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Hey guys I had the truck tuned Friday and wanted your thoughts on my dyno chart. Power seems to fall of rather soon and seems a little low to me. Motor is a 2001 ls1, forged bottom end, 70mm w/ .96 ar turbo, speed inc tu1 cam, approx 9#'s of boost and an alky kit. 4l60e, Ford 9" rear end with 3.89 gears and a Detroit trutrac. AFR is good and I believe he said the timing is around 16* at the top.
Hey guys I had the truck tuned Friday and wanted your thoughts on my dyno chart. Power seems to fall of rather soon and seems a little low to me. Motor is a 2001 ls1, forged bottom end, speed inc tu1 cam, approx 9#'s of boost and an alky kit. 4l60e, Ford 9" rear end with 3.89 gears and a Detroit trutrac. AFR is good and I believe he said the timing is around 16* at the top.
Power looks to be a bit low, but the torque is extremely low. Which to me is shocking, especially given the cam choice.
The point where the power drops off rpm wise seems to be inside the "normal" zone... I would have thought your numbers would have been around 100 more on both hp and tq.
The power is falling off early due to the small turbo/exhaust wheel. Same thing happened to me with a MP70 turbo with 346 cubic inches. Was the converter locked? Regardless, me thinks the trans/converter and that rearend are eating up power. Not a real well optimized setup for big power, but I think its right on considering these factors and only 9psi. That similar combo I'm speaking to made 616 to the tire thru a 6 speed and 12 bolt @ 15psi - but went flat at 5300 and was down like a rock by 5800 due to exhaust housing restriction.
Forged bottom end only 9lbs? Spraying meth? Let that baby eat and turn up the boost bud. Otherwise you got a rig you can beat on all day long and not fret about... nice work
The power is falling off early due to the small turbo/exhaust wheel. Same thing happened to me with a MP70 turbo with 346 cubic inches. Was the converter locked? Regardless, me thinks the trans/converter and that rearend are eating up power. Not a real well optimized setup for big power, but I think its right on considering these factors and only 9psi. That similar combo I'm speaking to made 616 to the tire thru a 6 speed and 12 bolt @ 15psi - but went flat at 5300 and was down like a rock by 5800 due to exhaust housing restriction.
Agreed, he is outta turbine wheel for sure. If it's a on3 70, gna need twins to get rid of that exhaust flow. I run .81 on them with a 5.3 and they spool great, newer deal has .68 and they should carry me over 7400, but again each is dealing with 4cyls of exhaust flow
Not sure who's 70mm you are running but you shouldn't be out of exhaust wheel yet. Does the boost drop off at upper rpm's? On our dyno we see boost/power fall off as a turbo starts to choke out. We typically see 600rwhp on 70mm's through auto's here before they are done. More cubes will choke them out faster. While not ideal I think your numbers are a bit lower than typically due to your drive line. Our last L33 did just over 500/600 at 9ish pounds through a th400 with similar timing to yours. Every dyno will spit out different numbers though. Spraying meth at 9lbs probably isn't helping either.
Is it a load bearing dyno? Before we added a brake to ours we would loose 2-3lbs on a pull as we were just spinning a 2,000lb roller. Do you have a log of the dyno pull?
Not sure who's 70mm you are running but you shouldn't be out of exhaust wheel yet. Does the boost drop off at upper rpm's? On our dyno we see boost/power fall off as a turbo starts to choke out. We typically see 600rwhp on 70mm's through auto's here before they are done. More cubes will choke them out faster. While not ideal I think your numbers are a bit lower than typically due to your drive line. Our last L33 did just over 500/600 at 9ish pounds through a th400 with similar timing to yours. Every dyno will spit out different numbers though. Spraying meth at 9lbs probably isn't helping either.
Is it a load bearing dyno? Before we added a brake to ours we would loose 2-3lbs on a pull as we were just spinning a 2,000lb roller. Do you have a log of the dyno pull?
I'm running a Masterpower 70mm. Yes it was a load bearing Dyno. I don't have the dyno log but I might be able to get it. The truck runs really good just thought I'd get more out of it. Hot side piping is 2.5" and the exhaust is 3" into a spintech muffler. Are you saying the meth is hurting or not really doing anything?
The reasons you're not getting more are mentioned above, and confirmed with your last post. Swap the turbo to an on3 76/65 or 78/75 and it'll run better in every respect with more room to grow (especially with the 78/75).
04-16-2018, 10:06 PM
Dyno numbers are in! 
