Engine/Transmission (1998.5 - 2002) Upgrade to twins, what do you think? PDR HX40 & HT3B Are Mach 4's too small?

[GOT-Torque]

I originally bought my PDR HX40 with twins in mind and I'm getting real close to ordering the rest of the kit. Now for the questions...



Will my Mach 4 injectors work okay with this setup, or will I have to go bigger.



How about the clutch? I assume my FE clutch should continue to hold up fine.



I am planning on stacks in the near future so the exhaust should already be 5" by the time the kit goes on.



How about max boost pressure? I installed ARP head studs a while ago, still running the stock head gasket. Does 45 lbs max boost sound reasonable?



Will the driveability change much? Any input is appreciated...



Thanks

 

[paulb]

I originally bought my PDR HX40 with twins in mind and I'm getting real close to ordering the rest of the kit. Now for the questions...



Will my Mach 4 injectors work okay with this setup, or will I have to go bigger.



How about the clutch? I assume my FE clutch should continue to hold up fine.



I am planning on stacks in the near future so the exhaust should already be 5" by the time the kit goes on.



How about max boost pressure? I installed ARP head studs a while ago, still running the stock head gasket. Does 45 lbs max boost sound reasonable?



Will the driveability change much? Any input is appreciated...



Thanks

Mach 4's with that setup should put you about 550hp. If you don't plan on o-ringing the head stay with the 4's. Bigger then that, and you will want to run more boost. 50 lbs is usually okay with studs, and a stock head gasket. Driveability... Spool will generally be slower then with the 40 as a single, however at a constant low rpm, air flow will be increased. The twins will pull harder at a higher rpm, and you should make about 50 more hp, then you are making now, with the same fuel. EGT's will be down.



Can't help you with the clutch...



Paul