Hi guys .. I have 05 sierra 1 cab ... i'll Build a twin turbo on it & upgrade all internal parts , crank,rods,pistons .. etc.

the stock engine will remove it so i can choose a bigger C.I block

Which block do you suggest for daily drive & less issues

1- 427 ci chevy .

2- 496 ci gmc .

and why ?

If you have any idea please inform .

thanks in advance .

 

Well to start with I would talk to race engine builders. I don't think anybody on this forum has a 1000 hp engine. When you are talking about that kind of HP that is high $ and you want only the best info. Good luck and let us know how it works out.

 

Well thank you for reply

 

if it's any help, I'm working on a 67 camaro project with a slightly smaller goal of 800hp.

already having a 427 bbc and wanting more than 600 naturally asperated hp, I was directed to twin holset hx35's off the cummings 5.9L with 8-10 lbs. of boost on pump gas for a 800hp goal with full boost around 2500 rpm's; with stock forged internals and stock rectangle port heads. cam and compression change of course.

so maybe that bigger displacement you mentioned ( 496 ), you could get 1000. and if not, beef up internals and octane, and turn up the boost.

 

For 1000HP you need to have a big engine that is able to expel a ton of exhaust gasses to turn big enough twins, to give it enough air.

I would start with a 496 or 502. 502 would be your best bet. You will also need to make sure your pistons are FORGED! Cast and Hyper are not good ideas in turbo applications. As hell as H-Beam rods to hold up to the stress

On top of that Fuel Injection is the way to go. Blow thru carbs get me confused and I understand EFI better then them. You will need a computer setup which I am a Megasquirt fan, but over on FSB are some guys who are running different Aftermarket ECU's.

With that in place you will need to or find somebody who can figure out what size injectors you will need for your RPM range. Turbos are going to be a bit tricky but HX35's or even the HX40's off 6CT's they will be able to move enough air. And with that... a HX35/40 Hybrid may be better cause it would have the spooling characteristics of a HX35 but with the flow of a HX40, and your not going to push no more then 15PSI I would guess so it would be safe (If we were talking about a Cummins 30 PSI is max on a hybrid)

You can buy premade twin turbo manifolds for BBC's or make/have made your own.

From there you also have exhaust routing, and air side plumbing. I would run a Water-to-air intercoolers, these are more efficient and take up less space then traditional ricer/diesel front mount intercoolers.

You will also need to plumb in wastegates and blow off valves. Wastegates so you do not over spool your turbos and make them fly into orbit and into your engine and blow off valves so that when you let your foot off the go fast pedal your system can relieve its self of the pressure built up and not pop anything, like boots!

Also you may want to think about a water/meth system to keep detenation low as well as a ignition system that will help in tuning your system like a MSD 6 BTM (Boost Timing Master)

Also talking about ignition you dont want to use HEI, you want to run a setup with a external coil, and colder plugs too.

Also there are some great manuals on turbocharging, which I suggest you get and read read read! Turboing is a long, expensive path, and if not done correctly will cause a bunch of headache.

 

well thank you cowboy

what is your opinion about kenne bell 4.2L and which turbo brand you suggest

 

Never messed with Bell Superchargers, I prefer a centrifugal supercharger.

All turbos I have messed with are on diesels, mainly Powerstrokes and Cummins. THought I do recommend

The Boost Lab

they are intelligent people who know there turbos. I trust Garret and Turbonetics turbos for gas engines

For reliability and to help against coking use a turbo with ball bearings and has a water cooled center section

Coking is when you dont allow the turbo to cool and it cooks the oil into a white powder which looks like, you guessed it! COCAINE! (Hence coke)

There have been thoughts and talk about experimenting with turbo drains that drain into a 'Oil Box' this oil box then drains threw a big oil cooler then into the crankcase. This helps cool the oil so there is not excessive heat build up and break down of the oil.

Also in the fuel department there is two stage fuel injection which uses two sets of injectors for one cylinder, it kick a the second set of injectors on at a certain RPM.