MPH on Log doesn't match timeslip

[TLKSCHP]

Anyone have a discrepancy from what you show in the log versus what your 1/4 mile time slip shows?
Time Slip is showing 129 MPH at 11.45 but my max MPH in the log is 122 and that's after the 1/4 mile.
also my RPM's seem to be off at 122 in my log I'm at 6328 which should only be around 5600.
I went out with my GPS and driving it reads within .5 mph. Trans isn't slipping

Boosted 98 C5 Corvette with 02 PCM running COS
Yank PAS3400, 231/239 617/623 114
A&A kit Vortech V3 hitting 10psi
3.73 gears 27.2'" tall tires

checked with others logging at the track and they don't have any issues

Yes I'm aware of the injector duty, that doesn't add up either. 60lbs siemens

[joecar]

What laptop are you using (is it fast enough)...?

[TLKSCHP]

Samsung 1.8 AMD A8 6 gig ram win10

[joecar]

That should be sufficiently fast.

[joecar]

Maybe try to sanity check using landmarks separated by a known/verified distance...

check at 60, 80, 100, 120 mph (if you can).

[TLKSCHP]

I will give anything a try at this point. My rpm is killing me also. its set to shift at 6500 but doesn't until 7000. Originally had it at 6800 but was shifting at 7400 according to the log

[joecar]

I will give anything a try at this point. My rpm is killing me also. its set to shift at 6500 but doesn't until 7000. Originally had it at 6800 but was shifting at 7400 according to the log



Set the WOT MPH shiftpoint a lot lower, and then fine tune the WOT RPM shiftpoint (or vice-versa).

[TLKSCHP]

I have it about 20mph below now but someone else was telling me they had to go all the way to single digits

[joecar]

Post your tune file.

[TLKSCHP]

Post your tune file.

I added the tune and some more info about my car to the first post. Well i feel stupid, i double checked and my 20mph buffer wasn't that, it was allot closer. So i will get that adjusted and focus on why my rpm & mph seems off. If anyone wants look through the tune feel free, I'm new to boost and in way over my head with this tuning but all the shops around me Use HP and i like the efi live COS better so I'm on my own with no dyno.

Thanks again as always for the help and support
John

[TLKSCHP]

So I called A&A Corvette and talked with Josh and he said that's pretty common for the log MPH not to match the Time slip but time slip is the correct one. Most people probably never compare the two i guess. I've been lucky the engine hasn't popped running 16 deg of timing also, without meth he suggested 12 deg max. So alky control meth kit is getting ordered. As for the rpm being high, my research leads to Yanks rebuild being a little less efficient then my last one and 6% or more is common RPM fluctuation. So might have to change gears or figure out how to fit 28'' tire under the back.

So when running boost how do you determine what to much timing is?

I would like to add if anyone is looking at adding boost to a Corvette A&A has been great, always willing to talk through things and will work with you on trying to get you into a kit. helped me with the pcm swap, cam, gears, and everything involved when i had questions. Only negative is they tune with HP :(