dyno results 408
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Staging Lane
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dyno results 408
I have recently changed the turbo on my 408 single set up. I originally had a gt4294 running 13 or 14psi boost made 560rwhp with heaps of pre turbine backpressure. Swapped to a diesel gt4708 with a 76mm comp inducer because it was bigger, free and fit without cutting much. Dynoed 627rwhp with 15psi boost and 780ftlb torque at 3200rpm. Pretty stoked with the results now got to wait for some track time. How does this dyno sheet look in comparison to other 408 with similar turbos and boost?
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But yes it should definitely make more steam but 500rwhp NA is a little far fetched if I assume its built how I think it is.
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You know NOTHING about his combo unless I missed something. Just like I know nothing about yours. Procharger size, compression ratio, heads, fuel, intake, timing, etc.
But yes it should definitely make more steam but 500rwhp NA is a little far fetched if I assume its built how I think it is.
But yes it should definitely make more steam but 500rwhp NA is a little far fetched if I assume its built how I think it is.
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To clear things up its a forged 408 with around 9to1 comp, medium sized turbo cam, turbo 400 with a tight 3000 slingshot converter, 9" with 2.75 ratio diff. car is a wb Holden statesman weighing 3800lb plus with me.
The Turbo kit I built myself, around a gt4294 I had originally planned on putting on the stock ls1 with the vortech. Which blew up due to a blow through carb issue. Knew the gt42 would probably be way too small for a 408. Made 560rwhp and ran 10.91 first run but could feel it choking so tested backpressure and stuff to confirm.
Got hold of a gt4780 for nothing and it fit without too much hassle. Got 627rwhp. Going to run it soon.
This car is a full weight street car that I drive when I am home. A Bigger turbo could be on the cards later.
The Turbo kit I built myself, around a gt4294 I had originally planned on putting on the stock ls1 with the vortech. Which blew up due to a blow through carb issue. Knew the gt42 would probably be way too small for a 408. Made 560rwhp and ran 10.91 first run but could feel it choking so tested backpressure and stuff to confirm.
Got hold of a gt4780 for nothing and it fit without too much hassle. Got 627rwhp. Going to run it soon.
This car is a full weight street car that I drive when I am home. A Bigger turbo could be on the cards later.
Last edited by StatoJase; 08-26-2013 at 08:03 PM.
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And I didn't think the 4708 was too small a turbo when I fit it. Its bloody huge but the wheels inside obviously don't represent the size of the housings. It was free, it was in good condition, and it is not laggy or anything for a primarily street car. Full boost as soon as its at 3000rpm. So I guess later on I will be looking for something around the 88 to 91mm range to benefit from the 408 cubes.
Last edited by StatoJase; 08-26-2013 at 08:08 PM.
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that power seems fine to me mate !!! stock heads ?? I,ve run 75mm and 88mm turbo's on a 408 !!!! our aussie dyno's are a bit low compared to some figures you see !!! anyway take it back to the track and see the real difference!!! cheers
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yeah stock l98/l76 heads from a ve ss donor engine I scored and built. I have flicked through your threads ittwgn. Nice set up. Our season in WA starts soon but at the moment I only go to the off street meets. My baseline is that 10.91 I ran last season so no matter what its quick for me. Just got to hit and leave with the 2 step this season to launch harder I think.
#15
Turbo specs
I have recently changed the turbo on my 408 single set up. I originally had a gt4294 running 13 or 14psi boost made 560rwhp with heaps of pre turbine backpressure. Swapped to a diesel gt4708 with a 76mm comp inducer because it was bigger, free and fit without cutting much. Dynoed 627rwhp with 15psi boost and 780ftlb torque at 3200rpm. Pretty stoked with the results now got to wait for some track time. How does this dyno sheet look in comparison to other 408 with similar turbos and boost?
Jeff