straight C16, no meth, 23-24 pounds of boost). I'm told the C16 race tune timing could be set a lot higher, but I'm being conservative.

David
 
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Explained perfect DD, thats what I used the dyno during the shootout to set. Moved it up gradually till gain was minimal then backed it off to the previous.
 
Didn't mean to preach. :eek: I've seen some SC's that detonate badly at 22 deg. Compression ratio, cylinder head porting, camshaft profile, exhaust design, connecting rod ratio, cooling system and so on all affect octane sensitivity. David's engine was designed for maximum boost/octane tolerance and his tune reflects that.
 
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