TT 61mm 347ci?
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I was wondering, I have heard many different comments on this topic.
I am thinking of doing a twin MP T61 or maybe TC 62 (t3/t4) on a stock cube LS1 with a 6 speed for my 2000 FRC.
Now would the t3/t4 cause too much back pressure? Ive read some thread people saying the t3 turbine side causes too much back pressure and will choke out even a 5.3L.
Im hoping if I need to go T4 based I can fit a T4 up in my fenders.
The cam of choice will probably be a 224-228 durration with a 114-116lsa.
Thinking either a speedinc TU1 (225/225 113lsa) or the tsp224 (224/224 114lsa)
For now it would be on a stock motor (prob stay around 6200rpm), then down the road upping to a forged motor and rev a bit higher.
I would like to keep it capable to do 700whp down the road.
Thanks for any input
Jay
I am thinking of doing a twin MP T61 or maybe TC 62 (t3/t4) on a stock cube LS1 with a 6 speed for my 2000 FRC.
Now would the t3/t4 cause too much back pressure? Ive read some thread people saying the t3 turbine side causes too much back pressure and will choke out even a 5.3L.
Im hoping if I need to go T4 based I can fit a T4 up in my fenders.
The cam of choice will probably be a 224-228 durration with a 114-116lsa.
Thinking either a speedinc TU1 (225/225 113lsa) or the tsp224 (224/224 114lsa)
For now it would be on a stock motor (prob stay around 6200rpm), then down the road upping to a forged motor and rev a bit higher.
I would like to keep it capable to do 700whp down the road.
Thanks for any input
Jay
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A guy i used to know ran a cam just like that with twin 60-1 t4 turbos on a stock 346 and ported 243's if i recall and 8.?:1 cr and made 800+rwhp on pump gas in a chevelle. All home built too! User name was nitrorocket if you wanna look up his threads and see what you can find. GL
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Also for the price would it be worth just moving up to twin MPT70s, I know they would be a bit overkill on a 347 but they are the same price as their T61.
Would be a T4 .68A/R
Jay
Would be a T4 .68A/R
Jay
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No room in my vette for a single, unless i did a hinsen kit and I dont like the kit. My plan was a single 78mm rear mount but I cant do a single rear mount unless I cut the trunk out which im not doing.
So I am dead set on twins, bc I can fender mount them.
Same setup as a UPP kit pretty much
Jay
So I am dead set on twins, bc I can fender mount them.
Same setup as a UPP kit pretty much
Jay
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Not sure how those would spool up on stock disp. I'm pretty sure he could have gotten close to 1000rwhp with the 60-1's. I'd say go no bigger than twin 62's but i'm no turbo expert by any means! Talk to Jose @ forced inductions on here. He will know what you can get away with if you wanna go bigger!
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I was kinda leaning toward MPs for the price. I also considered turbonetics t3/t4 62-1s since they are 721 a piece on treadstones site.
I would like to stay 700ish and under per turbo. im gonna be collecting all the parts over the next 8 months or so.
Jay
I would like to stay 700ish and under per turbo. im gonna be collecting all the parts over the next 8 months or so.
Jay
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I think your 5.7 should spool those without ado
another thing that ive heard is the since the master power t4 turbos use the same basic hotside from t60 -t76, spool will be similar, but the t70 will give more headroom. the only thing to be worried about would be surge, and looking at the maps and plotting a 5.7 against it, I dont believe a 5.7 would go into surge with two t70s.
so im saying, the t60s would be AMAZING for your power goals, but the t70 would work equally as well, and shouldnt give up any noticeable spool since the hotside is the same
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After doing a lot of compressor maps on some 60mm,66mm and 70mm turbos for a stock 5.7L it looks like twin 66mm would be perfect, twin 70s seem to put it right in the sweet spot but once you start cranking the boost on them it seem to get close to the surge limit but the turbo speed seems decent.
Twin 60s look like they would be perfect from the 10-14psi after that your really turning some rpm on them. For my goals I think the MP T61s would be good but for future plans with them I feel they would hope me back a bit. I think some 66-67s (MP42) would be mint but seem to go for a bit more money then the MPT70s
So I think I will be keeping my eyes open for some T4 66-70mm turbos with under a .70 A/R
Hopefully I did my math right on the compressor maps, I based it all of a VE of around 95% and 7000rpm. So there are many variables that come into play that will change my plot numbers.
Thanks for all the help on the above posts!
Now to get some vendors to start a bidding war hahah
T61 and T70s seem to go for 599.99, now I shall price some MP42s and see!
Jay
Twin 60s look like they would be perfect from the 10-14psi after that your really turning some rpm on them. For my goals I think the MP T61s would be good but for future plans with them I feel they would hope me back a bit. I think some 66-67s (MP42) would be mint but seem to go for a bit more money then the MPT70s
So I think I will be keeping my eyes open for some T4 66-70mm turbos with under a .70 A/R
Hopefully I did my math right on the compressor maps, I based it all of a VE of around 95% and 7000rpm. So there are many variables that come into play that will change my plot numbers.
Thanks for all the help on the above posts!
Now to get some vendors to start a bidding war hahah
T61 and T70s seem to go for 599.99, now I shall price some MP42s and see!
Jay
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J Ask Jose about some GT61's. They can do the exhaust however you want. He quoted me a killer price a few years back for 2. The 61mm Tnetics with the 62mm f wheel look to be damn close to ideal on a 347. The 6165 setup will do 900whp on a 355. Very close to a PT88 single but twins instead.