I need help!

[1toofastlt1]

I put this blower on and i do everything myself so i thought i would tune it myself. Im using Jet DST. is anyone else using that? I have the tune close but i dont think its quik right. i might have too much timing. IDK. can someone give me the run down on tuning for a supercharger or does someone have a tune i can see that have close to the same set up as me? im running a FMU with about 4-5 lbs of boost. and the mods in my sig.
Thanks Guys

[Fire67]

Get rid of the FMU first.. Its going to cause some tuning headaches with it inaccuracy. Get a simple bolt-on adjustable regulator, 42 lb-hr injectors, and a walbro 255lph high pressure pump if you dont already have one.

Then tune the base fuel and spark tables... As a hint, handle fueling with the PE table for anything above where the MAF maxes out.

Only thing that anyone should tell you about timing is this:
1) Its going to vary vehicle to vehicle and setup to setup, even identical setups.
2) Only real way to tune timing is on a dyno. If you tune using knock sensors on the street, your timing will be well passed the point were the most power is made. Let alone dangerously close to causing knock.

Only exception to #2 is a good track tune, because if you can drive consistantly, you will see differences in performance with your timeslips.

[Fastbird]

Get rid of the FMU first.. Its going to cause some tuning headaches with it inaccuracy. Get a simple bolt-on adjustable regulator, 42 lb-hr injectors, and a walbro 255lph high pressure pump if you dont already have one.

100% agree with the above.


2) Only real way to tune timing is on a dyno. If you tune using knock sensors on the street, your timing will be well passed the point were the most power is made. Let alone dangerously close to causing knock.

Only exception to #2 is a good track tune, because if you can drive consistantly, you will see differences in performance with your timeslips.

I have to disagree with the primary point of #2. You want the car to be tuned under the load it's going to see, and that means tuning it moving under it's own power, completely tuning it. THEN put it on the rollers. Reason I say that is your typically used dyno is a Dynojet 248C which utilizes a 3000lb drum. Problem is that these cars are heavier than 3000 lbs. What you end up with is a tune set for moving a 3000lb drum that's trying to move a 3400-3600 lb car. This will affect the major aspects of the tune, being timing, fueling, and your actual AFR. Tune it on the street, get your numbers off of the dyno.

This is null and void if you're on a Mustang or a Dyno Dynamics dyno, as those can be loaded up to reflect the weight and wind resistance/surface frontal area of the car.

[1toofastlt1]

do any of you guys using tunercats or jet dst have a tune i can use?

[BLOWNDFIZ]

FWIW, it has been said and documented many times on other forums that LT1's tend to perform the best around 26 degrees with a boosted set-up. That being said I would recommend you start more conservative on timing and work your way up to around 26 degrees.

My car with 9 psi on the dyno made the most power with 26 degrees. I am now running ~15 and I removed an additional .5 degree per lb/boost. Need to put it back on the dyno and add timing back slowly.

My recommendation is do a search on a few other boards. Not that I don't want to help, but there have been exhaustive threads covering timing on boosted LT1's. You can gain a ton of applicapable knowledge.

PM me if you want me to tell you the other forum, you probably have a good idea and a hint there is no LS in the forum name.

[MoeHorsePower]

Well there's a lot involved to a statement of run X amount of timing, Factors that take into play, Compression, Cam overlap, Head Flow, Head Chamber ect...

[1toofastlt1]

my engine is 100% stock