Have some newbie turbo questions...

[NorcalZ71]

Hey all,
So short summary: Me and my dad are planning to build up a new engine for my truck this winter (94 z71 ext cab) and i am throwing around the idea of running a turbo/twin turbo setup on it. Thing is, i know very very very very little about turbo systems, so i need to educate myself. I was directed here by someone over at Fullsizechevy.com, they said you guys know your stuff when it comes to turbos.

Loose specs for the engine call for either a stock 350 .030" over w/ a stroker kit for a 383, or an LT1 with the same treatment. Aftermarket heads, possibly some porting (my dads friend is REAL good at porting, he does a lot of heads for drag racing), headers, cam, new everything etc etc. If going with a 350 base, it will either be TBI or hopefully TPI if i can get my hands on the stuff and make it legal in CA. If using the LT1 then we will stick with that intake. Also if you guys have a better idea there let me know, the truck is a 4x4 and is lifted (soon to be more) so low end grunt is my goal, and lots of it.

So i suppose my first question is, is a turbo or twin turbo setup a good choice for my application? I don't really mind cost that much, this is a semi long term project for us. If yes, would a single or twin setup be better, and if twin, what about a sequential system? What size turbo(s) would i be looking at needing, and what kind of costs would be involved? Is there anywhere i can read up more about this stuff so i can get a better grasp on what we're trying to do? Also, what about tuning?

We are loosely designing this engine based off the specs of an engine a friend of my dads just completed. It dyno'd 360 hp and 460 ft lbs (its a 383, TBI, edelbrock heads and custom ground cam thats all i remember off the top of my head). Anyway, that thing is currently getting about 20 mpg in his heavy, 4x4 88 suburban. He also threw some serious $$ into the R&D in that thing, theres a few other bells and whistles as well. If he is pulling 360/460 NA, what would be reasonable numbers on boost? How would it affect driveability and mileage?

Sorry that was a long post, just trying to cover as many bases as possible, thanks for your time

 

[turbo2nr]

I think entering the X prize would be easier, racing to outer space. This sounds like a very extensive project. Why do you want to turbo a 4x4? Why not just a huge motor? It will be cheaper, and low grunt will be no problem. Check out some books on turbocharging, like "turbochargers" by HP books, or MAX Boost. I wonder if "Banks" is still doing the twin turbo chevy thing?
Adding a turbo to a non-turbo motor is a BIG job. Oil requirements, cam choice is important, compression ratio needs to come down. vac lines all need to be thought out, what about a brake system? Vac assisted brakes do not work too good with a turbo. Need a stand alone computer, good background on tuning, many hours of tuning and testing, makes me tired just thinking about it. As far as matching one or two turbos to your requirements, many things need to be considered. What type of torque do you want? What rpm? What about your fuel you plan on running? Figure out what compression ratio, and what size motor you are going to use. The book "turbochargers" has a good section on matching turbos. Exaust/headers will most likely be a custom job. Good luck and have fun!

 

[NorcalZ71]

Thanks mate, i figured it would be a pretty substantial job, but I like to be different sometimes and it seems like it could turn some good results. My dad has a pretty extensive background in engines, suspension, racing you name it, I'm just trying to brush up on my end. I don't know why, the small block just appeal to me more. I'm trying to achieve a killer power-MPG-driveability ratio. Hard I'm sure but I'm up for it. I will have to check out that book, hopefully my school library has it. As far as tuning goes, I've been reading up a lot on it (but still confused as heck) and I will have access to a dyno to help out. Thanks for the reply man, I;m sure I'll find many more questions shortly