What makes you pick a single or twin setup?
 

im torn, ive been reading for the past few weeks, ive read numerous posts about singles and twins. How do you guys pick? i cant decide which route to go. Seems twins is the cleaner easier piping route, but Hooker also makes a nice turbo manifold crossover setup for twins that looks very stout. I have an LQ4 4l80 combo going into a 87 crew cab long bed dually. ill never tow with the truck, just a weekend cruiser with the old lady. its not a race car but id like to make some power, looking for more low end power rather than making it sing. ive read alot of twin gt45 setups and alot of single borg 400 framed builds.

thanks

Fitment / cost

dead on. Sometimes it is easier to fit say 2 7065s vs 1 s480. But you'll also need 2 gates, double plumbing, and you gotta merge the cold side somehow. If you can fit a single it's the way to go imo

I would just pick up a truck log manifold and would run a single small s475 , will spool quick and be fun in a heavy setup since the boost/torque will come on early . Twin GT45s will be dogs and especially for a street cruiser .The S475 will support close to 750 to the wheels and should be more than enough for street use.

Many with singles run 2 gates, you need to find room for a much larger turbo, sort crossover pipes etc etc

Really neither is much different than the other. Just do whatever is easiest to fit on your car AND easiest for maintenance thereafter.

Some setups with crazy exhaust manifolds were you cant get access to plugs, or wires too close to hot stuff etc etc are just daft. Make life easy for yourself where possible.

I would be interested to see how many have gone through the calculations to determine optimum size and configuration prior to installing something or just bought one or two turbos based on internet chat and just stuck them on there.

with single you need manifolds, a crossover and turbine combination that will flow the volume of air that's going to be produced by your combo. cubes, boost, power, fuel type etc etc all come into that. generally that's relatively large and therefore will have a bit of lag. you cant expect a turbo that comes on boost at 3500RPM with (for example 400cubes, 20psi boost) to efficiently flow through the exhaust system efficiently at 7000RPM. however a turbo that comes on boost at 4800RPM most likely will flow efficiently to 7000RPM. as a rough example... T4 76/75 precision on that combo would likely represent something that would be on around 3500RPM and a T6 S488 with 110/96 turbine would likely represent the latter example.


with twins you only need to flow half that amount through each and as such the turbine can be smaller and less laggy. but it is more expensive.

when you're talking big cube, massive power one turbo may not physically flow enough air for the goals and no choice but twins is sensible. but that's at 2500hp plus and 500+cubes

Real world experience is better than some calculations based on hopefully correct info, for the variable that is "optimum"

i agree.. i like hearing what others have done and what works. a book can tell you how it should or may work.. but thats not always the case. Hence field engineers who sometimes may have never done the actual field work.

whats considered a small single 475? 83/87? i would think id want the 1.1 a/r to help with spooling too.

yeah not me, i got a basically stock lq4 not a 500 inch race motor. Hooker makes a nice single crossover setup designed for c/10s so that would make my hot side very easy.

if its a six liter, get the big turbine s475 or s480. they light off plenty fast with the bigger cubes

What is small depends on what you need it for or expect it to do for you.

drivability, its going to be a weekend cruiser. going in a big heavy truck that has to potential to haul 6 people in it. i want it to light up as low as it can rather than having to wind it up to make the power. im not after a certain HP number but obviously more is better, just thinking going the turbo route is the best bang for buck on making some power.

I built mine (twins) on purely the bragging rights to say "twin turbo".. Lol Sounds trivial but it just sounds cooler then single turbo IMO haha But it was much more expensive in the long run for sure.

The fastest cars are single. Plus way less piping. No brainer for me.

i dont think theres nothing fast about an 87 crew cab long bed dually on 24 rims lol

Sounds perfectly reasonable, a good 475, biggish turbine would work well. He could go smaller but a big heavy truck should have plenty of load against it so that would help spool anyway

Sounds like a China 7875 will suit you just fine. Not looking for speed, need fast spool, not looking to wind it up......yup....7875.

like this VS Racing piece?
https://www.ebay.com/itm/VS-RACING-7...frcectupt=true