LQ4 turbo reccomendations
Vehicle:
- 1990 RCSB Silverado
- LQ4 with 317 heads
- T56 & LS7 clutch
- 14 bolt SF rear 4.88 gears and TruTrac
- Walbro 255 hotwired
I'd like to make a solid 600RWHP maybe eventually kick it up to 700 at a later date. I'll be fabbing up most of the turbo system myself once I can get some direction as to selecting the proper turbo.... Planning on using stock iron manifolds. I have 3 manifolds to choose from also, truck, LS1 and LS2 manifolds.. I'm looking at a single 80mm turbo..... Probably a Borg Warner. What I really need help on beyond that though is what A/R? What flange? T4? T6?
My only changes planned for the engine itself are LS2 head gaskets, ARP head bolts, and a cam that works well with the turbo. Planning on leaving the stock shortblock untouched. Truck is a street truck, will be put back into service as a DD once it's on the road. Not really interested in hitting the track more than occasionally if even that, just a real strong street machine.
Those 4.88 gears have to go, get something in the 3.42-3.73 range.
Last edited by MY_2K_Z; Jul 24, 2016 at 09:24 PM.
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I guess for a vague response I would like to minimize turbo lag but I dont have the requisite experience to really figure that out like I would like to.
Loud and clear on the gears. I have a set of 3.42 gears and also another 14 bsf housing to rob gears from (also 3.42 would be my guess.) I had to slip the clutch a lot with the old 3.08 10 bolt I had with the 300FWHP SBC it used to have when the T56 first went in. The 4.88s were great comparatively.
Tires are 29 overall diameter. With the old N/A mild SBC it would move out really well in 1st 4th. It is a big heavy truck with tall tires and the MN6 gear spread.
What fuel pump would be recommended if the Walbro 255 wont do it? Im aware of the LS7 clutch being rated significantly less than my goal and the T56 being a good candidate for some high HP help.
Having said that, I just converted this T56 from LTx to LSx and everything looks great, Im just gonna run it till it explodes and then rebuild it or swap in my other T56.
With the 29 tires I will be reusing, the old ~300FWHP SBC trim and T56 4.88 it would turn about 1979 RPM in 6th at 70 mph.
Appreciate the input guys. Definitely helpful for me.
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How would you compare that turbo to say, a Borg unit like this one?
https://www.summitracing.com/parts/b...qwzBoCGM7w_wcB
Glenn ***
Sales Tech
www.bmrsuspension.com
813.986.9302

Find a Quality alignment shop near you!
Glenn ***
Sales Tech
www.bmrsuspension.com
813.986.9302

Find a Quality alignment shop near you!
You got any pics of that truck project?? I'd like to see it. And forgive my ignorance but what does SBE mean?
Also, could you guys weigh in on intercoolers, BOVs and wastegates, like which ones would be good buys? I've been looking around, mainly on fleabay but again, I'm overwhelmed with possibilities and choices.
What intercooler setup should I go with, does anything here stick out to anybody?
http://www.ebay.com/sch/i.html?_from...ER&_sacat=6000
It's nothing crazy, but she still cleans up nice after 265k miles
. Tired old 305 isn't cutting it anymore haha. Got a good deal on the 6.0 so I decided why not. Always dreamed of doing this with this truck so I decided to stop dreaming and start doing


It starts really getting fun next week when more parts get here so I will be taking more pics then
Glenn ***
Sales Tech
www.bmrsuspension.com
813.986.9302

Find a Quality alignment shop near you!









