hey i need you guyses help on this one. now i know this isnt about 3rd gens but i need to know. my pops wants to put a turbo on his 79 spitfire. now heres the question cause most of this is gonna be custom fab. when we go to hook it up does all of the cars exaughst run through the turbo, or only part of it? if only part of it does would have to rout the out put of the exaughst from the turbo behind the cat and mufflers. ive never seen a turbo setup before, so i dont really know. are there any oil lines that have to go to the turbo? that wont be a problem because its going to have a cooler. thanks for the help guys.



-Bruce

oh and hes go either 9.5 or 10:1 pistons to go in there i should probably stick with something low like 5 psi right?

 

if I read your post right then all the exhuast from the car should go through the turbo. though the exception comes with a wastegate, if your car is only to put out lets say 6 psi but due to the mods you have the car might be wantingto push out more so you put a wastegate in there and it will allow some of the exhaut gas to bypass the turbo so your boost doesn't go past the 6 psi

and yes every turbo I know of has an oil line that goes to it
and a lot of them even have a coolant line to help with the cooling of the turbo a bit

I would look up how turbos work quite a bit before you attempt thistough cause with a turbo motor. they are worth the gains but just more work and tuning is needed

 

thanks man, one more question about it though. about the wastegate, the waste gate is like a pressue regulator befor the carboraters right? itll just releve presure when it goes above a specfied amount correct?


-Bruce

thanks for your help man you cleared up a lot of confution

 

it is on the exhaust side
some turbos have a built in wastegate
others you have to buy an external one.
they sit in paralell with the turbo though so when boost gets high enough the exhuast bypass the turbo so boots does not get too high

 

check out my "PICS" thread. The turbo I have has an internal wastegate.

 

Ok this is something I have been explaining to guys at school in my spare time.


Waste gate. Modulates the INTERNAL Exhaust pressure on the exhaust side obviously. It allows Exhaust to bypass the turbine and flow through the tubing to the down pipe.

ALL CARS NEED THIS. ALL CARS ALSO NEED A BLOW OFF VALVE.

A blow off valve is another thing to help regulate the pressure going to the throttle body. EITHER CARB OR MPFI. The blow off valve keeps the pressure in the intake tube at the same PSI level you have set the turbo for. IE MANUALS, when you go and downshift the pressure in the intake tube can increase by 4 PSI by the throttle plate closing a little, now imaigine if it goes almost completely closed? wheres all the pressure gonna go? back into the turbo and shread bearings. The blow off valve DOES HAVE ITS OWN SETTINGS. You can set it for a different pressure then your turbo OUTPUT PSI, It just helps "dump" the PSI on downshifts to keep it from backwashing into the turbo.

COMP ratio. The more Boost you wanna run the lower you go. IE normal non turbo you run say 9.7-1(I know the MGB's run that) And you want to run 6 PSI, Lower the ratio to around 8.5 and you SHOULD be good to go assuming you have built the motor to take that. If you want to run higher PSI LOWER THE RATIO, Or you WILL blow bearings along with other vital parts.


OILING. YOU ALWAYS WANT COOL FORCE FEED OIL. The best way is the oil pressure sending unit. Put a "T" there and run it into a oil cooler, then to the turbo. GET A TURBO TIMER. Around 80-100 bucks and IT WILL SAVE YOUR TURBO. WHEN you have a turbo equipped car you want the motor to run for 3-7 minutes AFTER YOU "want to get out" to help coll the interal surfaces of the turbo. This prevents you from cooking the bearings and hense burning out the turbo.

 

thanks camaro hunter. everything is clear now