What are the highest boost pressures youve ever heard of in a diesel? What kind of pressure would twins build?

Mike

heard of 120 psi. Seen 65. Twins seem to build between 50-70 depending mainly on wastegate and owner. You can run them higher

-ben

185+ in a pulling tractor with4 turbos 1st one is the size of a milk crate i've seen tractor trailers pull 65. pickup I seen 38 on a 24v cummins stock turbo pyro temps were going through the roof fast though

I've seen twins at 70, and a mild single at 45. Mine runs 38.

Ask Lance what his was at when the rig went :nuke: :laughing: :laughing:

Ask Lance what his was at when the rig went :nuke: :laughing: :laughing:


Harsh Eric, harsh. :laughing: :laughing:

Ask Lance what his was at when the rig went :nuke: :laughing: :laughing:

Was that before or after he installed the twins? I know he burned it down before the twins...

Mike

A couple of the guys I've talked to at the diesel drags were running around 120-130 on a 5.9 cummins with huge twins.

45psi with my puny single on the ol Cummins, Ive heard of 120 on a twin turbo'd Cummins.

Piers Street Twins are around 90PSI and make upto 900 hp on a properly built motor. Heard of people running well over 100 at drag races and sled pulls..never actually seen their gauges though..

Stock truck with just gauges, and a straight pipe, my 04.5 CTD600 has hit a max of 29 psi.
Scott

My Powerstoke maxes at 33psi with the stock turbo. Heard of some Powerstroke guys running in the 90psi range with custom turbos. Seen 55 on a single turbo Powerstroke.

I know you were looking for CTD info, but I wanted to tell you what the other camp is doing. Maybe someday we will get a realistic twin setup for a Powerstroke.

Mine's 48 on a big single and I've heard of 120 from the boys with too much money :flipoff2:

Past issue of Diesel Power Magazine had a sled pull truck running 190PSI with twins on a 5.9L.
I have seen 80 in Caterpillar C15 Acert engine (twin turbos), in a T800 Kenworth. But I was full throttle and a heavy foot on the brakes to make that happen:laughing: :D

Boost PSI is only one part of the equation.. You can have a real small turbo (HX35 for example) making 40 PSI of boost. That is not going to do much for power compared to say 28 to 30 PSI of boost with a larger turbo since you out of the turbo efficiency range. If you're making 60+ PSI boost with a compound turbo, then you're making some serious power.

Boost PSI is only one part of the equation.. You can have a real small turbo (HX35 for example) making 40 PSI of boost. That is not going to do much for power compared to say 28 to 30 PSI of boost with a larger turbo since you out of the turbo efficiency range. If you're making 60+ PSI boost with a compound turbo, then you're making some serious power.

I wasnt actually thinking about doing much more than I have currently. I was just on Cumminsracing.com and saw that their dragster was pushing over 100psi on the track. I was shocked. Then a couple of guys at work said they have heard of 130psi. I was just curious of what kinda of pressures diesels were capable of.
I just got to thinking, I wonder what kind of cylinder pressure you would have with 150+ lbs of boost in the intake.

Mike

I remember being impressed when looking over the Edge "drag truck" (the little dakota looking drag racer) last year at SEMA.....




it's boost gauge went to like 250 psi :eek: :eek: :eek:

it's boost gauge went to like 250 psi :eek: :eek: :eek:
Thats about what all the pulling tractors will do.

it's boost gauge went to like 250 psi :eek: :eek: :eek:
Thats about what all the pulling tractors will do.

I've personally had my 300k miles 12v CTD up to around 36/37 :eek:

You can have a real small turbo (HX35 for example) making 40 PSI of boost. That is not going to do much for power compared to say 28 to 30 PSI of boost with a larger turbo since you out of the turbo efficiency range. If you're making 60+ PSI boost with a compound turbo, then you're making some serious power.

bravo. High boost numbers dont mean high hp/torque. A stock psd turbo is only efficient up to around 25 psi. Sure you can throw 35 or 50 psi at it but all its doing is kickin its own ass.

High boost numbers dont mean high hp/torque.
It sure does, as long as you can keep up with the fuel demand

It sure does, as long as you can keep up with the fuel demand

What he said. Just because a turbo is out of it's efficiency range doesn't mean it isn't making anymore power. If you've got the same exact engine, heads, intake and exhaust piping and go from 35psi on an hx35 to 35psi on an hx40, the peak numbers are going to look the same. Holsets love high boost though, and since holset doesn't realease flow charts...noone knows their efficiency range anyway.:flipoff2:

My 05 CTD will hit 32psi stock. The stock turbos can push out about 40psi with a proper box.

If you guys wanna talk about efficiency, talk about drive pressure/boost pressure ratio's.
Discuss...

My twin'd CTD is gated to 55psi to keep the headgasket intact (I hope).