Turbo/component selection 347...
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From: Port Tobacco, MD
Turbo/component selection 347... Here's the combo....
Built 347
ET heads 11 degree 225cc
Cam who knows 230/230 116lsa
~9.0:1
Tube style manifolds 1.75" SS with merge collector
twin 3" downpipes
twin PT-61mm turbos .68 or .81????
3" pipes to the turbos
3" pipes to the IC
4" pipe from the IC to the TB
90mm TB
twin 38 wastegates externally vented 1.5" dump tubes
twin BOV's on IC
Spearco IC, looking for 10 X 30 x 4.5 flowing top to bottom
Built 347
ET heads 11 degree 225cc
Cam who knows 230/230 116lsa
~9.0:1
Tube style manifolds 1.75" SS with merge collector
twin 3" downpipes
twin PT-61mm turbos .68 or .81????
3" pipes to the turbos
3" pipes to the IC
4" pipe from the IC to the TB
90mm TB
twin 38 wastegates externally vented 1.5" dump tubes
twin BOV's on IC
Spearco IC, looking for 10 X 30 x 4.5 flowing top to bottom
Originally Posted by Phil99vette
Here's the combo....
Built 347
ET heads 11 degree 225cc
Cam who knows 230/230 116lsa
~9.0:1
Tube style manifolds 1.75" SS with merge collector
twin 3" downpipes
twin PT-61mm turbos .68 or .81????
3" pipes to the turbos
3" pipes to the IC
4" pipe from the IC to the TB
90mm TB
twin 38 wastegates externally vented 1.5" dump tubes
twin BOV's on IC
Spearco IC, looking for 10 X 30 x 4.5 flowing top to bottom
Built 347
ET heads 11 degree 225cc
Cam who knows 230/230 116lsa
~9.0:1
Tube style manifolds 1.75" SS with merge collector
twin 3" downpipes
twin PT-61mm turbos .68 or .81????
3" pipes to the turbos
3" pipes to the IC
4" pipe from the IC to the TB
90mm TB
twin 38 wastegates externally vented 1.5" dump tubes
twin BOV's on IC
Spearco IC, looking for 10 X 30 x 4.5 flowing top to bottom
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I would drop compression ratio DOWN to about 8.0....
The T61's like running high boost..
At 8.0 CR you can run more boost and timing....
The .68 T4 turbine housing should be alright...
The 3" turbo inlet pipe is a good Idea...
However I would on the outlet side keep it small.. Basically what ever size the outlet is ~match it... Like on a 2" outlet compressor cover I'll use 2.25" piping max...
Coming out of the IC use a 3.5" pipe because 90mm~3.5 inches.
Smooth transisitions in diameter..... Also minimize the piping volume ... Like a head ports volume... Try to pick locations to mount and route things that keep the IC pipes as short and as straight as possible.
You were giving up alot of efficiency and spool with the other specs.
The T61's like running high boost..
At 8.0 CR you can run more boost and timing....
The .68 T4 turbine housing should be alright...
The 3" turbo inlet pipe is a good Idea...
However I would on the outlet side keep it small.. Basically what ever size the outlet is ~match it... Like on a 2" outlet compressor cover I'll use 2.25" piping max...
Coming out of the IC use a 3.5" pipe because 90mm~3.5 inches.
Smooth transisitions in diameter..... Also minimize the piping volume ... Like a head ports volume... Try to pick locations to mount and route things that keep the IC pipes as short and as straight as possible.
You were giving up alot of efficiency and spool with the other specs.
Last edited by V8_DSM_V8again; Dec 13, 2005 at 06:29 AM.
I would go with the .68 hot sides. Should go like whoa. 3" down pipes yes. 1.5 times the size of the ext. wheel, so 3" is appropriate. 3" to the intercooler and 4" to the tb would be exactly what I would do. Two turbosamrt 38mm units would work great.
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2" outlet turbo 2-2.25"
2.5" outlet turbo 2.5"
I still say 3.5" to the TB... A good molded silicone coupler will make the connection between the 3.5" and the outer diameter of the throttle body with minimal turbulence or uneccessary increases in area.
You dont want to choke it and you dont want to go so big you loose velocity and increase the spool point..
I have done a few FMIC's... Those rules of thumb work wonders.
Air to water has been the most wicked not just because of potential efficiency but because of much faster spool due to drastically reduced pipe length and much fewer bends..
2.5" outlet turbo 2.5"
I still say 3.5" to the TB... A good molded silicone coupler will make the connection between the 3.5" and the outer diameter of the throttle body with minimal turbulence or uneccessary increases in area.
You dont want to choke it and you dont want to go so big you loose velocity and increase the spool point..
I have done a few FMIC's... Those rules of thumb work wonders.
Air to water has been the most wicked not just because of potential efficiency but because of much faster spool due to drastically reduced pipe length and much fewer bends..
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From: Port Tobacco, MD
Sounds good, so 2.25" piping to the IC from each turbo and 3.5" to the TB with a 3.5" to 4" silicone reducer. 3" pipes from the filters to the turbos. Each side will get 38mm wastegates.
Phil
Phil
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Originally Posted by sr71
go with .68 ar's, Phil. mine make full boost at 3800.
SR71...
See what I'm up to this time?
I'm using twin 61's but with the T350 wheel and a .63 A/R T3 side...
I'm giving up about 50hp or so per turbo but given the application its worth it.
The idea is for a quick spool low & mid rpm truck motor..
Imagine 1k hp & Tq combined with 28" Front and 38" rear suspension travel...
[QUOTE=V8_DSM_V8again]I would drop compression ratio DOWN to about 8.0....
[QUOTE]
Doesnt 8.0 seem a tad low for a street car? Better to keep it higher so that your not bogging until you get into boost? Thats just what I was told.
CMC
[QUOTE]
Doesnt 8.0 seem a tad low for a street car? Better to keep it higher so that your not bogging until you get into boost? Thats just what I was told.
CMC
An 11:1 346ci could make 425rwhp easily.
So a 8:1 346ci could make that minus say 3-4% for each point in compression drop.
So if I use 3.5, that would mean that a 346ci could be making say 380rwhp.
I went 11.6 in 2000 with 375rwhp, with stock suspension and a small converter.
Trust me, 8:1 (I'm around there), has no bog. What's bog when you have a 4500 converter, and make over 700rwhp by 6000 rpms.
So a 8:1 346ci could make that minus say 3-4% for each point in compression drop.
So if I use 3.5, that would mean that a 346ci could be making say 380rwhp.
I went 11.6 in 2000 with 375rwhp, with stock suspension and a small converter.
Trust me, 8:1 (I'm around there), has no bog. What's bog when you have a 4500 converter, and make over 700rwhp by 6000 rpms.
