got a good run today with the lt1 twin turbo and need input please
#1
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got a good run today with the lt1 twin turbo and need input please
ok today i finally got the car running top knotch. we only hit 10 psi we never cam off of the spring. but it laid down 720tq and 450 hp max
the 720 tq was only at 2700 rpm
the 450 hp was only at 4500 rpm
and we never lost boost until 7200 rpm when it hit the rev limiter
as soon as we hit the 720 tq it started to drop as the rpms went up.
and at 4500 to 5500 rpm we could not get any more hp after that. so we think the converter is slipping bad. and at 7200 rpms we are losing about a 1000rpm from hp tuners to the dyno.
and i drove it on the street after it was done and the thing was so fast i could barley hold it down even after 4500 rpms in middle to top of 3rd gear the front end started to lift and the *** started to float.
so how can a slipping converter pull hard after the 4500 rpm. and on the street it felt like it got faster and faster after 4500 rpms
any input
here is a link to the dyno pull. the pull went to 7200 rpm and the gragh only shows 4500 rpm ( its the only one i can get right now the paper gragh is to tiny to get a good pic of.
the 720 tq was only at 2700 rpm
the 450 hp was only at 4500 rpm
and we never lost boost until 7200 rpm when it hit the rev limiter
as soon as we hit the 720 tq it started to drop as the rpms went up.
and at 4500 to 5500 rpm we could not get any more hp after that. so we think the converter is slipping bad. and at 7200 rpms we are losing about a 1000rpm from hp tuners to the dyno.
and i drove it on the street after it was done and the thing was so fast i could barley hold it down even after 4500 rpms in middle to top of 3rd gear the front end started to lift and the *** started to float.
so how can a slipping converter pull hard after the 4500 rpm. and on the street it felt like it got faster and faster after 4500 rpms
any input
here is a link to the dyno pull. the pull went to 7200 rpm and the gragh only shows 4500 rpm ( its the only one i can get right now the paper gragh is to tiny to get a good pic of.
#3
Hmmm, how were they getting rpm data to the Dyno?
Some dyno's have a feature that allows the rpm to be derived from wheel (hub) speed. As you might imagine an auto trans and it's inherent slip doesn't work very well for that.
Or if they used an inductive pickup on a plug wire, they may have simply entered the wrong values in the rpm pickup settings. On my Dynojet you can tell the software that the plug fires every 180, 360, 720 degrees of crank rotation. Choosing the wrong one for the setup will obviously skew the numbers as well.
Some dyno's have a feature that allows the rpm to be derived from wheel (hub) speed. As you might imagine an auto trans and it's inherent slip doesn't work very well for that.
Or if they used an inductive pickup on a plug wire, they may have simply entered the wrong values in the rpm pickup settings. On my Dynojet you can tell the software that the plug fires every 180, 360, 720 degrees of crank rotation. Choosing the wrong one for the setup will obviously skew the numbers as well.
Last edited by J-tuneD; 06-07-2012 at 10:17 AM.
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You are blowing right through the converter. It will make power to a certain point and then the converter will just start to shear the fluid. You need a different stator in the converter. We have used a place called Midwest Converter in Rockford, IL. Ran into same problems before in the past and have picked up BIG mph and et. Give them a call, you won't regret it.