1 2
mthomson22
mthomson22 New Reader
12/16/11 4:47 p.m.

As the title states, I'm looking fairly seriously at a 1988 Mitsubishi Starion Intercooled turbo with auto trans. Stock G54B with recent rebuild.

I know nothing about these cars other than I always lusted after that body.

Please learn me all goods and bads.

many thanks, mark

jhaas
jhaas Reader
12/16/11 5:33 p.m.
mthomson22 wrote: "with auto trans"

PUKE

mthomson22
mthomson22 New Reader
12/16/11 5:38 p.m.

grrrr, i have to use an auto.

look here: http://www.miata.net/motm/2007/thomson.html

JThw8
JThw8 SuperDork
12/16/11 5:47 p.m.

I've owned 3 with manuals and driven the auto, its not terrible with an auto, still quick and fun. So if you have to have an auto (read your link, fully understand) it's not terrible.

The car's themselves however, I love them, but they are the epitome of 80s fuel injection. Vacuum lines everywhere many little things to go wrong. But when they are right, man are they fun.

Like most other things, buy the best one you can afford and you will enjoy it :)

imirk
imirk Reader
12/16/11 5:50 p.m.

Just don't upgrade the turbo and forget to upgrade the cooling system...

turboswede
turboswede SuperDork
12/16/11 7:04 p.m.

They are Japanese Muscle cars essentially.

The lack of rack and pinion steering tends to put them at a little disadvantage when compared to the 300ZX and others of the time.

The common problems are mostly solvable with some effort. Paying attention to the chain/guides, replacing the vacuum lines or just moving to EFI (MegaSquirt, etc.) will help clean up the engine bay.

I think the engine can be swapped to a 4G, so you can have as much power as the crank can walk around with :)

Steering isn't too bad to live with, but with some fab work could be changed to rack and pinion.

I don't know how robust the auto is or if there are any known issues with them or if they are compatible with the 4G motors.

From what I hear, they are still fun to drive and pretty capable cars.

mthomson22
mthomson22 New Reader
12/16/11 7:45 p.m.

Thank you guys. I've been reading everything I can find and have stumbled onto a couple of good forums.

Any more insight from you guys here would still be very much appreciated.

mark

Vigo
Vigo SuperDork
12/16/11 8:41 p.m.

The only thing i will say here is that a lot of the fuel injections system's bad reputation comes from owners not understanding how it works before modifying the car.

For example, later cars switch from a high duty cycle on one injector to a lower duty cycle on two injectors at a certain point, so if you replace the injectors with ones that dont maintain the stock size ratio you will create a problem area in the fueling that will be difficult to tune out and could blow up the motor (the motor is usually in boost at this switchover point).

I honestly think the head has good flow for an old 2v sohc design, but the intake manifold and throttle body themselves are not that great. Still, many people have dynod 300whp through the stock top end. The bottom end is very strong.

11110000
11110000 Reader
12/17/11 6:21 a.m.

I hate to admit it, since I love me a good manual, but automatics and turbos are great dance partners, at least as far as acceleration goes. When the auto shifts, the turbo stays on boost and you get something close to optimal acceleration. Shifting a manual, you get dips in the power when you blow off that boost and have to re-spool.

While I'd have to have some kind of manual 'box in a 'sports car', I could live with an auto in a 'GT' car. The Starion could conceivably go either way.

mthomson22
mthomson22 New Reader
12/17/11 11:12 a.m.

Great info, especially on the injectors. I have read that they can be finicky, tinkering without knowing exactly what's going on sounds like a bad idea with these cars.

I was investigating a Jackson Racing supercharger setup for my auto Miata and heard the same things re staying in boost while the trans handled the shifts.

friedgreencorrado
friedgreencorrado SuperDork
12/17/11 3:34 p.m.

Not much technical help here, but personally I think they're visually so stunning that a little extra effort keeping the FI in shape would be worth it. Factory box flares FTW!

They've got a little racing pedigree as well, IIRC they were the thing to have in SCCA Pro Showroom Stock endurance racing.
http://www.davewolin.com/86champ.htm

mthomson22
mthomson22 New Reader
12/17/11 6:20 p.m.

Beautiful!!!

MadScientistMatt
MadScientistMatt SuperDork
12/18/11 12:30 p.m.

I know a lot of '80s era RWD Mitsubishis used a Chrysler A904 automatic. Not sure if the Starion had one or not, but it's likely. The A904 is a three speed with pretty low losses, and there's a lot of shift kits, etc. for the muscle car versions. Some experts call it one of the greatest drag racing automatics of all time. Not sure how much of the parts cross over to the Mitsu version, but I'll bet a lot of it does.

mthomson22
mthomson22 New Reader
12/19/11 7:37 a.m.

After reading until I could barely concentrate I have found that I want one even worse now!!

Actually Matt, even the Conquests were just rebadged Mitsu Starions and all of the auto trannies were 4N71B's. Not a lot of support out there for those.

I searched cl, ebay, club sites and finally stumbled onto an unmolested jewel. Wish me luck on closing the deal

mark

MadScientistMatt
MadScientistMatt SuperDork
12/19/11 8:39 a.m.

In that case, you could probably put a A904 out of a Mighty Max or RWD Colt in one of them if you need a beefier setup, possibly with A999 internals. The Mitsu case might not be the easiest thing to find - unless Mitsubishi used a Chrysler bolt pattern. Stranger things have happened.

zpeed7
zpeed7 New Reader
12/19/11 9:06 p.m.

I love these cars. My best bud had one and we worked on it for years. Lots of fun and easy to work on. A few tips: Overheating is deadly for the cylinder head, they tend to develop cracks between the valves. Like others have said, don't even think about it and replace the stock efi with an aftermarket one like megasquirt, microtech, or haltech. The stock efi is just a pain. At higher boost the biggest problem is the stock intake manifold, its just a poor design that leaves 2 cylinders overly rich and 2 overly lean, don't ask how I know, a custom canister type intake is going to give some serious hp/torque benefits. The stock turbo is stupid small compared to the size of the engine, If I remember correctly, we used a to3/to4b hybrid and got around 350 whp. The car has very good balance, but the steering felt overboosted, but so was the Rx7 and z31 of that time. Wheel size are weird so custom wheels are the only way to go. We ran into a problem once where the car was misfiring all the time, turns out the timing chain tensioner spring was spent and the timing chain was getting pretty loose and jumping a few teeth on the sprocket causing havoc with the timing.

Back in the day Buschur racing had an auto running into the 9's

but I don't remember if it had the eclipse/talon engine. They also made a complete conversion kit with engine mounts and everything to get the eclipse/talon engine in there.

Let me know if have any questions and good luck.
mthomson22
mthomson22 New Reader
12/20/11 6:52 a.m.

zpeed7, I've read about the potential for overheating and will likely swap out the radiator for an aluminum 3 core in the near future.

When you say 'a custom canister type intake is going to give some serious hp/torque benefits' do you mean just the filter assembly or the whole intake manifold?

I'm wanting to stay relatively stock, with bolt on intake/exhaust mods...for now.

+1 on the odd wheel size. The model I'm grabbing is an SHP, which has 16x8 front wheels using a 225 50 16 tire and 16x9 rears calling for a 245 45 16 tire - which I'm finding is an oddball size currently. I've read that 245 50 16's mount up fine with no clearance issues tho.

thanks again, mark

MadScientistMatt
MadScientistMatt SuperDork
12/20/11 7:29 a.m.

One of the hot ticket parts I've seen is using a Mitsubishi Magna intake from Japan or Australia to upgrade from the stock throttle body injection to a multiport setup. Not sure why Mitsubishi used throttle body injection with a turbo; they're the only company I'm aware of to have sold that combination in the US.

mthomson22
mthomson22 New Reader
12/20/11 9:22 a.m.

Matt, that would require stand alone engine engine management, correct?

zpeed7
zpeed7 New Reader
12/20/11 11:01 a.m.

In reply to mthomson22:

MadScientistMatt wrote: One of the hot ticket parts I've seen is using a Mitsubishi Magna intake from Japan or Australia to upgrade from the stock throttle body injection to a multiport setup. Not sure why Mitsubishi used throttle body injection with a turbo; they're the only company I'm aware of to have sold that combination in the US.

Yeah, this exactly why the stock efi is just a pain, there's just no way to distribute the fuel mixture evenly. That's why a new intake manifold and after market efi with one injector per cylinder is the way to go. The stock system is fine for the stock turbo. If you leave stock they do respond well to exhaust upgrades but the stock turbos don't last much at higher boost pressures.

There's a lot of potential in that engine. At one point in time, a Starion/Conquest engined car was the fastest 4 cylinder in the world:

http://www.the-oilman.com/race/sakura.html

sakuramotorsports.com/

mthomson22
mthomson22 New Reader
12/20/11 12:43 p.m.

I do plan on leaving the stock turbo, and am looking to mildly enhance the breathing with a less restrictive intake filtration unit, and open up the exhaust side, including the downpipe.

I read on 1 vendor's site that opening up the exhaust side would result in, obviously, quicker spooling and, surprising to me, 2-3 lbs additional boost pressure.

With that being said, I'm wondering if you guys could recommend a vendor or manufacturer as I've read conflicting info on some products and vendors.

mthomson22
mthomson22 New Reader
12/20/11 2:36 p.m.

These guys seem to have a handle on StarQuests http://www.racetep.com/dod_mit.html

Any personal experiences with them or their products?

zpeed7
zpeed7 New Reader
12/20/11 6:01 p.m.

Well, they have been at it since back in the early 90's, and apparently they haven't changed their website since then either hehe. Never dealt with them though. That picture did remind me of a few things though. One of the most inexpensive improvements you can do is to replace the stock rubber intercooler piping with metal tubing. It will improve throttle response and hold boost better. They tend to get toasted with time and leak, even when they look ok. Also when you add the exhaust and get a few more psi you should add a blow off valve, IIRC the car did not come with one from the factory and at higher boost, the back pressure when the throttle closes makes the turbo stop and spin the other way killing the shaft pretty quickly. As far as exhausts, we bought U tubing from Summit and had a muffler shop fabricate a full 3' exhaust with a round Borla xr1 at the back. Worked great but is was pretty loud. Later we added another shorty regular xr1 in the middle which toned it done quite a bit.

mthomson22
mthomson22 New Reader
12/21/11 7:09 a.m.

zpeed, I read that 3" would be overkill for a stock turbo configuration, and would actually hurt off boost performance, the recommendation was for 2.5 inch dp and full exhaust with a flow-thru muffler. Were you running the stock turbo?

You are spot on with what I've read about adding a bov, and that'll be one of the very first mods.

thanks for the advice, mark

failboat
failboat HalfDork
12/21/11 7:15 a.m.

what i am reading implies a recent purchase. and you know what that means....

1 2

You'll need to log in to post.

Our Preferred Partners
Xy37F9GMAvZoUOvu4a0LjWaIEb4983MIrvSqvjpgMJKLzL3V187H1nAdUmGqo5TJ