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Compound turbos simple question.

1K views 2 replies 2 participants last post by  4everbtafan 
#1 · (Edited)
Do you need upgrades like fuel pin, and a gov spring to make everything work at minimum? Thanks in advance.
 
#2 ·
The upgrades will depend where you're headed with the power level. The fuel pin would probably be one of the last things. Governor spring is generally changed on a VE pump to 3200 RPM which helps with gear shifts. You don't run at that speed. The main changes are to the engine. Head studs would be highly recommended. If you boost is going north of 40 PSI you should O ring the head. A change to a larger oil pump and oil cooler are also recommended. A change to HD valve springs is recommended. Don't want to accidentally float a valve at the higher RPM. One size larger injectors are needed. A stock VE usually has 4x.012 units. Most go to 5x.012. That's about as large as a VE pump will feed. That will get you into the 300 HP area. Another thing you must consider is the transmission. If you run a manual unit you need a larger clutch to hold the power. Member Eggman an attest to that. A stock small block Ford clutch won't hold the extreme torque produced by the twin turbo engine. Same would be true of the stock GM Cummins flywheel/clutch assembly. Adjustment to injection pump fuel output and timing will be needed. Other options you might consider are changing the lift pump to piston type model for the VE. Dual boost gauges can be useful. Hewitt Instruments makes a dual reading gauge which is nice. These are high quality gauges often found in semi trucks. Not cheap though. Around $160. Also, need a gauge with higher reading than typical 30 PSI.
Gauge Measuring instrument Tool Auto part Circle

Don't forget the air intake. Be sure your air filter is up to the task of feeding twin turbos. Now if you get real serious have the exhaust manifold and turbo turbine housing coated with a high grade ceramic coating. That keeps the heat in the system and that heat is the energy that drives the turbos. You'd want a coating rated at least for 2000 deg F or more. The higher the better. The real super space age coatings are rated at around 6000 deg F. Definitely not cheap. Another extreme mod would be change to marine grade pistons. Those have a lower compression ratio, coated skirts, and dual keystone rings. Those came on the 250 HP 4bt. Engine starting in colder areas can be a bit harder due to the lower compression.
Gas Cylinder Service Font Auto part

This is just a general idea of possible mods and there could be other. Oh, be sure your intercooler is up to the task. Some super cheap ones may not hold 40 PSI or more.
 
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