Twin Turbo 4.8 Results / Single 80mm Build
09-18-2017, 09:08 AM
#21
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I haven't seen many use them on LS stuff, but they seem pretty popular on Coyote cars. He posts on YB all the time, I'm sure you have seen his car. Its a black Chevelle, 6.0L that runs in 5s at 120+.
http://www.yellowbullet.com/forum/sh...php?p=58389473
http://www.yellowbullet.com/forum/sh...php?p=58389473
09-18-2017, 10:01 AM
#22
Forgot Del had the small turbos. His car runs great, pretty heavy too. That’s what I’m talking about though. 72/68’s should perform MUCH better, even at 20lbs. That Chevette should be flying at 30lbs.
At 8.6:1 the 5.3 on my 3000lb rx7 was trapping 148 @ 20lbs and 153 @ 25ish lbs (pumping hot air at that point). That’s with the small wheel cast S475 T4 deal and LS9 cam. The T4 S476 was going 150-151 @ 19-20lbs on the 4.8 with trip12 cam and untouched 706 heads.
Also saw you could get the Holset HX35/HY35 clones with the billet 60mm wheels pretty cheap now($340). They performed crazy well on the 2.0 stuff I use to run. Making well into the 600 crank zone on a single.
At 8.6:1 the 5.3 on my 3000lb rx7 was trapping 148 @ 20lbs and 153 @ 25ish lbs (pumping hot air at that point). That’s with the small wheel cast S475 T4 deal and LS9 cam. The T4 S476 was going 150-151 @ 19-20lbs on the 4.8 with trip12 cam and untouched 706 heads.
Also saw you could get the Holset HX35/HY35 clones with the billet 60mm wheels pretty cheap now($340). They performed crazy well on the 2.0 stuff I use to run. Making well into the 600 crank zone on a single.
Last edited by Forcefed86; 09-18-2017 at 10:21 AM.
09-18-2017, 10:20 AM
#23
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Between Dario's Chevette, Tony Reiners Mustang and my car I think we can conclude these turbo just aren't great. The rest of my combination isn't ideal for this engine/turbo size but it should still be making quite a bit more power. I think those 61/65's would be a really nice option, they should light off pretty quick even on a 4.8. The re
09-20-2017, 06:09 AM
#24
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I had those turbos on a 4.8 with 862s and a tu0 in a awd full size and they were far too laggy for my combo.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
09-20-2017, 06:57 AM
#25
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I had those turbos on a 4.8 with 862s and a tu0 in a awd full size and they were far too laggy for my combo.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
09-20-2017, 07:05 AM
#26
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Man, there seems to be a strong case for staying away from these Rev9 7268s. I just got my BMW 540i6 (DOHC 4.4L V8) on the road with a single one. Guess like I'll be changing out the turbo fairly soon lol...
09-20-2017, 01:53 PM
#27
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One started bleeding a little behind the air filter, the other was fine. I cleaned it out and it stayed clean for a while. Decided it wasn't enough of a leak to be a problem.
The new ones are holding up great. Much better response.
I saw the same 6000rpm spool as you, even with very aggressive tune to try to light them off.
The rev9 stuff is hard to beat for $500/pair in my opinion.
The new ones are holding up great. Much better response.
I saw the same 6000rpm spool as you, even with very aggressive tune to try to light them off.
The rev9 stuff is hard to beat for $500/pair in my opinion.
09-20-2017, 03:06 PM
#29
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Unfortunately I dont really plan to take the truck to the track anytime soon and I'm not too interested in finding and paying for an awd dyno near me. My evo is broken and my 73 wagon doesn't have seat belts so the truck is my only driver at the moment. Isn't hot rodding fun?
I did make sure to get some good back to back logs between the turbos. I never collated any of the data like I hoped to though.
I did make sure to get some good back to back logs between the turbos. I never collated any of the data like I hoped to though.
09-27-2017, 11:50 AM
#30
I had those turbos on a 4.8 with 862s and a tu0 in a awd full size and they were far too laggy for my combo.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
i bought rev9 66/62s and have been running those and they seem a lot better. The iats stay reasonable even at 19psi on pump gas. Not sure how the power is, I haven't tried reading plugs or hitting the track yet but the truck has walked everything I've met on the street. Which isn't really saying too much I guess.
09-27-2017, 12:57 PM
#31
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09-28-2017, 06:32 AM
#34
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