Quote:
Originally Posted by TRBOBUICK
Does that have something to do with how much load the dyno is putting on the rear tires?
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Quote:
Originally Posted by TRBOBUICK
Does that have something to do with how much load the dyno is putting on the rear tires?
Im not sure. Sean had the load cranked up on both of our cars. Important thing is the 02's are commanded for a safe a/f and thats what counts. Sean is going to help me with some track tuning.
I am still mistified by brians lack of boost building on the dyno. Dans car seems not to have that trouble however. Here is Dans Dyno sheet since i was asked to post it.Quote:
Originally Posted by orangejuiced86
Sean
Quote:
Originally Posted by robh
Rob,
That's a good way to describe the power curve on this thing - like a turbo diesel. It hits hard and quick and just seems to keep pulling. I was experimenting a little bit at my super-secret, late-night, dragrace spot and the car seems to go faster as I short-shift the thing, sorta like a diesel truck!
Give me a call and I'll walk you through the math that Raj and I were talking about - 734.968.3570
Dan
Dan PM that place. Maybe the Trunk and I met you there.Quote:
Originally Posted by dpmcghee
hp per cube and total airflow avialable say nope 90 lb/min. the Compressor is looking like its out of air. We never did see the waste gate open. the TQ is there to make close to 800hp but the RPM for the TQ curve is really low. Retarding the camhsaft 6-8 degree might move it upstairs enough to bring the top end power out. the total flow of the compressor given optimal conditions is 90lbs minute. divide like soQuote:
Originally Posted by robh
90 lb minute ( flow ) /.0807 ( wieght of cubic foot of air )
90/0.0807 = 1115.24 cfm
the TQ is there to support the engine using all of the aviable flow IMO. From what Ive seen over the years about 2cfm per ft lb is fairly normal. ive seen it as efficient as 1.75cfm pr ft lb and as bad as 2.25 but either way its middle of the road. given the bore stroke combination head flow and the ever critical runner length the TQ curve make sense to me.
I think the most important thing to note is power under the curve. This car makes literally gobs of power under the curve and If it were drag racing id shift it at 5600-5800rpm. it doesn't exhibit any of the normal problems seen with turbo cars like peaky power output. the turbo come on hard at around 3500rpm and stays on till around 5800rpm. nice wide power curve the car should hual some serious ass.
Sean,
Thanks for posting some of the info. I'm not completely familiar with his combo i.e. c.i., heads but I thought he was running a t76.
I didn't quite understand your formula as I always use these for my own stuff:
(CID X RPM) / 3456 =CFM
CFM = (CID X RPM) / 3456 X VE
Assuming VE to be around 85%
CFM X .069 = LBS/MIN
I don't claim to be an expert as I only read the Turbocharging guide by Spencer Brown. I also don't want to post all of Dan's set up info on here either. Good luck to Dan in search for more boost!!!
I would imagine that your car should put down more boost than that. The dyno probly did not just load the motor enough.
That in turn will not get the turbo spooling.
You sould be right around 8-900 hp maxed out wtih a 76 with the combo you have mentiond....
What an awesome combo! I want a torque curve like that in my Z28. That thing must be a blast to drive!
-Geoff
Dont get hung up on dyno numbers. A t-76 will never support 900 at the tires.Quote:
Originally Posted by 1slow305