few questions about my turbo

[Diablo]

i have a 91 daytona shelby and i recently had a leak in the oil feed line. i took off the line and am waiting for a braided one from fwdPerformance. i dont know much about turbos being this is my first turbo car. the turbo spins very nice and dosnt seem to have any side to side movement so im assuming it is fine. however ever since i got the car it hasnt broke the 5psi mark. is there some sort of ajustment on the wastegate or somthing there that would wear out and not allow the turbo to reach 7psi? i went through all vac lines and replaced them so i don't think there is an issue there. im pretty sure its a mitsu turbo but again i don't know how to tell.

thanks

[moparfreak3]

Well as far as identification here is a reference picture. This is a comparison between a t2 garrett and a t1 mitsubishi. As far as the boost you may have a bad wastegate actuator. You could try butting washers between the wastegate acutator mount and the turbo but chances are you would be better off replacing the actuator.

[Diablo]

thanks for the info and the pictures. even with the turbo still crammed in the car its definitely the mitsubishi. from what i have been reading on here its worth the swap to a garrett. but again im new to turbos and don't know what would go best on my car. its bone stock right now but i plan to do some work to it. but i still want to keep it as a daily driver. a budy of mine works on turbo cars, not dodges, suggests a t3/t4 hybrid. would somthing like that be my ticket or is there another combination that works well?

[moparfreak3]

A garrett will work well for a dd you wont have to change anything except the turbo and lines. With a hybrid you will have to either change the manifold or modify yours to work with the standard t3 flange, also the oil and coolant lines, the exhaust, and charge pipes. There are a few people on here that use hybrids on their cars with great success. In my opinion if you are like me with a limited budget I just had my garrett rebuilt and modified with a bigger compressor wheel. By doing that I won't have to change everything like with a hybrid.

[Diablo]

thanks for the advice. hopefully i can get a garrett in the near future but for now i have to settle for the mitsu. i was looking around the forum today and found a test for the wastegate actuator and it was if it moves under presure and holds vacuum it should work and mine passed both of those. however if i understand how it works theres a spring in there that controls how high it will let the turbo boost until it opens the gate. when i bought the car it didnt have its vacuum lines hooked to the wastegate at all i think it just had a screw in it. would this push the wastegate open if boost got too high and some how damage the spring in the actuator?

[moparfreak3]

Is the screw in the vacuum nipple or in the body of the actuator?

[EvilcowRoland]

If your wastegate can isn't hooked up to vacuum at all, it should be allowing it to reach maximum boost. The way it works is the boost pressure pushes on a diaphram in the can and moves that arm which opens the wastegate so the turbo can't continue to build up pressure. If that can never sees boost, it'll keep spooling until the internal pressure forces the wastegate open (like, 18-20 PSI on the Mitsu). Obviously that much boost is bad for a T1 car. If you're only getting 5 PSI then either the spring in the can is dead, or more likely you have a vacuum leak somewhere. I say more likely because obviously the vacuum system has been messed with before you got it. Go through and make sure all of your vacuum lines are present and intact.

As far as turbos go, what you want to do with the car determines what turbo you should use. I wouldn't go hybrid unless I wanted to make big power. If you just want a peppy daily drive, stick with the Mitsu and add an intercooler with boost set to 12-14 PSI. Minimal modification involved and you're at the limits of the stock fuel and MAP system anyway. A Garrett will make more power in the long run and the air charge won't be quite as hot as the Mitsu, so it can make more power pound for pound of boost, but for a daily drive I like the quick spool up of the Mitsu. Your results may vary. The Garrett can make a good DD as well, but it means you have to locate one and then swap it. Why spend the money if you don't need to? Now, if you're more concerned with performance then I'd definately recommend the Garrett. I have a 2.5 with Mitsu and a 2.2 with the Garrett. The Garrett equipped engine is definately more fun, but the Mitsu equipped one seems to have better street manners. Size of the engine matters there too I know, but the turbo response is what I'm referring to mostly.

[Diablo]

they're were a couple of them but i redid all of the vacuum lines to match the sticker under the hood. when i drove it home i was making about 3 lbs and now its at five since all of the vacuum issues were delt with

[Diablo]

ok now i got the oil line back on the car and hooked up all the hoses and made sure they were tight. now im up to 6 psi! but i was wondering how high i could go with the stock fuel regulator and stock computer. and if it can go to 8-10 what would be the best/cheapest way to do so?

thanks

[Ghostof309]

I put a manual boost control (g-valve) on mine. I have an 89 Lebaron with a 2.5 and a mitsu turbo. It's cheap, about $25 from FWD Performance and simple to hook up. You hook one end to the vaccuum hose going to the nipple on the turbo housing and one end to the vaccuum line going to the nipple on the wastegate. To adjust the boost you simply loosen the lock nut and turn the fitting out to lower boost or in to raise boost. Start with the fitting adjusted out first and work your way up slowly until you reach the boost level desired. I wouldn't go past 11 lbs of boost though without an intercooler. I added an intercooler to mine and am still running only 10 lbs of boost and for a daily driver its got plenty of kick for me. Believe me, I'm no expert on turbo cars and I am by no means a mechanic so when I say its an easy hook up, I mean it.

[EvilcowRoland]

Yeah, you can use a manual controller and crank it to 10-11 PSI safely without an intercooler. (stock boost levels on some later T1s). With an intercooler, the stock fuel and computer systems can handle up to 14 PSI without much worry. Manual boost controllers are dirt cheap. I bought the parts and made one for around $10. The vendors sell them premade for I think $25.

[Diablo]

Awsome...thanks for the help!!