dragcamaro

is there a place i can find compressor maps for holset turbos, im doing a super budget setup and holsets are easy to find cheap and ive saw some good numbers and reliability, but id like to look at maps and see how they fit

if anyone has suggestions, im trying to find a good fit for 3 different possible setup, a twin or a single front mount, possibly a rear mount on a forged 370 with meth injection. running pump gas, stalled auto tranny, i havent decided if i want to go th400 or 4l80 yet though. it may end up being ran on a stock engine for a little while until i get the 370 built, it just depends.

thanks for any help, Mark

dragcamaro

the block is going to be O ringed as well, forgot to add that

slangegger

http://www.holset.co.uk/mainsite/files/index.htm

It can be hard to find maps for Holset turbos. They dont like to publish this information freely. Here are a few...

http://www.dieseltruckresource.com/d...-t255049.html?

dragcamaro

when selecting twins, what do i need to divide by two to get the right numbers, is it the pressure ratio or the mass flow? im considering running 2 hx35s

slangegger

If you run twins, you double the airflow lb/min. Pressure ratio is pounds of boost. To double this, you need to double the boost.

Here is a good write up about mapping.
http://www.mayfco.com/turbocal.htm

I thought about using HX35's for the same reasons as you. The problem I ran into is how large the frame is. In a hacked up drag car, you could prolly wedge 2 of them in there.

S13LSx

I'd run a HX55(72mm) single setup. Twin HX35's(56mm) would be nice but they are large frame turbos with very large compressor covers for a 56mm wheel. I would quess that a HX35 is about as big externally as a MP70. Here is a pick of the HX35 on my nissan 240.... It's a big turbo for a T3 flange....

dragcamaro

if i did twins i wasnt really worried about the size, id like to top mount them.

how much power is a hx55 good for?

slangegger

1050 CFM

Rule of thumb is 1.5 CFM per HP (approximate). To be more accurate, you need to map your combo.

HX55 is a (physically) LARGE turbo. I think there are better options.

darkhorizon

Most all holsets are big and heavy vs the flow they provide.. but they work and are unbreakable.

A HX55 should do north of 700whp without issues.

Roar

iTrader: (2)

I run a HX60 on a 383 LS1 at 12 psi (for now). No intercooler - just E85 and meth/water injection.

No dyno numbers but my "feeling" compared to my old 570 cid NA 866hp engine - I am guessing around the same HP number.

Going to crank it up to 17-18 psi for the coming season.

Not a lot of dynos available over here in Norway.....

slangegger

They are known to have weak shafts. Dont overspeed it, cause you prolly wont get away with it.

lazylongboarder

iTrader: (2)

I've seen the same thing, only after abusively high, sustained EGT's.

They are also known for having fantastic reliability when used for what they were designed for. Which is not sled pulling. Either way, to have a shaft break, IMO it was abused.