Help with 408 turbo selection
#1
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High on diesel fumes
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From: Phoenix, AZ
Help with 408 turbo selection
Looking for some opinions on turbo selection for my 408, mainly compressor size and a/r housing. I doubt I'll spin the motor up any higher than 6300 RPM. I think my cam runs out of steam right around there.
If I go with a turbonetics unit, I'm thinking the Super-T T76. Their matrix recommends the q-trim .96 a/r housing. About what RPM will this spool at?
I called a distributor for Garrett and asked his recommendation, and he told some that a GT42 would probably be about right. He said that a 1.15 a/r might be ok, but that it might generate a lot of heat if I'm hard on the gas towing up a long hill or something (which I will do). He recommended a 1.28 a/r housing, but said that it would probably spool around the 2500-2800 RPM range.
I'm confused as to why the turbonetics unit has so much smaller a/r housing. I'd like to see a little bit lower spool RPM than the 2500-2800 that the 1.28 Garrett a/r offers (especially since I am severely lacking in the low-end torque department due to my 7.0:1 DCR), but I'm concerned about heat and exhaust pressure like the guy said with the 1.15.
What do you guys recommend? Am I on the right track?
If I go with a turbonetics unit, I'm thinking the Super-T T76. Their matrix recommends the q-trim .96 a/r housing. About what RPM will this spool at?
I called a distributor for Garrett and asked his recommendation, and he told some that a GT42 would probably be about right. He said that a 1.15 a/r might be ok, but that it might generate a lot of heat if I'm hard on the gas towing up a long hill or something (which I will do). He recommended a 1.28 a/r housing, but said that it would probably spool around the 2500-2800 RPM range.
I'm confused as to why the turbonetics unit has so much smaller a/r housing. I'd like to see a little bit lower spool RPM than the 2500-2800 that the 1.28 Garrett a/r offers (especially since I am severely lacking in the low-end torque department due to my 7.0:1 DCR), but I'm concerned about heat and exhaust pressure like the guy said with the 1.15.
What do you guys recommend? Am I on the right track?
#3
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High on diesel fumes
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From: Phoenix, AZ
Towing is not the main goal. I want to put the truck in the 10's, but it's still going to be my daily driver. Mostly I want it to be fast and fun to drive, but it will see towing duty as a rig for a 6000 lb boat.
#4
mine has a ITS 80mm turbo on it right now and today made 615/615 but the tuning isn't done yet. should be upwards of 650-700rwhp when done. that too is on a 408.
have you contacted Jose at forcedinductions? That's who I'd call if I were doing it again. Also, I missed it, are you going T4 or T6?
have you contacted Jose at forcedinductions? That's who I'd call if I were doing it again. Also, I missed it, are you going T4 or T6?
#5
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High on diesel fumes
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From: Phoenix, AZ
I've been reading your nightmare threads about your truck - congrats on it finally running!
I'll call Jose tomorrow...I've had quite a few people recommend talking to him.
T4 or T6 - I know those are flange sizes, but that's about it Most of what I have seen is based on the T4 flange, but I haven't learned enough yet to know what difference it makes. Maybe that will be tomorrow's goal
I'll call Jose tomorrow...I've had quite a few people recommend talking to him.
T4 or T6 - I know those are flange sizes, but that's about it Most of what I have seen is based on the T4 flange, but I haven't learned enough yet to know what difference it makes. Maybe that will be tomorrow's goal
#6
Parish8 was running low 10's with his PT88 @ 16psi 'n 100shot assistance
http://www.precisionturbo.net
Give him a call buddy
peace
http://www.precisionturbo.net
Give him a call buddy
peace
#7
The t-6 flange is commonly known as the "thumper" flange, it is usually for all-out apps, the opening is much larger, you can get a blanket for t-6 flange turbos either. A t-4 flanged turbo will be easier to package and many more options.
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#11
Originally Posted by DanaliHD
mine has a ITS 80mm turbo on it right now and today made 615/615 but the tuning isn't done yet. should be upwards of 650-700rwhp when done. that too is on a 408.
have you contacted Jose at forcedinductions? That's who I'd call if I were doing it again. Also, I missed it, are you going T4 or T6?
have you contacted Jose at forcedinductions? That's who I'd call if I were doing it again. Also, I missed it, are you going T4 or T6?
#12
Originally Posted by 1slow01Z71
The t-6 flange is commonly known as the "thumper" flange, it is usually for all-out apps, the opening is much larger, you can get a blanket for t-6 flange turbos either. A t-4 flanged turbo will be easier to package and many more options.
That may be true but a T4 flanged unit on a 408ci motor is going to have alot of back pressure with that flange........
I have the S88 wich is a T6 flanged 88mm turbo with a 1.26 ar
sppols just fine with my 370..... i would imagine ven better with 38ci more...
Remember.. there a reason Parish went bigger..... she was just about out of steam..............
Kyle
#13
Originally Posted by NA$TY-TA
That may be true but a T4 flanged unit on a 408ci motor is going to have alot of back pressure with that flange........
I have the S88 wich is a T6 flanged 88mm turbo with a 1.26 ar
sppols just fine with my 370..... i would imagine ven better with 38ci more...
Remember.. there a reason Parish went bigger..... she was just about out of steam..............
Kyle
I have the S88 wich is a T6 flanged 88mm turbo with a 1.26 ar
sppols just fine with my 370..... i would imagine ven better with 38ci more...
Remember.. there a reason Parish went bigger..... she was just about out of steam..............
Kyle