Timinva

You do not need to move or get rid of your heat exchanger to run twins with a ht3b. There is plenty of room in there for both. I kept my cooler with both a 35/3b twins and now my 40/b2 twins. As far as I know piers twins are the only ones that require you to get rid of the cooler. Tim

Mike Holmen

Tim, how did you get that to work? Mines a pretty tight fit with the 5in exhaust. You must have the turbo down below the heat exchanger. You have any pics of the your sweet set-up. Hows the B2/40 combo working for ya? You get those mach 7's working?

Jambbii

I also got my heat exchanger to fit but it was very tight.

Jim Fulmer

i though i saw that Jim Fulmer did this set up and got around 700HP

674 on #2 and 706 with water! That was on Piers's dyno in Sept 03'

My old Twin setup stopped by the house the other day......odd to see it again since it was sold in the Fall of 03'

Jim

jwick

I run a 3B and a Dodzilla and made 505 on #2 with Don M 3's, got some 4's now, It really pulls hard, I can see about 60lbs of boost, I would like to go to a 26 undivided, I'm running a 22UD, at full boost I see almost 30lbs of boost between the bottom and the top charger, just wondering if the pn# of the exhaust housing will work on a Holeset HT3B, would a Garrett and Sch# work??

12valve

what was the dyno with the Hx35 and the 3B ? and maybe the 1/4 time and mph...

im still not sure where the b3 comes from. anobody here to explain that exactly to me...

thx

ddestruel

The HT3b is the charger that is used on Cummins 855 and N14 engines These engines are families of engines produced by cummins just like how our 5.9 is refered to as a 6bt, the N14 and 855's came in all sorts of aplications Kenworth, peterbilt frieght and shake, and also stationary equiptment with several different hp designations.

12valve

thanks, just needed to get thos facts straight...

guess i could do all the pipes, and welding etc,

just do i need some kinda external waste gate?
and or a bigger turbine housing on the stock hx35?
how about the oil intake? can i use a "Y" connection?

one54ton

Im with 12 valve, TTT.

Rhino

There is not need to y the intake, there is an extra output on top of the oil filter housing. I personally would not y the drain but guy do it. On an older 12v it is best to drill a hole and weld a bung on the drainpan.

If using an HX35 and external wastegate is the better way to go. It will bypass way more air than even a modified internal WG.

Diesel-Dan

I am dealing with a guy localy here that deals with these bigger turbos. He has access to good used turbos. I dont know yet what he is asking for them...but if any are looking for an HT3B....PM Me and ill see how many he has.....and if any have the "B" denotation.....he seemed to think that he had a few.....

12valve

cant wait to hear the price of one of those BIG turbos.
and where are they??? im in mexico.

Diesel-Dan

I got pics...but i cant post them for some reason!!!

HOHN

Now, that's funny right there. I guess reading every twins post you can find is now called "research." Guess I don't need to actually buy anything, eh..

Anyway, you can easily calculate the "paper" boost that a set of twins will make by looking at pressure ratios. Now, this ignores inefficiency, but it will give you a "max" value.

Say you have twins with a '35 and HT3B. You want to run both at 21psi so they're in the heart of the map.

What this means is that you are no longer feeding the '35 with just 14.7psi of atmospheric air pressure, you are feeding it (14.7+21psi) 35.7psi.

Now, you need to calculate the pressure ratio for your '35. At 21psi boost, you have (21+14.7) psia. Thus, you are turning 14.7psia into 35.7psia. So your pressure ratio is 35.7/14.7, or 2.43.

So your top charger is operating at a pressure ratio PR of 2.43. That means that when you feed it 35.7psia instead of 14.7psia, you will have (2.43*35.7)= 86.7psi absolute. Subtract your 14.7psi to convert to guage pressure, and you have 72psig.

So, running a big charger and small charger both at 21psi produces 72psi boost at discharge. Now this is just a "paper" value, and your real world value will fall below this by some amount.....

jh

600 Megawatts

Correct analysis brother Hohn. Lots of guys try to do it but dont add the 14.7 Psi properly, but you know..... But as you also know, you also need to factor in the density which is a strong function of temperature, so the effective density that the secondary compressor sees is quite a bit lower than that calculated using only pressure. The net effect, is that the total pressure ratio is lower, as you stated.

This is why I would be very interested in making room for an intercooler (since what we have on our trucks is an aftercooler ). With and intercooler and an aftercooler on twins, you could have a very efficient setup with a tiny top compressor, that would spool like crazy and be very easy on EGT's. I understand a few guys have this setup, but it took lots of fabbing with the bumper and moving the grill forward, getting rid of AC, etc etc


KP