New Comp 80mm,17psi,370ci, auto,777whp!DYNO SHEET ADDED!
#22
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hydrosteam, not sure why it peaks alittle earlier. It is a t4 turbo which will only go so far. Do you have a graph on your car? Did you dyno it locked or unlocked?
#23
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My tuner did say that he thinks my intercooler is restrictive due to the fact thats its an ebay cooler and the way the fitting are welded on is not ideal for flow. Last time on the dyno I had a 4psi drop before and after the intercooler.
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Hmm i wonder how it would have looked with the load of the converter locked up. Im sure you would be close to 800whp. Maybe someone can chime in about what a graph shows with a unlocked vs locked as far as peak rpm.
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Seems like I am always the one to throw the wrench in lol...
This isn't true. Backpressure will generally rise linearly with boost, the ratio of which is determined by the sizing of the turbine and compressor, and their respective housings. The turbine housing will only flow so much, so once flow becomes a limitation, two things happen: backpressure will induce negative torque because of the exhaust duration of your cam, and the exhaust pressure will not be able to feed the turbine fast enough, so your boost will begin to die off. I can see this actually happening on your car because the torque falls off hard after it peaks. I've seen this on a dyno many times. Ask your tuner what boost looked like during the run, I'll bet you lost 3-4psi after it peaked. I bet you pick up 50hp with a smaller cam
This isn't true. Backpressure will generally rise linearly with boost, the ratio of which is determined by the sizing of the turbine and compressor, and their respective housings. The turbine housing will only flow so much, so once flow becomes a limitation, two things happen: backpressure will induce negative torque because of the exhaust duration of your cam, and the exhaust pressure will not be able to feed the turbine fast enough, so your boost will begin to die off. I can see this actually happening on your car because the torque falls off hard after it peaks. I've seen this on a dyno many times. Ask your tuner what boost looked like during the run, I'll bet you lost 3-4psi after it peaked. I bet you pick up 50hp with a smaller cam
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Smokeshow, I didn't think my cam was that big compared to alot of guys. Its a 232/236 low .600ish lift on a 115+4 lsa. Could I really be lossing 50whp running this cam?