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Discussion Starter · #1 ·
Picked up a slightly used SP58GT BK -install went well and everything was well made/thoughtout. I am having some problems now that its up and running. Specifically, its slower @ 21 psi than my BPU+ setup at 19psi.

Mods:
SP58GT BK
3" DP
Greddy PE Cat-Back
BCC
Fields SFC
Profec B Boost controller
K&N Cone

I have it tuned to 12.0 AFRs running 108 leaded. New 6097s @ .032 gap and just completed a boost leak check with no anomolies. I'm running the stock MAF and SMIC. Full tilt 21-22 psi is getting me 115mph traps whereas I saw 117 at BPU+ at 19psi. Car *feels* semi decent in 2nd but seems to lay down in 3rd (its an auto). Just feels like it's 50hp or so down of what it should be based on others #s.

Any ideas?
 

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earl3 said:
Picked up a slightly used SP58GT BK -install went well and everything was well made/thoughtout. I am having some problems now that its up and running. Specifically, its slower @ 21 psi than my BPU+ setup at 19psi.

Mods:
SP58GT BK
3" DP
Greddy PE Cat-Back
BCC
Fields SFC
Profec B Boost controller
K&N Cone

I have it tuned to 12.0 AFRs running 108 leaded. New 6097s @ .032 gap and just completed a boost leak check with no anomolies. I'm running the stock MAF and SMIC. Full tilt 21-22 psi is getting me 115mph traps whereas I saw 117 at BPU+ at 19psi. Car *feels* semi decent in 2nd but seems to lay down in 3rd (its an auto). Just feels like it's 50hp or so down of what it should be based on others #s.

Any ideas?
check ur tranny fluid...
 

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swearitsstock said:
check ur tranny fluid...
????

Could it be that because of the extra lag of the single turbo you are not getting good 60ft's and your mph also suffers? Or does the butt dyno also say you are down on power?
 

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by that i mean, make sure its not your trans thats slipping... additional power means additional stress on the trans... if your making less power (notably in 3rd gear) it sounds like your trans is on its way out

the 58 budget kit doesnt have more lag then stock twins, and it should be making more power... given that you did everything correctly (pressure test, no misfire, proper fuel) then my next suggestion is checking the transmission

sorry but i posted that earlier in a rush
 

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Discussion Starter · #5 ·
Thanks swearitsstock, trans fluid seems to be ok and the shifts are firm. The exhaust was banging pretty good on a heat shield stud -maybe getting some knock sensor activity? (long shot I know)

Krister, the 60's are pretty bad as expected (2.4), but its does 91 in the 1/8th and then 114-115 in the 1/4. I would think even a small single should charge a little harder in the 2nd half.

I'll run a comp check just to be sure.
 

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Get it on the dyno, sometimes your ass and traps can/will lie
 
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Get rid of the MAF by using VPC and it will be a different story. Single turbo with MAF plugging the intake tract is oxymoron
 

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Notorious 2JZ said:
Get rid of the MAF by using VPC and it will be a different story. Single turbo with MAF plugging the intake tract is oxymoron
I'd have to disagree. There has been test done on stock twin cars with and with out the maf netting very minimal gains if any gains at all. The thread starter is running a small turbo thats is not making the high hp that would benefit from the removal of the maf. Mohd made over 600whp with the stock maf in place. Im sure some extra ponies could have been picked up but my point is the maf is not as restrictive as it may seem.
 

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First off 12.0 A/F is too lean.
 

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Boost4fun
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Yeah ok, but at a marginal level. This shouldn´t influence the #`s not and if rather in the upper(upwards) direction, or?
Gerd
 

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it sounds like your transmission to me as well. You might just pass me off as an idiot, but in my MKIII i bought for $1k, the auto tranny was a piece of shit... and it would slip VERYYYY BADLY in 3rd gear and up if i was punching it. It shifted fast and the shifts wouldnt lead you to believe it was malfunctioning. it was when i took it on a lone stretch of highway, punched the gas and notice i was redlining really fast in every gear and not travelling very fast for redlining 5th.

then i made the connection: the trans is slipping.

have you noticed the stall speed of your torque converter (the rpm at which it begins to engage) slowly start to increase little by little?
 

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earl3 said:
Picked up a slightly used SP58GT BK -install went well and everything was well made/thoughtout. I am having some problems now that its up and running. Specifically, its slower @ 21 psi than my BPU+ setup at 19psi.

Mods:
SP58GT BK
3" DP
Greddy PE Cat-Back
BCC
Fields SFC
Profec B Boost controller
K&N Cone

I have it tuned to 12.0 AFRs running 108 leaded. New 6097s @ .032 gap and just completed a boost leak check with no anomolies. I'm running the stock MAF and SMIC. Full tilt 21-22 psi is getting me 115mph traps whereas I saw 117 at BPU+ at 19psi. Car *feels* semi decent in 2nd but seems to lay down in 3rd (its an auto). Just feels like it's 50hp or so down of what it should be based on others #s.

Any ideas?
Hmm...like someone stated above double check to ensure your tranny fluid is at the proper level. Would be nice to see some dyno numbers for number comparisons.....head out to the freeway and punch it from about 75 or 80 mph and see if you redline quick.
 

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Discussion Starter · #13 ·
davidX said:
First off 12.0 A/F is too lean.

On straight 108 leaded at 21-22 psi?


The engine does not free rev like a slipping tranny, just slower to pull through 3rd. I did throw a code today -I'm guessing its the charcoal canister purge since I capped it but maybe its something else.

Thanks everyone for the help so far!
 

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Kwan Jul Sul Freak
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Resetting the ECU doesnt help? With an auto tranny, pull ECU1 fuse and ECU2 fuse to reset everything. A Toyota tech at my local dealership to me this.

Is TRAC disabled? Not good for longevity of the tranny, but if you make a quick highway run with it disabled one time and it feels better, it might be the culprit.

Sounds like the tranny is gettin a little sloppy. Drain it, check the fluid. Drop the tranny pan and look for debris. Also, check the filter once the pan is dropped. Look for globs of black stuff (clutch material).
 

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natan said:
my MKIII i bought for $1k, the auto tranny was a piece of shit.............. it was when i took it on a lone stretch of highway, punched the gas and notice i was redlining really fast in every gear and not travelling very fast for redlining 5th.
You had a 5 speed auto in your mkIII?
 

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I'd say from experience that you are out of fuel. Did you check you AFR's all the way through 3rd? I know that when I had my SP58GT kit, and MAF I was limited to around 19psi due to the restriction of the MAF. I put a VPC on and my 19psi setting went to 25psi!! Woops!. But then I was out of fuel... If you are on stock fuel, put a pressure guage on it, I bet you are losing Fuel Pressure in 3rd gear, as the load gets greater... That's what mine was.
 

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Discussion Starter · #17 ·
InTheRed said:
I'd say from experience that you are out of fuel. Did you check you AFR's all the way through 3rd? I know that when I had my SP58GT kit, and MAF I was limited to around 19psi due to the restriction of the MAF. I put a VPC on and my 19psi setting went to 25psi!! Woops!. But then I was out of fuel... If you are on stock fuel, put a pressure guage on it, I bet you are losing Fuel Pressure in 3rd gear, as the load gets greater... That's what mine was.
I can get 24 psi with room to spare on the boost controller. AFRs look good through 3rd gear as well. I'll check out the pressure anyways though.

Pulled codes today:

P1511 Boost Pressure Low (Normal with a single)

P1630 Traction Control System Malfunction (Fuse is pulled but is this normal?)

Now that I have access to on OBD2 meter I'm going to log mass air, timing, and IAT and see if anything unusual is happening. Still no signs of tranny problems...fluid looks good, shifts firm, runs cool.
 

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Discussion Starter · #18 ·
Update:

Full boost (17-18 psi) is occuring at ~4600 rpm in 2nd gear (auto). This seems a bit late for the 58gt. Maybe I do have a boost leak somewhere.
 

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I am not super fimilar with the budget kit but my friend has a SP57 kit on his 94 auto. He is tunning using SAFC and VPC and had fuel problems on stock fuel at 15 PSI only putting down 450 RWHP on 110 Octane at 11.5-11.8 AFR.

His mods are
RMM DP
HKS TI
HKS FCD
HKS CAM GEARS
Profec B Spec 2 BC
SAFC
VPC

His problems were revealed on the dyno after the cam gear install. Previous to this he has ran 21 PSI on 110 because he assumed that he had enough fuel.

We just sourced everything for his fuel system and will install it soon, going to a PHR rail, Seimens 720 cc injectors and the Dampner Bypass. Hopefully the one Walbro will do the job in the tank.
 

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If your stock pump is the least bit weak, the problem will show up with the small single. It does flow significantly more than stock twins.
 
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