TT 93 Street Tune Lean

GNChanto

New Member
So Just want to see some thoughts of users here,
Currently just picked up a Turbo Tweak Tune 93 Street 19/17 15-17 psi. Eric stated his tune the maf needs to lock onto 255 to have proper fueling.
Car has usual mods, TA-49, Exhaust, K&N Intake, FPR, Racetronix 255 Pump and some other parts not as important

The boost is set to about 15 psi and the Maf reading reads 220- 236 during the pull and it seems like the Maf readings take forever to come up like 236 is max WOT high rpm during this pass I see super Lean O2 values like 710-735. I also believe the ramp up is super lean too, backfired on me once at like 2psi, 5KR and I think low o2 values (I'm thinking cause lean but I was more worried about lifting than looking at the o2 values)

When I added 15% more fuel values jumped up to like 740-760 o2 and I don't see any KR but still feels like its running super lean and seems to fall lean on the spool up still.

Eric stated to me that the tune wont run right if the MAF isnt locking onto 255, Which it currently isn't so I'm thinking the Maf is kind of lazy and low on the calibration. To remedy this problem, should I just get a maf translator with a LT1 3" maf ? Slightly bump up the WOT setting on the translator if the LT1 sensor isn't hitting 255 so it hits 255 every time.

Idle Values
These are my numbers at Idle after a 20 minute drive.
AF -04
L8 - 30-31
Bat -13.7
INT - 128
BL - 135
CLE -166-170
ATS - 131 (I know its hot was idling for a few minutes sitting while I was writing down numbers)
R - 800
TPS - .38 WOT Verified to be Locked to 4.70 (Caspers TPS throttle enhancer)
Iac - 15

Car worked just fine on my (96) octane PTE tune 20 degrees timing at 18-19 psi, O2 values 800-815 so I am assuming this chip is locking to 255 cause it should be wayy past locking out the maf.

Any thoughts on the future and how I can get MAF readings to lock to 255 on 15-16 psi ? Maf Translator & LT1 maf?
 

SCOOBY DOO

I'M NOT A MONSTER, I'M JUST AHEAD OF THE CURVE!!!
Stock MAF's crap out on a regular basis. Go with a Translator and a LT1 MAF. Your BLM's are high so it's lean. Swap in a new Denso 02 sensor while you're at it. If you've been honest with the info you've given Eric, then his chip will be bang on on the default settings. Get rid of the throttle enhancer.
 

GNChanto

New Member
Any reason why to get rid of the throttle enhancer ? It does not activate until 70% throttle I guess I don't necessarily see it as a bad mod to have on the car? Can you give me more information about the drawbacks of having one ? I did tell Eric I had one when I placed the order for the tune.

My plan was to pickup the translator and lt1 MAF, do those just drop in ? I have a stock intake tube and a large K&N. Also how common is it for the o2 sensors to go bad I heard they go bad a lot but it seemed like the one I had read correctly.

Also I never built this car my dad did back in the 90s before I was born and he isn't around anymore to ask questions too so that's why I don't know all the reasons why certain mods were done.
 

SCOOBY DOO

I'M NOT A MONSTER, I'M JUST AHEAD OF THE CURVE!!!
The 02 sensor tells the ECM how to set the fueling. Junk in equals junk out.
 

Dylan4570

Member
the MAF sensor is one of the most noticeable drivability and reliability mods you can make to a stock ish GN in my opinion. It is night and day. significantly reduces the turbo lag.

on the stock turbo with a LT1 MAF the car sounds like a powerstroke pulling a landscaping trailer, its just always ready to spool up.

Another good idea is a wide-band 02 sensor. Makes it much easier for me to tune and monitor the AFR.
 

GNChanto

New Member
So update on the MAF, I installed the MAF today.
Completely changed the car night and day, The car now runs 15 psi boost & 0KR at WOT with WOT fueling set to 128 and the translator to the 0% WOT and set for the LT1 3" Maf. Its like I am driving a different car now spool up feels quick and pulled pretty damn good even with the DA like 2500 & the temperature being 95 degrees and 65% humidity

Inspected intake tube did not see any holes but I really don't like it, seems so flimsy for a intake tube I want to get a stainless tube & a cold air intake.

Data from today - Didn't get all the numbers cause at the end of the day when I was gonna check numbers the waterpump let go and started leaking.
WOT 02 numbers 830 -825 in 1st & 2nd , in 3rd the numbers dropped into high 700s like 795 so much better o2 values.

Idle #'s
BLM 118-119 Idle (Seems Rich Could be due to weather or I need to set the maf translator to LT1 (Richer Setting)
INT - 128
ATS - 115-120 degrees, Sensor inside of K&N filter max I saw was 125
Coolant - 175-180

Only bad thing that happened today was every like 3 or 4 times I was at partial throttle at like 5-10 psi of boost I sometimes would get about 2 degrees of KR could this be from the heat or maybe due to something else ? I cant directly replicate this every time it seems intermittent. I know these cars don't particularly like to be at partial throttle but I haven't ever seen this car have partial throttle Knock numbers before. Wouldn't save to the scan master though cause they were under a certain TPS number. Any thoughts on this ? is it bad or not real knock ?
 

Chuck Leeper

8/10's of a century!
Staff member
Inspected intake tube did not see any holes but I really don't like it, seems so flimsy for a intake tube I want to get a stainless tube & a cold air intake.
A good idea.
I have a long LED work lite I check with.
Run it inside and turn out the shop lites.
Look like a sieve?
Then I throw it away and goto one of Earl B's' intake pipes.
 

SCOOBY DOO

I'M NOT A MONSTER, I'M JUST AHEAD OF THE CURVE!!!
BLM's are fine...leave it alone. KR could be at a shift point...something hitting setting it off. Look for the downpipe hitting the frame, worn engine mounts, trans mount. Eric errs on the side of rich so we don't blow shit up.
 
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