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Discussion Starter · #1 · (Edited)
What in the hell is involved with cranking a 4bt up to those levels of power?

I'm thinking for my build:

40psi fuel pump
injection pump tweaking
POD/370 Injectors
HX52 turbo (16cm turbine/ 71mm compressor), possible duals
ARP stud kit
Balancing if needed?
Intercooler
4K/5K Spring
There has got to be a few other things I'm not thinking of...

I hear all of this talk about 450-500hp 4bt's but nobody who clarifies on making it to those power levels. This is NOT a DD.
 

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I'm new to 4bt's and have not heard anything on power like that from a 4bt! This should be a good thread. bounce
 

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Discussion Starter · #3 ·
I'm new to 4bt's and have not heard anything on power like that from a 4bt! This should be a good thread. bounce
Well a 4bt is literally 2/3's the motor of a 6bt, if there cranking out 800hp/1200lbft numbers there's no reason why we can't shell out 500hp/800lbft. Definitely not by Daily Driver Standards though.
 

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Main cap studs and a Girdle
Rod bolts replaced with ARPs
Head Oringd and studs installed.

Exhaust porting. cutting the intake off and porting out the intakes will help too but isnt necessay.

Camshaft with higher lift and duration values, matching valve springs you'll need to discuss with your grinder to get a good pattern for your application

370 injectors may or may not get you there. if you run 370's you'll be better off with the marine Ceramic coated pistons with teflon coated skirts. or the better oprion is get some EDM injectors and use domestic pistons and get them ceramic coated and teflon on the skirts. you have to remember the piston bowls need to match the injector spray pattern at those HP levels to really be efficient. marine injectors are ok but dont burn as well when matched to a domestic piston

Well Balanced engine assembly

Doing it with a Single would be a feat i think compounds would be alot more efficient at getting the job done.
I would probably start thinking about it with a S300 like the HTTB with a 60mm/12cm housing as the primary but the spool up on that may be a little too much as a primary on a 4bt the next option which i've had good success at the 450-490 hp range with a HX35/12 with the exhaust wastegate drilled out to blow off both ports. that would give you good flow and good spool up. match that to a HT3b/23 (most come with 26's) for your large compressor

I ran a large S300 as a secondary and the results were that my drive pressure ratio was off..... i thought i had it when we converted over to a S400 but cracked an oil return line on the lower turbo (because my bracket wasnt strong enough) and lost too much oil, the 4bt was a fun idea, got the motor for cheap like $600, honed it and ringed and then we did ours on a budget by passing the pistons and custom injectors. We used a marine head gasket and had blow off valves on the intake tubing..... would i do it again maybe, the thought has crossed my mind but the cost of doing it right is more than a 6bt so its hard for me to accept


that was 7 years ago so my memory is a little fuzzybut that will get you in there. tuning it is your responsibility as one combo can make 300hp running all the same parts and another with proper adjustments can clean up and make 450..... life span i know of three truck now running twins for more than 3 years and over 30k miles now on 4bts that they drive to the track and then race.......

the Ford recieved a 6BT two weeks later and used the HX35/14 with a S400 for a fantastic compound towing combo that dynod into the 567hp for 4 years and 300k miles towing GN most of its life. sold the truck last i know it just clicked 500k but is currently turning only 490hp towing a 5th wheel trailer around the country.
 

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Discussion Starter · #6 ·
Well the only dilemma that seems to be now is the injection pump. I would need to convert to a P7100. If I could get a 6bt one fairly cheap, could it still be applied to my 4bt (like block off 2 ports I suppose)?

Is there any way to apply a P7100 pump to the location where a VE pump was, or do I have to convert the cover?
 

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Is there any way to apply a P7100 pump to the location where a VE pump was, or do I have to convert the cover?
You need a different cover, gear, pump, injectors and lines
 

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Well the only dilemma that seems to be now is the injection pump. I would need to convert to a P7100. If I could get a 6bt one fairly cheap, could it still be applied to my 4bt (like block off 2 ports I suppose)?

Is there any way to apply a P7100 pump to the location where a VE pump was, or do I have to convert the cover?

you cannot block off lines or DV's on a P7100, about 30 seconds into things you'll find out that without a return line things will pop
 

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Well the only dilemma that seems to be now is the injection pump. I would need to convert to a P7100. If I could get a 6bt one fairly cheap, could it still be applied to my 4bt (like block off 2 ports I suppose)?

Is there any way to apply a P7100 pump to the location where a VE pump was, or do I have to convert the cover?
You'll be MUCH cheaper in the long run to find a P7100 equipped engine to begin with than to try to convert a VE engine. I've seen the injector lines alone go for $1100, when they could be found.
 

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injector lines

p pump injector lines can be bought from Cummins for about 85 dollars per line......not sure how or why anyone would pay 1100 for them, my custom lines were far less than that
 
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