T04 on 250 crossflow

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how much boost can a T04B porvide reliably on a 250? one turbo specialist tells me not to go over 14-16psi....
 
He's partly right. The turbo can go to well over that, but the device won't produce real hp without over speeding.

Bigger turbos are really the only way to go.

If you are on a budget like most sensible people, there is a compressor map which allows you to taylor the engine combo to the characteristics of the TO4 B turbo. It basically rules out running any more than 16 psi. Colin Townsend got 400 hp at the rear wheels with 28 psi and a TO4 in his propane 265 VG Valiant.

In the 80's, little split pules T03 60's like Commodore Turbos and AIT Turbos had could be worked to 360 hp, but they are really to small for drag racing.

The Sierra RS500's/Merkur Turbos ran T04's and then the HP race was on, way over 500 hp with ease.

The T04's, in A, S or B trim, are very good at giving 400 plus hp, but on a six, there is little point in having them go over the 12 psi level, especially if it is to see street duty.

Basically, bigger GT40 and Hybrid T45 and T66's are the go, as they have proper ball bearings and don't fry up as easily. The GT40 turbo is a stock XR6 Turbo bit. Its way over sized in the Falcon, and can take 500 hp without any alterations asside from putting forged pistons and good rods in the engine.
 
"The T04's, in A, S or B trim, are very good at giving 400 plus hp, but on a six, there is little point in having them go over the 12 psi level, especially if it is to see street duty."

why anything above 12? i was planning on running about 15 and i'll be driving it every day most likely
 
Detonation.

Everyone talks about how there Evo or STI is modded to do 18 psi, but there are a lot of broken Mitsi and Subaru engines around, too!

If you are able to do the modifications to lower the compression enough, say 7.5:1 using the 27 cc ACL pistons, and running the earlier pre XF (XD Alloy Head, XE Alloy Head II), and O ring the stock gasket or run an O ringed coper gasket, then you may be able to go up to 15 psi. The ignition needs to be reworked to have a boost retard or full solid state operation.


12 psi is safe. 16 is more of a worry.

These days, Evo 8 style intercoolers are common, so you'll need to run one to go beyound 12 psi.
 
thats exactly what ive done, its an xd alloy head with more meat taken out of the combustion chambers, o ringed block and copper head gasket, msd ignition with boost retard and forged pistons of unknown brand that came with the motor and were dished but have had the dish removed to make them flat tops, should be sweet then, i'll be running ultimate 98 anyway and if theres any hint of detonation ill be adding an octane booster.
 
Won't the extra boost also produce a fair amount more heat to get rid of? I could see that as a problem with a daily driver. Just a thought. Be nice to see some realistic "cost per PSI" figures for calculations, to find the crossover point suiting any application/budget best.

Adam.
 
yeah unfortunately i cant exactly intercool it..... but if it runs hot ill go water/methanol injection, if that doesnt work then god knows what
 
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