davesengineshop

So I decided to turbo charge my 83 Z-28. Gonna have a 400 SBC in it since my 305 is pretty much junk. At least for a race motor.It probably would be an ok street motor for a few miles. But any way shooting for 11.10 in the 1/4. Right now the car runs 14.80's in good air, so I need a bunch of power. I am shooting for around 3200 LBS with me in it and maybe a little poop in my pants(from going that fast) I have an Edelbrock performer cam that i plan to use. I have 3.23 gears and will be running a th350 transmission. Also have to use a carburetor since EFI isnt an option due to budjet issues. The turbo I have is off of a volvo XC70 and is in good shape. I belive the stock wastegate opens at 9.5 LBS of boost. Since I am new to turbocharging I am going to use this thread for all the stupid questions that I will have.
Here are a few
1)Should I run the turbo off of one side of the engine or should I pipe all 8 cylinder thru it?
2)What mods do I have to make to the carburetor to make it funtion correctly with boost.
3) How much boost do you think I will need To run low 11's

Here is a list of planned engine mods:
1) Bowl blend intake ports, keep the 1.94 intake valve but get stainless ones with a under cut stem to improve flow, then back cut the face also for a slight increase in flow
2) Fully port the exhaust, up the valve size to 1.60" , stainless under cut valves again with a back cut
3) I have a Weiand x-celerator intake, but thinking about a Victor JR
4) Probably go with 1 3/4" headers(built by me)
5) windage screen, pan baffle and crank scraper
6) MSD ignition system
7) 140 GPH electric fuel pump with a mallory adjustable bypass regulator, 1/2" Feed line and 3/8" return
...and possibly a few more

So let me know thoughts opinions and answeres to my questions THANKS

daverr

iTrader: (1)

that turbo will not work its for a volvo with a 2.something liter not a 6.6ish liter v8 engine. force induction works best with EFI. Carbs imo are good for na/nitrous/6-71 like superchargers engines.

On a single turbo setup u need to run all 8 cylinder exhaust to it.like this

Street Lethal

iTrader: (16)

^ .... umm, would you like some engine with that turbo Dave lol?

built91Z28

LOL, the understatment of the day.

brandoz28

iTrader: (1)

a few things to address....

your plans for headers are WAY too large, 1 5/8 is all the bigger i would go for a turbo motor that mild, otherwise you're going to lose all of the exhaust velocity you need to spin it.


carb mods are going to be completely different depending on what carb you plan on using

Drac0nic

Google hanger18 for the carb mods if you're doing a DP. You don't need a huge one on these keep in mind there have been ppl that generated 1200hp with a 650 CFM. An oversized carb can be bad too because it can interfere with the signal. You can do an Edelbrock as well the mods are out there. I'd check theturboforums.com's carb section. Those guys do amazing stuff with em. The Volvo turbo is way wrong you need something in twin T4s or a T6. For your power you might be able to do a T76 but that would be hugely pushing it.

davesengineshop

Ok so the headers being smaller will save some money. What kinda mods will the carb need.

Daverr I realize the turbo is really small. since it is the only one I have/can afford. what problems will I run into running a turbo that small???

davesengineshop

Thanks for the info. I will look into the edelbrock since that is what is coming with the motor.

daverr

iTrader: (1)

you will have the performance of a volvo.

sure why not

junkcltr

iTrader: (1)

Even with twins of that size they are way too small. With one you will over-speed it and end up sending turbo parts through your engine. It isn't a matter of it won't work good / make HP. It is a matter of it will come apart. An engine has an RPM range and so doesn't a turbo. Over-rev and bad things happen.
If you can't afford a more appropriate turbo (but can afford to make headers??) then I would hold off on the project.......or get priorities in order.

davesengineshop

So basicly I need a bigger turbo(s) or Stick with N/A

Drac0nic

That will cost you power because it will be so restrictive. I'd consider a pair of GN turbos minimal for this project

ED:and even those would be grossly under sized.

Orr89RocZ

iTrader: (20)

I got a mild 401 based motor. By mild, i mean i'd run the cam and heads on a 355 let alone stick them on a big 400 inch motor. Twin T4 60mm units from Master Power. Works well. 8 psi will get you into the 10's as long as you have good heads, medium cam. Doesnt take much boost to make a 400 move a 3450lb car. 12 psi is over 650whp

You can do it on motor fairly easily too. All up to you.

junkcltr

iTrader: (1)

You have twin 60mm T4s. He was thinking of putting a single 37mm T3 on his 400ci. Probably would make some decent PSI at idle.

I would just N/A it if the cost of a turbo is too high. You have a lot of choices for a turbo on a gas 400ci from a diesel app.

davesengineshop

Whats the smallest turbo I can get away with and make enough power to run 11 flat

Orr89RocZ

iTrader: (20)

Dont know much on the factory diesel turbos but they are designed for low rpm motors and with your setup it may work out. For a low rpm 400ci motor say to 5500 rpms, 6 psi will get you 450whp easily assuming that 400 can make 400hp on motor alone, which is easy since 1 hp per 1 cubic inch is common. 450whp in a standard weight turdgen can get 11 flats

Its just that at that low boost, to get on to an efficient compressor map, its difficult because pressure ratio is sooo low.

brandoz28

iTrader: (1)

i would look into a master power t76 and build a single turbo, i've always liked a single a little better than twins personally

ZZ3Astro

You could probably make one of the Ebay GT45's work for that kind of horsepower and stay on the $300ish budget. I've had great luck with my Ebay turbo so far, but it's only good for about 450hp (T70).