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AES 398 - Turbo Size EDIT: Alright, sold my GTK-850. Closing in on choosing a turbo.. Been talking to Justin @ comp turbo. I want around 1100rwhp eventually.. Specs on 398 - LQ9 Block. TFS LS220 65cc heads. 4.030 bore, -15cc dish, 1.140ch. 3.900 crank, 6.125 rod. 9.4:1 rough cr. Custom comp roller approx 232 232 580lift 114lobe. New holley efi front inlet. Will be running on aus98 fuel (93us). Probably with meth injection. T56 gearbox. Moser 12bolt. Will a Comp Turbo oil less CT5X 8279 suit my application? I know it's a little smaller than the usual 88/91mm. But these comp turbos flow better, spool up easier, etc. I think this one is around 142lbs/min. *HP rating is 1350 What size housing should i get? 90 T4 divided 4" V band 1.00 T4 divided 4" V band 1.10 T4 divided 4" V band 1.25 T4 divided 4" V band .90 T6 open 5" V band 1.08 T6 open 5" V band 1.23 T6 open 5" V band 1.39 T6 open 5" V band 1.00 Tial SS v-band inlet/outlet 1.16 Tial SS v-band inlet/outlet 1.30 Tial SS v-band inlet/outlet Any help is appreciated. Thanks Jeremy Hey guys, first topic here... Be nice. Building a 67 Nova streetfighter. Have ordered an AES398 from Fraser. Using a T56. What is the ideal turbo size? I want to make around 1000-1200rwhp on 98octane fuel. (USA 93 octane). I currently have 1x Turbonetics GTK-850 oil only turbo. Brand new. Kind of a waste if i don't use it. So should i buy another one and go twins? Or some kind of 91mm single turbo? Advantages and disadvantages of both plz? Room isn't really an issue, using TCI Pro Touring front clip. So i can cut into fenders etc. Thanks Jeri |
I don't have an answer for you, but I'm subscribing to see what people have to say. Make sure you fire up a build thread for everyone to see! |
Originally Posted by Anchor
(Post 16334805)
Hey guys, first topic here... Be nice. Building a 67 Nova streetfighter. Have ordered an AES398 from Fraser. Using a T56. What is the ideal turbo size? I want to make around 1000-1200rwhp on 98octane fuel. (USA 93 octane). I currently have 1x Turbonetics GTK-850 oil only turbo. Brand new. Kind of a waste if i don't use it. So should i buy another one and go twins? Or some kind of 91mm single turbo? Advantages and disadvantages of both plz? Room isn't really an issue, using TCI Pro Touring front clip. So i can cut into fenders etc. Thanks Jeri You could easily do twins, or go to a single GT91 if your on a budget. Either setup would reach those #'s. Twin GTK's though would allow for more room later down the road. |
Originally Posted by DrTurbo
(Post 16335459)
You could easily do twins, or go to a single GT91 if your on a budget. Either setup would reach those #'s. Twin GTK's though would allow for more room later down the road. Thanks |
You had better make sure that your t56 will hold the power. Most seem to crap out around 800 or so ftlbs of torque. |
Originally Posted by rwb
(Post 16337163)
You had better make sure that your t56 will hold the power. Most seem to crap out around 800 or so ftlbs of torque. |
Alright, sold my GTK-850. Closing in on choosing a turbo.. Been talking to Justin @ comp turbo. I want around 1100rwhp eventually.. Specs on 398 - LQ9 Block. TFS LS220 65cc heads. 4.030 bore, -15cc dish, 1.140ch. 3.900 crank, 6.125 rod. 9.4:1 rough cr. Custom comp roller approx 232 232 580lift 114lobe. New holley efi front inlet. Will be running on aus98 fuel (93us). Probably with meth injection. T56 gearbox. Moser 12bolt. Will a Comp Turbo oil less CT5X 8279 suit my application? I know it's a little smaller than the usual 88/91mm. But these comp turbos flow better, spool up easier, etc. I think this one is around 142lbs/min. *HP rating is 1350 What size housing should i get? 90 T4 divided 4" V band 1.00 T4 divided 4" V band 1.10 T4 divided 4" V band 1.25 T4 divided 4" V band .90 T6 open 5" V band 1.08 T6 open 5" V band 1.23 T6 open 5" V band 1.39 T6 open 5" V band 1.00 Tial SS v-band inlet/outlet 1.16 Tial SS v-band inlet/outlet 1.30 Tial SS v-band inlet/outlet Any help is appreciated. Thanks Jeremy |
Go bigger, the comps do spool very fast which will allow you to run a larger turbo |
91mm will get you to 1100rwhp no probs. |
Turbine size is what will be the choke point. I wouldn't use anything with a turbine wheel smaller than 94mm no matter the brand turbo. Doesn't matter if the bearings ride on astro glide the turbine wheel is always the choke point.:) |
Ok but i don't want to go any further than around 1100. Don't want to stress the block/head relationship lol.. Howcome the guys at comp turbo recommend the smaller one? This is all new to me.. I would also like to stay oil less. Don't think they do a larger frame turbo in oil less. |
Originally Posted by Anchor
(Post 16556861)
Ok but i don't want to go any further than around 1100. Don't want to stress the block/head relationship lol.. Howcome the guys at comp turbo recommend the smaller one? This is all new to me.. I would also like to stay oil less. Don't think they do a larger frame turbo in oil less. ray @ unleashed performance seems to be the guy doing the oil less turbo system. you may want to talk with him. i think its a butt mount but its custom and they are starting to get those down pat anyways these days. Longrange4u with a 91mm rear mount and with the tuning of LMR and even at over 3700-3900 lbs with the iron block I believe hes going low 9's and making around 1100. seems like the enging was aes 390.....or he may have swapped it to LMR 408. pm him and ask about it. |
Ya 79mm on a 398 is small. What it the biggest turbine wheel they can fit? That's a t4 turbo right? |
Righto, just emailed justin back asking what the biggest i can go is on an oil less turbo. |
Comp always recommends a small turbo. I just don't think deal with these big engines alot. |
I would go twins, but I always say that as I prefer the way they drive. Something in the range of PT6266's would have awesome response and efficiently meet your power goal. |
Yeah twins would be cool.... But more expensive? |
Originally Posted by INTMD8
(Post 16557227)
I would go twins, but I always say that as I prefer the way they drive. Something in the range of PT6266's would have awesome response and efficiently meet your power goal. |
Originally Posted by Fbodyjunkie06
(Post 16556814)
Turbine size is what will be the choke point. I wouldn't use anything with a turbine wheel smaller than 94mm no matter the brand turbo. Doesn't matter if the bearings ride on astro glide the turbine wheel is always the choke point.:) |
Originally Posted by I8UR4RD
(Post 16557018)
ray @ unleashed performance seems to be the guy doing the oil less turbo system. you may want to talk with him. i think its a butt mount but its custom and they are starting to get those down pat anyways these days. Longrange4u with a 91mm rear mount and with the tuning of LMR and even at over 3700-3900 lbs with the iron block I believe hes going low 9's and making around 1100. seems like the enging was aes 390.....or he may have swapped it to LMR 408. pm him and ask about it. |
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