Need Help with a Friends Cobalt SS/TC (LDK , Turbo Swap)
Hey guys,
I'm not usually one to ask for help however I need some, I have a friend that is moving across the country in a few days and due to shipping issues we just got his car back on the road with an LDK vs the stock LNF he blew up 2 years ago (long long story). After getting the car fired up last night I offered to read entire just to see if i saw anything "odd" in the tune (tuned from a local shop around the area), what i found was pretty shocking for me, even with little experience. It's basically a stock GMS1 tune with the PE table enriched up to .83 in the top end and as far as I can tell mostly just GMS1 other than some minor torque limit settings, and an "attempt" at MAF tuning, I'm at work now and working from memory of what I saw after a few beers last night.
Basically he needs to get this car moving safely by the end of the weekend (not optimally, safely, until he can get re tuned at the other end of his trip)
I'm waiting on him for an accurate mods list however I can start off with what I know / what I'm thinking.
LDK Swap from ZZP
KY Stage 3 Clutch
Tread Stone Stage 4 Turbo Kit (waiting on turbo model that he used), Filter on the turbo no intake tube.
Tread Stone Charge Pipes with HKS BOV and MAF Relocation (BOV is Before the MAF pretty sure thats the correct orientation)
Tread Stone TR10 Intercooler
3" CIA Catback with catless DP (yes i realize the cat warm up cycle is still on , i think COT is likely still on too , need to check this )
So I dont know that much so take this with a grain of salt.. I think he is slightly too rich at .83 .. seems like big turbos should be around .85 or 12.5 or so AFR(?)
Cat warm up needs to get turned off and idle RPM slightly increased,
Adjust MAF properly (is there anything different about tuning for a relocated maf/BOV i should be aware of or is it basically the same process as with intake maf tuning as long as BOV is located in the "right" place? )
DALs should be adjusted I'd say along with Wastegate for the new bigger turbo, help is really appreciated with suggestions here as I suspect this is likely the "magic" that makes a big turbo happy on our cars
Timing is Stock GMS1, i've seen some good come from simply smoothing this table on an otherwise stock car to "start" and get rid of some of the GMS1 knock but not sure if there are other "easy" wins to be had here, or if that logic even applies any more.
sorry for the pile of questions this is just slightly overwhelming on a short time line I know most people have weeks to tinker with settings especially after a new engine or a turbo swap so any help you guys can lend would be most appreciated!! (im not a professional tuner by any means nor do i claim to be just a dude with HPT that is looking to help out a friend)
I'll get a log file after work today as well i've just got the read all for now.
Thanks so much in advance!
Last edited by Whitmore29; 06-26-2015 at 08:20 AM.
Don't know how much boost you plan on running. But you target PE Lambda maximum should be around .88 or .87. But setup STFT+LTFT in the Histogram on scanner to log for dialing in the MAF Calibration table. Monitor knock retard and adjust timing table accordingly. But to raise boost pressure, yes you will need to increase your DALs. But I would focus on getting the MAF dialed in for him to be able to make his trip safely.
why does everyone ALWAYS INSIST on increasing DALs to increase boost pressure. I'm running 22 psi boost on the the GMPP stage DAL table. Fine, at redline it falls to somewhere between 20 to 21 psi, but "desired boost" is still high, i just don't have my wastegate duty cycle as high as everyone else. How much boost are you guys trying to reach that you need to increase DAL? Am i missing something here?
Well it depends on what you want to go for. Alot of peope shot for higher boost pressure. I would say a average around 24-25psi. But a lot of my customers do some motor work, so we go up to 28-30psi.
Don't increase it if you don't want more boost. Plain and simple. You aren't trying to make power right now, you are looking to make your friends car safe to drive. Let somebody that is experience tune it when he wants to get power out of it.
Thanks for the replies, I was able to get a data log in of his car and it wasn't pretty .. that said it wasn't horrendous either. I've seen GMS1 cars with Intakes with "as bad" of fuel trims, he had a little knock (again I've seen GMS1 stock cars as bad) but fuel pressure stayed consistent which is good to see. I couldn't convince him to float me the 1 credit's worth of money to get him licensed (~50 USD, no other fees at all, friends rate) so hes on his way without any kind of adjustment ... trims were rich about 8% or so and he still has his .83 PE.
, i think COT is likely still on too , need to check this )
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