[laynlo15]

Just checking to see if anyone is moving up the shift points to a higher RPM when tuning after PTB and IM. Plus if you have long tubes as I do and having the better flow in and out of the LT1 is it beneficial. I was SC for almost 4 years on my SS just trying to figure out what you guys are doing NA. Obviously we are just talking no internal mods, just bolt on. Goal is to get into the 10s next time out.

[supersportss]

What valve springs are you running?

[6spdhyperblue]

Same shift points IMO

Maybe another 50 rpm on a auto, within error on a manual

[s346k]

same shift points. the ported stock intake didn't push the power out much, just up. my dyno basically showed the peak around 5800 and then it was immediately on the descent.

i must say, props to stewart's porting. i went from stock air box, tb and stock ported intake to rotofab, lt5 tb and unported msd...only picked up 15 whp peak. but damn, its pretty flat to 6800. 7k limiter now, gonna aim for 6800 shift.

those poor dod lifters.

[laynlo15]

No internal mods, stock springs. I think on my logs its shifting at 6275 or right about that. I'm used to with my Camaro shifting at 6800, but it was far from stock. I never really worry about what the dyno says. My car only made 15 more rwhp when I did the headers and xpipe and I retuned it.. However it ran 4/10s quicker and a bunch of 8 mph so I'm just putting it back on the dyno with the ported stuff and tune it again. If it makes more fine if it doesn't the track will tell the true story.

[s346k]

agree. dynos arent good for much. i put mine on the same one it was tuned on to see what the power curve looked like. trying to gauge a shiffpoibt on feel is tough

[6spdhyperblue]

I thought the autos shift earlier in the first gears

[laynlo15]

Mine isn't according to the tune. Its says 6400 but its shifting before that. I'll log it at the track next weekend again. But will dyno it again on Wednesday, I also have a 95MM Lt5 thats been ported but won't try that this week. I'll run the 87 ported when I race next weekend and the following we can get it back on the dyno with the 95mm.

[KingLT1]

These Automatics don't shift based off RPM, they shift based off of MPH. You need to raise the shift MPH points to hit the target RPM. You also do not want them shifting past the target RPM or you get odd shifts from my experience. So set the target RPM, then start changing the shift MPH till they are close to the RPM set point or just a hair short of. I also set first gear to shift earlier then the other gear just in case it spins, it won't over shoot and hit fuel cut. Pretty sure that is why GM sets them up that way to begin with.

[laynlo15]

You know I moved it back last time so really wondering if it worked. I'll look at it again.

[laynlo15]

35 60 87 114 157MPH all at 6400

[laynlo15]

It won't spin at all, last time out 1.63 to 1.68 on almost every pass, I think my worst 60ft was 1.70. I'm going to throw some more timing at it on the launch and keep adding a degree till its spins then back it off. Plus I'm still a little rich up top for an NA on E85. I'll lean the PE out till I get it to about 13.0 to 13.2, right now I'm 12.7 from above 4000 on up. I'm hell bent on getting in the 10s at 127 and 7.10 at over 100. Got just a couple more outings to make it happen.

[6spdhyperblue]

I’d say extend the 3-4 and 4-5 at least to 6500

[laynlo15]

6spd thats a pretty good idea.