Single T76 LT1 Just Back from the Dyno-
#1
Single T76 LT1 Just Back from the Dyno-
Color me very happy!
Max PSI : 12
Max RWTQ: 571
Max RWHP: 574
Engine
=============
Displacement......: 355 ci
Heads.............: Stock LT1 Castings, ported by Will Garza
Fuel Injectors....: 60# Mototrons
Compression Ratio.: 8.8:1 Diamonds
Cam...............: Custom Bret Bauer Turbo Cam
Throttle Body.....: Stock 48mm
Intake Manifold...: Stock Lt1
Exhaust...........: Log Manifold, 3" pipe all the way back to 3" Dynomax Muffler
Machine work......: Jim Pitcher-Chatham, NY 12037
Fuel System
===========
Stock intank
NOS Inline pump
Stock lines
Stock Fuel Pressure Regulator
Tuning
=======
PCM Tuning........: Untouched Mail Order MAF tune by Bryan Herter @ PCM4Less
Transmission
============
Transmission......: Stock T56 Six Speed
Rear Gear ratio
===============
Differential......: 4.10:1 Ford 8.8 w/GM 10 bolt 'legs'
Turbo Specifics
===============
Turbo.............: TC 76 w/MPS Wheel .96 A/R(www.forcedinductions.com)
Intercooler.......: 3" OBX air to air, front mounted
Hotside...........: "RealQuick" log manifold system
Coldside..........: Ebay 3" Aluminum pipe/coupler/Tbolt kit
Water/Meth........: NO
Boost controller..: NO
Wastegate.........: TurboSmart 38mm w/14Psi springs
Blow off valve....: Tial 50mm w/11psi spring
Dyno Facility
=============
SGP Racing - Veterans Memorial, Houston, TX
RPM/Boost/TQ/HP Measurements(I had him start at 3K)
================================================
3,000 = 05 psi = 400 = 240
3,250 = 06 psi = 370 = 245
3,500 = 07 psi = 400 = 260
3,750 = 08 psi = 425 = 320
4,000 = 10 psi = 465 = 355
4,250 = 11 psi = 500 = 400
4,500 = 12 psi = 571 = 475 (We think the Wastegate opened after this)
4,750 = 11 psi = 571 = 525
5,000 = 11 psi = 565 = 548
5,250 = 11 psi = 560 = 560
5,500 = 11 psi = 540 = 565
5,750 = 11 psi = 525 = 570
6,000 = 11 psi = 500 = 574
6,250 = 11 psi = 475 = 565
Air fuel Ratio was 11.x:1 during 3K to 6K, then briefly went to 12.x:1
Weather conditions at the time of dyno:
1pm today 97 degrees F, 40% humidity, 29.9 barometric Pressure, dew point 69F
Test was through full exhaust, no dumps/cutouts. Air filter on. At 12 psi during the first pull, the reducer coupler at the compressor outlet popped off. Dan took a break while I got under there to put the coupler back on with a good T-Bolt. To my horror, I saw the Air filter was GONE. I remembered hitting some retread crap the other day when the car in front of me just went over it and I didn't have time to react but I didn't consider it could have wacked that low slung air filter. I don't know how long I've been driving around, drinking dirt into my new wonderful motor, but it's been at least 2 days. I bought a 3" cast aluminum elbow I found in SGP Racings Box 'o pipes and put that on there. I was frustrated when SGP didn't have a 4" K&N filter but Dan had Moshi drive me over to Pep Boys to get one, free of charge.
With that all back on and buttoned up we took the second pull. The TQ/HP lines on the graph are sooo smooth. Not jittery or having spikes and dips. This is an untouched/altered mail order turbo tune! Good Job Bryan!
I asked Dan why it was that a wastegate with 14psi springs would open up at 12psi and he said he's sees it a lot with cars that don't have boost controllers. He recommended I get a Blitz electronic boost controller so I'm going to pick that up next paycheck!
Jon (aka "RealQuick"), good job on the hotside!
Last edited by DirtyDaveW; 08-02-2008 at 05:02 PM.
#4
Very nice numbers. Those ported stock heads are performing well. You are very lucky to have your A/F ratio turn out to be right the first time. I used one of Bryans tunes for my base tune when I first got my supercharger. I still use it to pick and choose tables from.
#5
Thanks guys
This dyno (Dynapack) is different than any dyno I've been on before. They take your wheels off and bolt on these splined yokes. Each side of the car has a dyno box that the splined wheels go into. The great thing about this is there's no wheel slip/spin like occastionally happens on a conventional drum. The operator said it's the best kind of dyno for tuning. I know the "Mustang" dyno numbers read low compared to a dynojet numbers for a given car but I didn't know if this brand of dyno I was on today was 'optimistic' or 'pessimistic'. Tiago said it's actually quite pessimistic and he felt that my numbers on a dynojet would be over 600. It sure felt good to hear that.
This dyno (Dynapack) is different than any dyno I've been on before. They take your wheels off and bolt on these splined yokes. Each side of the car has a dyno box that the splined wheels go into. The great thing about this is there's no wheel slip/spin like occastionally happens on a conventional drum. The operator said it's the best kind of dyno for tuning. I know the "Mustang" dyno numbers read low compared to a dynojet numbers for a given car but I didn't know if this brand of dyno I was on today was 'optimistic' or 'pessimistic'. Tiago said it's actually quite pessimistic and he felt that my numbers on a dynojet would be over 600. It sure felt good to hear that.
Very nice numbers. Those ported stock heads are performing well. You are very lucky to have your A/F ratio turn out to be right the first time. I used one of Bryans tunes for my base tune when I first got my supercharger. I still use it to pick and choose tables from.
#7
It has turned out to be very nice for the daily driver aspect. You always hear about turbo lag but with the 4.10's it just jumps away from stoplights with a real urgency. Then on the freeway, the 6th gear takes charge and it's almost lugging the motor at 55mph.
My tires right now are the stock sized 245x50x16 Kuhmos I put on the car in 2003. They're fine for those 3rd gear and up romps but not of much use for anything below that. I'm looking at some new tires and rims but don't have a specific rim in mind other than a 17" rim, not garish and not too heavy. The tires, I just saw a listing for some 295 and 315's by M/T Street Radials that look good for the rears to me. On prior engines, I've gone thru 3 sets of Nittos and one set of BFG DR's so I know they are 'better' over all in performance but even my old setup could easily overcome those at the strip. I'll have a set of real slicks on separate rims soon for those days when I get to race at the tracks.
My tires right now are the stock sized 245x50x16 Kuhmos I put on the car in 2003. They're fine for those 3rd gear and up romps but not of much use for anything below that. I'm looking at some new tires and rims but don't have a specific rim in mind other than a 17" rim, not garish and not too heavy. The tires, I just saw a listing for some 295 and 315's by M/T Street Radials that look good for the rears to me. On prior engines, I've gone thru 3 sets of Nittos and one set of BFG DR's so I know they are 'better' over all in performance but even my old setup could easily overcome those at the strip. I'll have a set of real slicks on separate rims soon for those days when I get to race at the tracks.
#9
Yes! Me too! I'm so glad I'm at the point where I can enjoy the car, even though I'm still adding this and that. I'll go twin Walbro's in-tank within a month. As to the injectors and pump, I know. I've been reading the Forced Induction threads these past 3 years as I've been accumulating parts for this project and it seemed the common aspect of every success story was that the tune was imperative. Bryan Herter's name seemed to come up a lot so I tasked him with coming up with the tune. Far before I got the car running, I got the mail order tune and opened it up in my LT1 Editor. I'd been disappointed in past tunes from MTI and Ed Wright for my prior motor to see that they'd charged $275(MTI) and $350(FastChips) but had only (a) raised the rev limit (b) zero'd the knock tables (c) Turned the fans on early. In stark contrast, Bryan changed tons of stuff. The truth in the telling was actually driving the car once it was all together. Smooth running, A/F ratios stunningly right on the money whether cruising or boosting. I gave him every nuance of the setup in terms of hardware, goals and driving style and he seems to have pretty much nailed it. I'm sure there's probably more to be had by tweaking it, but for a baseline, I can't imagine how it could have been improved.
#11
Nice Dave!!!!!! Just think, with a little more boost and a nice set of AI or LE TFS heads, you should be able to hit 650-700rwhp on a dynojet. I think the dynapack reads lower than a dynojet because it loads the car like a mustang dyno.
#13
Dunno if I really want more power on my street car. It's absolutely hairy to drive at peak power as it is. I killed two 600cc sport bikes last Saturday night and it wasn't even a close contest. I admit those are small. I used to have a GSXR 1100 and a Ducati 916SS so those would be a better match. Just gotta go hunting for some liter bikes I guess
#14
I'd check your tune/logs... seems like you hit 400rwtq @ 5psi at 3000rpm, then you lose tq at 6psi, then hit 400rwtq @ 7psi at 3500rpm. Seems like you have a dip in the tq curve (fuel or spark related since there isnt any tire spin with a dynapack).
3,000 = 05 psi = 400 = 240
3,250 = 06 psi = 370 = 245
3,500 = 07 psi = 400 = 260
3,750 = 08 psi = 425 = 320
3,000 = 05 psi = 400 = 240
3,250 = 06 psi = 370 = 245
3,500 = 07 psi = 400 = 260
3,750 = 08 psi = 425 = 320
#15
Yes. It was odd in that way. It did exactly the same on both pulls though. The graph lines are very smooth, like ocean swells. I'll see if I can get the sheets scanned so I can post them.
I'd check your tune/logs... seems like you hit 400rwtq @ 5psi at 3000rpm, then you lose tq at 6psi, then hit 400rwtq @ 7psi at 3500rpm. Seems like you have a dip in the tq curve (fuel or spark related since there isnt any tire spin with a dynapack).
3,000 = 05 psi = 400 = 240
3,250 = 06 psi = 370 = 245
3,500 = 07 psi = 400 = 260
3,750 = 08 psi = 425 = 320
3,000 = 05 psi = 400 = 240
3,250 = 06 psi = 370 = 245
3,500 = 07 psi = 400 = 260
3,750 = 08 psi = 425 = 320