Trick flow install underway
Drifting
Joined: Jul 2009
Posts: 1,319
Likes: 64
From: Lakeville, MA
St. Jude Donor '10
The moment of truth is SPIN is correct as usual. I did however get the Manifold to seal and it went nicely after making some clearance for the Head Washers. I still get the same cel's from 14 to 20 and the MAF is
around 8. Having said that I'm convinced I do not have a leak and the
fact of the matter is I changed the air flow dynamics by simply going
from the 92 to the 102 and they are considerably different internally not
just the 10mm larger opening. In short I need A tune and was looking at
Spins threads concerning MAF TABLE and to get it calibrated correctly
to get those LTFT's around zero. I need to learn a little more about HP TUNERS other than installing tunes and adding patches. I could appreciate some advice on that MAF TABLE for starters as I will be going to A 100MM MAF and 100 MM Throttle body. The ported 90 mm TB got some thick internals and at these power levels represents a restriction.
around 8. Having said that I'm convinced I do not have a leak and the
fact of the matter is I changed the air flow dynamics by simply going
from the 92 to the 102 and they are considerably different internally not
just the 10mm larger opening. In short I need A tune and was looking at
Spins threads concerning MAF TABLE and to get it calibrated correctly
to get those LTFT's around zero. I need to learn a little more about HP TUNERS other than installing tunes and adding patches. I could appreciate some advice on that MAF TABLE for starters as I will be going to A 100MM MAF and 100 MM Throttle body. The ported 90 mm TB got some thick internals and at these power levels represents a restriction.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
with the washers torquing it down felt good as I did it in steps. Before
when I was torquing it sounded like a gun going off because it was kind of hung up on the washers and then I guess it let go all at once. It was probably all right after that little episode but still had the high LTFT's
which led me to believe I may have cracked it. All is ok but the CEL trip
point for lean conditions proportionately on both banks after being advised
by SPIN I need A tune. Must start there.
Drifting
Joined: Jan 2010
Posts: 1,447
Likes: 1
From: Katy TX
The moment of truth is SPIN is correct as usual. I did however get the Manifold to seal and it went nicely after making some clearance for the Head Washers. I still get the same cel's from 14 to 20 and the MAF is
around 8. Having said that I'm convinced I do not have a leak and the
fact of the matter is I changed the air flow dynamics by simply going
from the 92 to the 102 and they are considerably different internally not
just the 10mm larger opening. In short I need A tune and was looking at
Spins threads concerning MAF TABLE and to get it calibrated correctly
to get those LTFT's around zero. I need to learn a little more about HP TUNERS other than installing tunes and adding patches. I could appreciate some advice on that MAF TABLE for starters as I will be going to A 100MM MAF and 100 MM Throttle body. The ported 90 mm TB got some thick internals and at these power levels represents a restriction.
around 8. Having said that I'm convinced I do not have a leak and the
fact of the matter is I changed the air flow dynamics by simply going
from the 92 to the 102 and they are considerably different internally not
just the 10mm larger opening. In short I need A tune and was looking at
Spins threads concerning MAF TABLE and to get it calibrated correctly
to get those LTFT's around zero. I need to learn a little more about HP TUNERS other than installing tunes and adding patches. I could appreciate some advice on that MAF TABLE for starters as I will be going to A 100MM MAF and 100 MM Throttle body. The ported 90 mm TB got some thick internals and at these power levels represents a restriction.
Last edited by All_Motor_C5LS6; May 12, 2010 at 12:33 PM.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
heads will never get you to 500 as they become A restriction around the 450 MARK. A big and bigger cam wont help. Trick flows will flow well on the ls2 even with smaller cams like mine. Spin points out as well as tony at AFR the 90 mm MAF becomes a restriction around 500. Those getting to 525 are running 100 mm MAFS and Im talking about the ls2 world.
I did some scans this morning with HP TUNERS and the LTFT's are consistently around 24 occasionally triping the CEL. I made some changes to the air flow table and I should see them come down. All
these nonsensical things are preventing me from evaluating the 102 against the 92 from many different perspectives.
Drifting
Joined: Jan 2010
Posts: 1,447
Likes: 1
From: Katy TX
I tend to agree on the TB. Anyone going north of 450 RWHP will find different things will have to be changed. For example the Stock 243
heads will never get you to 500 as they become A restriction around the 450 MARK. A big and bigger cam wont help. Trick flows will flow well on the ls2 even with smaller cams like mine. Spin points out as well as tony at AFR the 90 mm MAF becomes a restriction around 500. Those getting to 525 are running 100 mm MAFS and Im talking about the ls2 world.
I did some scans this morning with HP TUNERS and the LTFT's are consistently around 24 occasionally triping the CEL. I made some changes to the air flow table and I should see them come down. All
these nonsensical things are preventing me from evaluating the 102 against the 92 from many different perspectives.
heads will never get you to 500 as they become A restriction around the 450 MARK. A big and bigger cam wont help. Trick flows will flow well on the ls2 even with smaller cams like mine. Spin points out as well as tony at AFR the 90 mm MAF becomes a restriction around 500. Those getting to 525 are running 100 mm MAFS and Im talking about the ls2 world.
I did some scans this morning with HP TUNERS and the LTFT's are consistently around 24 occasionally triping the CEL. I made some changes to the air flow table and I should see them come down. All
these nonsensical things are preventing me from evaluating the 102 against the 92 from many different perspectives.
Last edited by All_Motor_C5LS6; May 12, 2010 at 02:50 PM.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
Adjust table and no changes.
I thought for sure installing a different table would lower those trims. 24.2
almost seems like it gets stuck there when crusin at 50 or accelerating. Im
beginning to think there is something wrong with the MAF SENSOR. I may
try cleaning it with something.
almost seems like it gets stuck there when crusin at 50 or accelerating. Im
beginning to think there is something wrong with the MAF SENSOR. I may
try cleaning it with something.
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Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
I still vote vacuum leak.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
Whats causing LTFT's to be high ?
Safety Car
Joined: Feb 2008
Posts: 3,712
Likes: 3
From: TEXOMA
St. Jude Donor '08-'09
do this, start engine. then take a cup of water and poor it over the intake near the fuel injectors, stay away from the coil packs. if the car misses then look for the leak.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
This thing is a challange.
This is a good way to leak check that part of the ststem. Still no go.
exactly the same 24.2 LTFT's on the scan. The next thing I done was install my pvc system with the valley being fed into the intake manifold.
Im testing A new CATCH CAN/SEPARATOR anyway. Same thing. No matter what I change that LTFT goes to 24.2 and stays there. I did see a small change in injector pulse width at idle but thats what it does to maintain a proper fueling. That MAF is comming out and I will see what the ECM displays by generating various KHZ signals into the ECM and see what the maf readout is in grams/sec > I have the equipment to do it and I will find out even if it requires installing the FAST 92 again.
Tech Contributor
Joined: Mar 2003
Posts: 12,094
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
why dont you clearance the FAST where the bolts were touching the manifold. This will let it sit properly.
+24 LTFTs isnt what you said before and that is indicative of a vacume leak.
+24 LTFTs isnt what you said before and that is indicative of a vacume leak.
Tech Contributor
Joined: Mar 2003
Posts: 12,094
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
why dont you clearance the FAST where the bolts were touching the manifold. This will let it sit properly.
Pegged at +24.2 LTFTs isnt what you said before and that is indicative of a vacume leak.
Pegged at +24.2 LTFTs isnt what you said before and that is indicative of a vacume leak.
I promise I will not get frustrated. I am a experimenter by nature. Love tinkering with things and learning. I currently have some issues with the 102. I got CEL's the second time and in checking the LTFT's Im seeing 14
to 20 suggestoing I got A leak there somewhere. I pull it today and do A look see and I still have the problem of the injector depth i mentioned before. I get PO171 & PO174 ( Lean banks) each side.
to 20 suggestoing I got A leak there somewhere. I pull it today and do A look see and I still have the problem of the injector depth i mentioned before. I get PO171 & PO174 ( Lean banks) each side.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Leon you have a vacuum leak. I'd try as Spin suggests to clearance the bolts. Vacuum leaks manifest themselves at idle mostly...cruise less so. Think about it, anytime your throttle is open you've got a huge vacuum leak so to speak so it'll run fine then. It's when the throttle is closed and the car is seeing more air than expected that you get the CEL.
If that doesn't work I'd re-seal the top of the manifold.
I wouldn't use water to test a vacuum leak - I have always used carb cleaner. If it speeds up, you found your leak, and, it dissolves with no residue. JMHO.
If that doesn't work I'd re-seal the top of the manifold.
I wouldn't use water to test a vacuum leak - I have always used carb cleaner. If it speeds up, you found your leak, and, it dissolves with no residue. JMHO.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,597
Likes: 3
From: READING PA
St. Jude Donor '08-'09-'10
Have you guys been reading my posts ?
nicely. The FAST 102 seats perfectly. Those 24.2 LTFT's are there no matter what. I have done leak diagnosis with the purge system and nothing changes. I have changed the table and nothing happens. ( LOW FREQ AIR MASS) . I got one more thing to check out and that is the MAF CKT. If thats ok and I still have PO 171 & 174 and LTFT's. Who said it was MAF Calibration. One more test and the 92 goes back on and let someone
else prove the PORTED 102 is better than the PORTED 92. So far I have seen nothing conclusive anywhere except in advertising and I know how that story goes.
Drifting
Joined: Jul 2009
Posts: 1,319
Likes: 64
From: Lakeville, MA
St. Jude Donor '10
silly question I'm sure, but you seem to be running out of options.... is the nipple on the back of the intake plugged?
I can't see your MAF taking a crap over night. If it's not the intake itself, than something with that intake install is causing the trims to correct a lean condition. You also mentioned the catch can....this is a new component intriduced to the mix, correct. Any chance that is leaking, either one of the lines, or the can itself??
I can't see your MAF taking a crap over night. If it's not the intake itself, than something with that intake install is causing the trims to correct a lean condition. You also mentioned the catch can....this is a new component intriduced to the mix, correct. Any chance that is leaking, either one of the lines, or the can itself??
Melting Slicks
Joined: Sep 2005
Posts: 2,184
Likes: 78
From: Corpus Christi Texas
Have you checked the vaccum lines on the intake to see that they are drilled out/open. When I put my FAST 92 I kept getting CEL's saying there was a leak. Don't remember which codes. Big head ache. Went over it several times. Turned out FAST never opened the nipple. It was on the purge line nipple.
Drifting
Joined: Sep 2009
Posts: 1,719
Likes: 4
From: cinnaminson n.j.
St. Jude Donor '14
Leon you have a vacuum leak. I'd try as Spin suggests to clearance the bolts. Vacuum leaks manifest themselves at idle mostly...cruise less so. Think about it, anytime your throttle is open you've got a huge vacuum leak so to speak so it'll run fine then. It's when the throttle is closed and the car is seeing more air than expected that you get the CEL.
If that doesn't work I'd re-seal the top of the manifold.
I wouldn't use water to test a vacuum leak - I have always used carb cleaner. If it speeds up, you found your leak, and, it dissolves with no residue. JMHO.
If that doesn't work I'd re-seal the top of the manifold.
I wouldn't use water to test a vacuum leak - I have always used carb cleaner. If it speeds up, you found your leak, and, it dissolves with no residue. JMHO.
If the ecm is adding 24% fule at 50mph and while accelerating, you do not have a vacuum leak. If there was a leak bad enough to cause a +24%ltft at 50 mph the engine would not idle at all. Spray some 2+2 into the intake behind the tb and watch for the stft to go negative verifying the o2's are working. Then check your fuel pressure and then sub in a known good maf.