Poor gains with ported fast 92 intake
04-08-2009, 04:31 PM
#1
Poor gains with ported fast 92 intake Back in December I had Vengeance replace my LS6 intake & Shaner TB with a ported 92mm FAST and a BlueMaxx TB. It was already late by the time they finished, and they had LS1Edit to tune with which is POS by today's standards. Plus, I have HPTuners and have done well street tuning the previous combinations. I kept the Whisper Lid and the stock MAF connected.
The 2 dyno runs I made with the Fast combo was basically the same results as the LS6 intake combo dyno done about a month earlier, right around 420rwhp/400rwtq. I'll see if I can grab the files for comparison, I don't have them here at work. But I see there is another dyno day next weekend at the same shop and I thought I might try it again.
Since then I've removed the stock MAF, installed a Fast 85mm LIid, replaced the bellows, and re-tuned the VE tables. It doesn't feel as snappy off idle as it did with the other maf/lid/bellows, but it seems stronger starting around 2500-3000RPM.
So what I want to begin looking at is mechanical reasons why it was/is so weak... poor sealing, bolts loose, loose fittings, oil in intake, etc, etc, that I can check... I briefly played with the idea of having the car professionally tuned but I want to pay for results, not time.... and if there's a mechanical issue that's more time. Plus, I run OLSD and there doesn't seem to be too many 'pro' tuners locally who are comfortable with a true OLSD tune. I don't want to buy a bigger MAF to find it's an expensive bandaid which fixes nothing.
Motor Mods off the top of my head:
FTRA, Fram filter, FT 85mm lid, Spectre hose, Blue Maxx TB, Vengeance ported 92mm FAST, FAST intake gaskets, LS7 lifters, Crane 7.400" 3/8" pushrods, 226/232 .609/.604 110+2 cam, TSP 58cc 5.3l heads, .040 Cometic gaskets, Wiseco -2cc pistons, Eagle rods, stock crank, ARP rod bolts, ARP main bolts, Katech oil pump, Norris catch can, LS6 valley cover, AR 1.75" headers & catt'ed y-pipe, cut-out, wideband sensors in both collectors, ASP crank pulley, 480-498cc/min Lucas injectors but otherwise stock fuel system
Edit: Typos & added missing mods
The 2 dyno runs I made with the Fast combo was basically the same results as the LS6 intake combo dyno done about a month earlier, right around 420rwhp/400rwtq. I'll see if I can grab the files for comparison, I don't have them here at work. But I see there is another dyno day next weekend at the same shop and I thought I might try it again.
Since then I've removed the stock MAF, installed a Fast 85mm LIid, replaced the bellows, and re-tuned the VE tables. It doesn't feel as snappy off idle as it did with the other maf/lid/bellows, but it seems stronger starting around 2500-3000RPM.
So what I want to begin looking at is mechanical reasons why it was/is so weak... poor sealing, bolts loose, loose fittings, oil in intake, etc, etc, that I can check... I briefly played with the idea of having the car professionally tuned but I want to pay for results, not time.... and if there's a mechanical issue that's more time. Plus, I run OLSD and there doesn't seem to be too many 'pro' tuners locally who are comfortable with a true OLSD tune. I don't want to buy a bigger MAF to find it's an expensive bandaid which fixes nothing.
Motor Mods off the top of my head:
FTRA, Fram filter, FT 85mm lid, Spectre hose, Blue Maxx TB, Vengeance ported 92mm FAST, FAST intake gaskets, LS7 lifters, Crane 7.400" 3/8" pushrods, 226/232 .609/.604 110+2 cam, TSP 58cc 5.3l heads, .040 Cometic gaskets, Wiseco -2cc pistons, Eagle rods, stock crank, ARP rod bolts, ARP main bolts, Katech oil pump, Norris catch can, LS6 valley cover, AR 1.75" headers & catt'ed y-pipe, cut-out, wideband sensors in both collectors, ASP crank pulley, 480-498cc/min Lucas injectors but otherwise stock fuel system
Edit: Typos & added missing mods
Last edited by JimMueller; 04-09-2009 at 08:53 AM.
04-08-2009, 09:14 PM
#2
Jim, sorry I missed you when you came up for the install.
FWIW, Mike used EFI Live and occasionally HP Tuner if a customer requests it. We havent used LS1 Edit in YEARS... If you would like to send a copy of your tune over we would be more than happy to take a look and see if anything sticks out.
Dont get caught up in buying MAFs etc... We have done plenty of testing and the MAF definately wouldnt be a restriction with your combo.
Something simple to check, make sure your TB is going 100% when you press the pedal to the floor.
Also, M6 or A4? #s seem low for an M6 even before the intake....
Give me a call if we can help you out with anything
FWIW, Mike used EFI Live and occasionally HP Tuner if a customer requests it. We havent used LS1 Edit in YEARS... If you would like to send a copy of your tune over we would be more than happy to take a look and see if anything sticks out.
Dont get caught up in buying MAFs etc... We have done plenty of testing and the MAF definately wouldnt be a restriction with your combo.
Something simple to check, make sure your TB is going 100% when you press the pedal to the floor.
Also, M6 or A4? #s seem low for an M6 even before the intake....
Give me a call if we can help you out with anything
04-11-2009, 08:30 AM
#3
Did you ever think that your heads/cam can't handle all the extra flow from the bigger intake and TB? Your engine can only suck as much air as the heads and cam will dictate no matter how big your intake system is.
04-12-2009, 09:43 AM
#5
Idle was originally a bit high when I got home with the new intake, and found one bolt completely loose and some of the others a bit loose. I guess they worked themselves loose? The current idle doesn't surge nor idle high.
Camarorat: What I'm saying is I want the tuner to only worry about calibration issues, not mechanical issues. I want any mechanical issues resolved before I visit a tuner.
Camarorat: What I'm saying is I want the tuner to only worry about calibration issues, not mechanical issues. I want any mechanical issues resolved before I visit a tuner.
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04-12-2009, 04:36 PM
#8
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Must be something mechanical. Everyone else seems to gain a lot of power with one Ron's Ported FAST 92's. Have you verified that your Bluemaxx TB is opening 100%?
I know I had issues with my 95mm REV Xtreme closing 100%. Terry at REV fixed and she's perfect now. Hopefully its something simple as that. Best of luck, and please update us as soon as you get everything correct. Should definately make more power with a ported 92mm fast from RON at Vengeance vs the ls6. +20 or more in some cases.
I know I had issues with my 95mm REV Xtreme closing 100%. Terry at REV fixed and she's perfect now. Hopefully its something simple as that. Best of luck, and please update us as soon as you get everything correct. Should definately make more power with a ported 92mm fast from RON at Vengeance vs the ls6. +20 or more in some cases.
04-12-2009, 05:43 PM
#9
I'm waiting to hear back from Mike at Vengeance regarding my current tune. I was mildly irked that I needed to sand the TB bore and alter the TPS sensor for a TB that was "the same as the Nick Williams, just cheaper". I believe installation should mean proper installation and validation that there aren't any mechanical issues.
Throttle goes to 100%. What's that stuff you spray around the intake to see if it has a vacuum leak? The block was milled .020, the heads milled to 58cc, and the head gasket dropped .016. I had some fitment problems with the LS6 intake as a result, but only before modifying the alignment feet. We supposedly used new Fast intake gaskets also, although I've heard the stock intake gaskets may seal better?
I guess I could pay for a compression but wet or dry? I had the heads flowed last year and I know other PRC 5.3l owners have picked up with the ported Fast. Since Steve loves me so much, maybe he'd give my current tune the once over to see if there's anything obviously out of whack in the tune
Throttle goes to 100%. What's that stuff you spray around the intake to see if it has a vacuum leak? The block was milled .020, the heads milled to 58cc, and the head gasket dropped .016. I had some fitment problems with the LS6 intake as a result, but only before modifying the alignment feet. We supposedly used new Fast intake gaskets also, although I've heard the stock intake gaskets may seal better?
I guess I could pay for a compression but wet or dry? I had the heads flowed last year and I know other PRC 5.3l owners have picked up with the ported Fast. Since Steve loves me so much, maybe he'd give my current tune the once over to see if there's anything obviously out of whack in the tune
04-19-2009, 04:17 PM
#12
I drove the car around 10:30AM running some errands, then it sat until 2PM. Ryan with the compression gauge was to be here at 2PM so I wanted to get a head start on getting things disassembled. I had almost started pulling spark plugs when he called to advise he was on his way, and he requested I run the car for just 20s before pulling the rest of it apart.
Cylinders 1,2,7,8: 160
Cylinders 3,4,5: 165
Cylinder 6: 170
That was with turning the engine over ~3 times. Whistler thought with the SCR of 11.4 that it should reach a higher number, so we re-tested #1 turning over ~6 times, and that yielded between 195-200. I inferred there was a question on why it didn't build more compression sooner.
The port alignment between the intake and the heads was off about 2/16" of an inch on the floor of intake port 1. Intake gaskets are red, which I presume are the FAST gaskets.
Cylinders 1,2,7,8: 160
Cylinders 3,4,5: 165
Cylinder 6: 170
That was with turning the engine over ~3 times. Whistler thought with the SCR of 11.4 that it should reach a higher number, so we re-tested #1 turning over ~6 times, and that yielded between 195-200. I inferred there was a question on why it didn't build more compression sooner.
The port alignment between the intake and the heads was off about 2/16" of an inch on the floor of intake port 1. Intake gaskets are red, which I presume are the FAST gaskets.
Last edited by JimMueller; 04-19-2009 at 06:20 PM.
