what size twins for 346?
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what size twins for 346? Due to the weird size and shape of the engine compartment of my car (1985 Jaguar XJ6) I think I am going to need to go with a twin setup for my forged 346.
What size turbos do people usually use in twin setups? The engine compartment isn't that roomy so I would like to stick on the small side... I've seen people run as big as a T66 but I am pretty sure I don't want to go that big. What are some of the smaller sizes I can use?
I can only put 9.5" wheels on the back, so this car will be traction limited... and it's heavy to start with. The setup will be intercooled, with goals of around 650hp. I'm also open to using smaller turbo with a higher A/R on the turbine to push the torque curve a little higher in the RPM band... and then using a higher stall torque converter to pick up the slack.
What size turbos do people usually use in twin setups? The engine compartment isn't that roomy so I would like to stick on the small side... I've seen people run as big as a T66 but I am pretty sure I don't want to go that big. What are some of the smaller sizes I can use?
I can only put 9.5" wheels on the back, so this car will be traction limited... and it's heavy to start with. The setup will be intercooled, with goals of around 650hp. I'm also open to using smaller turbo with a higher A/R on the turbine to push the torque curve a little higher in the RPM band... and then using a higher stall torque converter to pick up the slack.
id say twin t44's might get you there. its an upgrade from the twins that come with the incon turbos(i think they were t36's, not sure though)
power wise, i think t44's will definately get you there. If not, always can go up to t60's...
power wise, i think t44's will definately get you there. If not, always can go up to t60's...
Since you are on a budget you should just plop on (2) Buick GN T3/T4 stock turbos. They max out around 400hpish. Used they can be purchased for $200 or less on turbobuick.com, turbobuicks.com, t6p.com and eBay in good working condition ready to install.
That is what I would do. Keep the RPM's down as your car will make plenty of power. Plan on running a 4L80E transmission.
(2) T66 turbos will take a while to spool and have the potential to make well over 1000hp. Plus your Shaguar rear end wouldn't last more than a few days.
-Mark
That is what I would do. Keep the RPM's down as your car will make plenty of power. Plan on running a 4L80E transmission.
(2) T66 turbos will take a while to spool and have the potential to make well over 1000hp. Plus your Shaguar rear end wouldn't last more than a few days.
-Mark
Originally Posted by 2000 Tran Zam
id say twin t44's might get you there. its an upgrade from the twins that come with the incon turbos(i think they were t36's, not sure though)
power wise, i think t44's will definately get you there. If not, always can go up to t60's...
power wise, i think t44's will definately get you there. If not, always can go up to t60's...
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Cool, so are all these T3/T4 turbos the same? A little background on them? Any water cooled bearing options?
Originally Posted by gnx7
Since you are on a budget you should just plop on (2) Buick GN T3/T4 stock turbos. They max out around 400hpish. Used they can be purchased for $200 or less on turbobuick.com, turbobuicks.com, t6p.com and eBay in good working condition ready to install.
That is what I would do. Keep the RPM's down as your car will make plenty of power. Plan on running a 4L80E transmission.
(2) T66 turbos will take a while to spool and have the potential to make well over 1000hp. Plus your Shaguar rear end wouldn't last more than a few days.
-Mark
That is what I would do. Keep the RPM's down as your car will make plenty of power. Plan on running a 4L80E transmission.
(2) T66 turbos will take a while to spool and have the potential to make well over 1000hp. Plus your Shaguar rear end wouldn't last more than a few days.
-Mark
The GN I believe is the only one with the T3/T4 hybrid and it is not water cooled. SVO/Tbird's have smaller turbos and are water cooled rated at around 300hp flywheel.
I wouldn't worry about it not being water cooled. You can get a turbo timer if you are that worried. The '86-87 GN turbos are 3 bolt and would take a round pipe (3" approx) to feed the turbine housing. Moving forward if you needed larger turbos any 3 bolt style turbo will work fine and bolt up to your intercooler piping and downpipes.
John Meaney (father of DFI) used 3 bolt turbos on his twin turbo C4 street car and went 160mph in the 1/4 with them. They were PTE-52's I believe..... They make a T-76 in 3 bolt as well..... if you were crazy enuf.
Meaning you don't need 4 bolt turbos to make power. They do make slightly more power and flow better.... but 3 bolts aren't that far behind.
I wouldn't worry about it not being water cooled. You can get a turbo timer if you are that worried. The '86-87 GN turbos are 3 bolt and would take a round pipe (3" approx) to feed the turbine housing. Moving forward if you needed larger turbos any 3 bolt style turbo will work fine and bolt up to your intercooler piping and downpipes.
John Meaney (father of DFI) used 3 bolt turbos on his twin turbo C4 street car and went 160mph in the 1/4 with them. They were PTE-52's I believe..... They make a T-76 in 3 bolt as well..... if you were crazy enuf.
Meaning you don't need 4 bolt turbos to make power. They do make slightly more power and flow better.... but 3 bolts aren't that far behind.
