mirage2991

iTrader: (1)

hey guys, I've been reading a lot of stuff on this forum and the net, noticeably the "big bang theory" from car craft (4.8 and their later 5.3) and my goal is 700-750 crank. I believe I can get there with the stock 706 heads (no port work) and a descent cam, with twin turbos (but perhaps I can even get it done with a single turbo) intercooled. The money "saved" by leaving the heads unported would allow me to put it towards a nice aftermarket EFI set up.
This motor will power my new project, a 68 vette convertible pro street hotrod. It will never see the track, so I'm not chasing ET, just a nice fun hotrod to putts around on sunny days.
thoughts?

93camaro_zzz

iTrader: (13)

Hello, welcome to the forum! Try searching for your topic up top, because this has been covered a lot of times, and you will find more than enough info.

Busted67

iTrader: (1)

A single 72-76mm turbo or 55-60mm twins will get to your goal and then some. Which ever packages easer and stays within your budget.Don't over turbo a street car.

JoeNova

Gen 3 4.8 or gen 4 anything will give you 750 flywheel fairly reliably on a stock long block and very mild cam.

Borg Warner S475 with 83mm turbine will be loads of fun on the street and still pull hard up top on a 4.8/5.3 at 750 hp.

mirage2991

iTrader: (1)

Thanks guys, yup definitely used the search button, probably to my own demise and was a little confused on what I truly needed

mirage2991

iTrader: (1)

Coming back with what I think should work, hope someone can confirm I'm on the right track (from reading pages and pages of turbo set up online)
I've bought the cam now (tick stage 3 turbo 5.3), from what I've been reading I believe a pair of On3 70mm with .68AR (exht side) should work for my goal (700 crank)

Cold Side

Compressor Wheel 61mm
.70 a/r
4” Inlet and 2.5” Compressor Outlet
Inducer- 70mm
Exducer- 99mm
Exhaust Side

Exhaust Housing T-4 Flange
.68 / .81 / or .96 ar Exhaust Housing
3.0″ Vband outlet
Inducer- 74.5mm
Exducer- 65mm

BUT, I may have a situation running twins and finding room on both side to run down pipes, so I need to be prepared to run a single turbo, in which case I'm thinking the On3 78mm.

Cold Side:

Compressor Wheel 78mm

.80 a/r

4” Inlet and 2.5” Compressor Outlet

Inducer- 78mm

Exhaust Side:

Exhaust Housing T-4 Flange

.96 ar Exhaust Housing

3.0″ Vband outlet

Exducer- 76mm


…and who doesn't like pictures of project? :

nofxgivn

iTrader: (1)

we run a bone stock 5.3 with turbo cam and springs with the cheep on 3 7875 and through a stock junk 4l60e and a stock 10 bolt rear all in a full interior full weight 3700lb Camaro we have made 700 whp on a single with 14lbs.super simple.dont over think it for that kind of power.keep in mind the DA here is 6500-7000 ft of air.enjoy

mkvamso

iTrader: (2)

Twin 70s will be way more than enough
I'm using cheap cxracing gt35s making mid 700s to the tire

mirage2991

iTrader: (1)

ok cool, thanks guys

kwrench61

iTrader: (1)

Using CX racing 80mm stg3 ball bearing turbo with 1.15 a/r on 6.0 LQ4. I should be 850-900 at 15# boost.

DavidBoren

Keep it simple. The more simple the plan, the more likely it will see completion.

The single turbo will give you what you are looking for, and will do so with fewer parts.

With the money you save by going with a single turbo, you can port those heads... Because you should never neglect the heads.

mirage2991

iTrader: (1)

yeah I agree with you, though the reason for twins is the "bling" effect, because it's a hotrod, not looking for ultimate drag performance…but yes would save some money for sure going single.

DavidBoren

Personally, I don't find there to be any additional bling factor with twins, UNLESS they are mirrored/symmetrical.

Symmetrical snails are pure sex.

But given that you mentioned saving money, that means you are a mere mortal, like the rest of us, and cannot afford Nelson's symmetrical turbos.

So...

My vote is for nice sized single. I think it will do you well.