Single Rear mounted turbo... Stock motor 100k miles?
Hi all,
New to the corvette world, found an 86 coupe with automatic tranny, everything works flawlessly. paid $2k for it! I would like to go forced induction there is something about a nice whistle while cruising down the road that I just love. Now for my question, can I install a rear mount turbo and keep it at 7psi on a stock motor/drivetrain that has 100k miles? I don't race to any degree except I love on ramps to the highway. I've read that the l98 stock will hold 8psi without an issue. I know I will need bigger injectors, and a tune. but what about the rest of the drivetrain? Below is a list of recently installed replacement parts on the car.
new Injectors
new egr
new ingition from distributor to plugs.
new exhaust including cats
new timing chain and gears
Actually, if you want to go real economical on this...
MSD 6-BTM ignition box (will allow you to retard timing up to 3-degrees per pound of boost)
Rising rate fuel pressure regular from one of the well known vendors
inline fuel pump to support need for more fuel
now the "right" way:
larger injectors (some will say 42#, but I went to the 60#'s and they are "as easy" to tune with)
in-tank 255lph pump
Tune the computer on a dyno (under load) with a wideband to see what the AFR's are at. As long as you're safe there. You should be fine.
Max boost on a bottom end will come down to intake temperatures, AFR, etc. For instance, we've seen a number of guys here on the forum run more boost with intercoolers and the appropriate tune. Of course, it also comes down to the health of the engine internals and it's all a matter of time before you'll eventually need a better bottom end for the application.
Congrats on the purchase (it makes me sick to hear a good c4 sold for $2000), but of course it's a great deal for you. Post up some pictures!
the older c4's do lend themselves quite well to single rear-mount turbos because the older c4's basically go from the headers to cat's into a single pipe, and than back out to duals. so the merge can make it much easier to retain the stock exhaust from there forward.
contact RAptor Racing (here on the forum) and STS to see what options you've got available.
Psi doesn't break motors first of all. 8psi from a small turbo (t25, td05h, etc) is going to make less power than 8psi from a large turbo (GT42R, BW S372, etc). This is due to compressor efficiency, variations in charge density, stagnation loss difference, etc.
Work more based upon what power the motor can make safely, then base that number on the amount of cfm the turbo makes at a given pressure ration as combined with the mass flow rate of the motor, etc..there are calculators online to make it easier.
The ability to boost a motor is pretty much only based upon the health of the motor. Oil consumption is a big problem, as the presence of oil in the combustion process reduces the octane rating of fuel. This could lead to big problems with detonation and then broken or melted pistons. A compression or leak down check are good ways to get an indication of the health of the motor. If your really concerned about it, check into those methods.
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Single Rear mounted turbo... Stock motor 100k miles?
