Jetting for 08 summit

[King]

I had my ecm sent out and re-programmed last year and when it came back it doesn't seem to get the revs when I'm pulling hills. I have installed a DJ clutch kit but left stock ramps. 17.2 gram wieghts that came with kit. I have to run on clicker 5 to get 8000rpm at 6000ft. I have heard other people say if you send your ecm out to get re-maped by RKt (which mine was, by Specialty Sleds), then you have to run 480 to 490 jets. the re-map advances your timming and it needs more fuel at the top end. Any suggestions, besides the obvious, try the 490's and see. Oh ya I am also getting Split Seconds 860 kit put on as we speak.

 

[magnet]

I had my ecm sent out and re-programmed last year and when it came back it doesn't seem to get the revs when I'm pulling hills. I have installed a DJ clutch kit but left stock ramps. 17.2 gram wieghts that came with kit. I have to run on clicker 5 to get 8000rpm at 6000ft. I have heard other people say if you send your ecm out to get re-maped by RKt (which mine was, by Specialty Sleds), then you have to run 480 to 490 jets. the re-map advances your timming and it needs more fuel at the top end. Any suggestions, besides the obvious, try the 490's and see. Oh ya I am also getting Split Seconds 860 kit put on as we speak.

i would say wait till all mods are done then start messin.

 

[takethebounce]

Without looking at the calibration sheet, 17.2 sounds high. Should be down between 15-16 g. I believe 1 g = about 200 rpm. Which if you went to 16.2 you would increase your rpm's to 8200 on clicker 5, went to 15.3, you would get the 8200 on clicker 4, which is where you want to be. Are you running stock gearing?

As far as questions concerning the ECM program, give Kelsey a call at RK-tek and he can answer your jetting questions for his tune.

But as mentioned, you are going to have to start fresh again anyhow after you get the 860 overbore done.

I don't know much about the Split Seconds 860, but if they have tested and proved their product, they should be able to give you a base line of where to start.

 

[Modman]

I had my ecm sent out and re-programmed last year and when it came back it doesn't seem to get the revs when I'm pulling hills. I have installed a DJ clutch kit but left stock ramps. 17.2 gram wieghts that came with kit. I have to run on clicker 5 to get 8000rpm at 6000ft. I have heard other people say if you send your ecm out to get re-maped by RKt (which mine was, by Specialty Sleds), then you have to run 480 to 490 jets. the re-map advances your timming and it needs more fuel at the top end. Any suggestions, besides the obvious, try the 490's and see. Oh ya I am also getting Split Seconds 860 kit put on as we speak.

17.2 is probably too heavy for your motor, which is why you aren't pulling the RPM.

Always jet by what the plugs look like.

As indicated though, you're going to have to start over once your big bore comes back. Talk to DaveB, he can give you some pointers on how to clutch that big bore.

 

[DaveB]

The best gain you will see is to lose the stock 413 ramps and get into DJ's mountain ramp....which is a blend of the 413 and the 441 (2009 ramp). The weight you have in there is on par for the 413 ramp(very thick at the top)....but clicker 5 seems out of line....you're not making the power.

 

[King]

Thanks guys

 

[duck]

Simple solution..... 15.8 grams pin weight and Joeys mountain ramps. I'm on setting 4 or 5 in the mountains and 2-3 back here on the prairies. Its an awesome set-up. No one else is even close!