twin turbo advice
 

hey everyone, so i decided to do a twin turbo set-up on my truck. 150hp injectors are ordered and i am using the stock turbo for my top turbo but have two options for the bottom one and was wondering if i could get your guys advice. the first one is an ht3b with a 26cm divided housing "not sure the compressor size". the second one is a s400 72/83/1.10. i know the ht3b is most commonly used for twins but i have heard from many people that its a little to big for the stock turbo. let me know what you guys think, thanks.

Im curious...will the stock holset hold up well with another turbo attached to it? Also how hard would it be to rig a piping setup?:pca1:

yea the stock turbo will hold up just fine, guys do twin set-ups all the time with them and make good power. the piping isn't that hard to mock up. if you know how to weld, thats just more money you will save. just look up kits and see what they all include. i decided to settle with the 72/96/1.32 turbo to use for twins. i priced up everything and it looks to be about $1600 including the bottom turbo, not bad for a twin setup

Sounds like it will be fun. I got bigger fish to fry before throwing an afterburner (Turbo) on my rig. Got to work on beefing up the trans. I was just wondering how the stocker held up to an additional turbo.

I would go for the 72/83/1.10.

it will spool much faster. ht3b can be used for twins, but it leaves no room for upgrade.

Then again, neither does the hx35 as a top turbo, but it should still make a decent top.

you may want larger injectors than 150s down the line...

I run S300/S400 twins (57/65/14 over 75/96/1.32) with 6x.013 injectors (240hp+ competition injectors)

i know bigger injectors would be better, but my goal is 550hp. i don't want to go too rediculous becuase this truck has to last me through collage and i want it to be reliable as possible . plus i tow with my truck back and forth to the track and don't want egt problem

with my setup I did 576hp/1285tq @ the rears...

as for towing:

Attachment 32003

pulled that over 3 mountain passes (stampede pass, snoqualmie pass, and tiger mtn) all 6% + grades and hauled 60mph+ no problem. Ran about 1050* on the pyro pulling the grades. any sustained temp 1200* and under is perfectly safe. even putting my foot into it WOT I couldn't get it to 1200*

when you tow heavy you turn the power down and let the injectors and turbos do the work. you don't crank the box up as high as it will go for DD and towing. I only turn it up when I want to accelerate ridiculously fast. Otherwise it stays set to timing only and my injectors make the power.

on injectors only I still make 380hp/850+tq @ the rears and that is still more power than a stock truck with a wiretap fueling box on it set to kill... only I have that kind of power ALL THE TIME, but my injection pump is not being pushed hard at all like it would be with the box turned up. Very reliable setup if you do the supporting mods (lift pump, gauges, valve springs, clutch, exhaust, turbos, intercooler boots, etc..)

thanks for your help "jigabop" the same day my injectors came in, my buddy bought them from me so now i can look at going bigger with the injectors. but another question i have is with the top turbo? i was thinking of buying a 60/68/.88 turbo for now because i think it should work good with the 75 sticks i have now. but what would be a good secondary turbo with that? i use my truck quiet a bit for towing and i leave the edge on level 2 when i tow, it doesn't get too hot now but i just want to be able to tow 7000 pounds without a problem.

60/68/.88 sounds very laggy for 75hp injectors..

.88 on that frame would be like a 16cm^2 housing (sounds like you are talking about an hx40 and they are laggy pigs)

a stock hx35 turbo is 56/60/12cm^2
a stock hy35 turbo is 56/58/9cm^2

my secondary turbo (top turbo) is a 57/65/14cm^2 (S300G)
and my primary turbo (bottom turbo) is a 75/96/1.32ar (S475)


my secondary would work great with your 75hp injectors. Don't underestimate that 57mm compressor inducer. it outflows hx compressors by quite a bit. BW uses extended tip compressor designs which are far more efficient and better flowing.



now if you want to try and go cheaper which is what it sounds like you are trying to do with the hx40 business...

you can go with a HE351CW (late 3rd gen wastegated turbo. Not to be confused with the 4th gen HE351VE variable geometry turbo) which IIRC is a 60/60/9cm^2

but don't let those specs fool you. their wastegate design in that turbo is far more efficient than the hx and hy design and they flow far more exhaust through them helping to better control drive pressure and heat with such a small turbine housing and turbine.

Makes a great secondary for twins as well. :tu:

thanks for all the advice! i have seen a couple he351 on craigslist for around $350 so i will defintly look into that. that way i wouldn't have to buy a t3-t4 adapter like i was going to do with the s300 so it should all work out good. thanks again for your help