The 24 Hours of Lemons Forums → Lemons Newcomers → Mitsubishi, Worst Idea?
So I want to race a DSM engine. This seems like a terrible idea, as the early 90s talon/lancer/eclipse seem to be pretty darn unreliable. My question is twofold: Is this just a waste of time? If its just stupid idea but has a chance of success, any suggestions as to what I can do to make it last longer?
Brilliant idea. No, really. 
Its never a waste of time. Its a) Lemons, b) educational, c) entertaining.
Ok good. On to the more important question of trying to make it semi reliable and/or not as unreliable as if I do nothing. I will do the balance shaft removal, I also seem to remember these cars having horrible electrical problems so lots of zip ties will be employed. Any other suggestions?
I could be wrong, but wouldn't leaving the balance shaft in place make the engine run smoother and thus potentially be more reliable? Removing the balance shaft is a PERFORMANCE mod.
Bring a spare set of head gaskets, and beef up your cooling system.
I could be wrong but as I understand balance shafts, they just spin really fast to counteract the fact that the descending and ascending pistons are not completely opposed to one another. I thought the negative to removal was that the car would shake more, but the positive was basically less moving parts in an engine to lubricate, removal of a belt that if it dies takes the timing belt with it, and I think there are some bearings i don't want thrown into the engine. Then again, my lack of knowledge is why I'm here in the first place, so please correct me!
If you don't know what you're doing or exactly what will happen with the engine if you remove the balance shaft, then it's best just to leave it as is. The possible reward isn't worth the risk, especially when you're doing an endurance race.
So I want to race a DSM engine. This seems like a terrible idea, as the early 90s talon/lancer/eclipse seem to be pretty darn unreliable. My question is twofold: Is this just a waste of time? If its just stupid idea but has a chance of success, any suggestions as to what I can do to make it last longer?
No waste of time at all, just make sure not to overheat the engine and run a bit heavier oil in it. We just finished the PBIR race in a 1991 Eagle Talon TSi and finished the race in 11th. Only thing is these cars tend to push a bit.
Mitsus get a bad rap because they're so cheap, inexperienced mechanics get them and try to break land speed records and it doesn't end well.
A beefy cooling system, a little extra torque on the head bolts, and lots of luck should get you there. The main reason to delete the balance shafts is to remove the belt that drives them. If that belt breaks, it can get into the timing belt, and since it's an interference engine the valves get bent. Look into getting the oil cooler off of a 1990 car too, it's air/oil instead of the janky water/oil cooler the later ones used.
Check out vfaq.com, it has most of the maintenance stuff you'll want on there.
If you want to get really LeMony, the turbo DSM motors will swap into a Hyundai. We actually considered this before we found our Jag. One of our team members has a beater AWD turbo DSM that he abuses for fun, but the Hyundai owner wanted far too much for a seriously funky POS.
Let me fix that for you.
Mitsus get a bad rap because...
...they are worthless piles of pot metal parts designed by war criminals, butchered by accountants, and cast from recycled Stromburg carbs and V-2 rockets.
Let me fix that for you.
CarRacer wrote:Mitsus get a bad rap because...
...they are worthless piles of pot metal parts designed by war criminals, butchered by accountants, and cast from recycled Stromburg carbs and V-2 rockets.
So what's the problem with them then?
The main reason to delete the balance shafts is to remove the belt that drives them. If that belt breaks, it can get into the timing belt, and since it's an interference engine the valves get bent.
You might want to remove the drive belt, but actually leave the balance shaft in place.
If you remove the balance shaft, the oil feeds to the shaft bearings will be wide open and will leak a lot of oil. That might drop your engine oil pressure (like having a huge leak). So leaving the balance shaft in place will keep those oil holes filled up and keep the oil pressure in a normal range. Since it just rotates in place, and doesn't interact with anything else, this should work fine.
The problem seems to be the drive belt, so remove that.
If it's really a belt, you should be able to cut it off, without disturbing the cam belt.
You could just put a new belt on so there is little to no risk of it breaking during the race.
You could just put a new belt on so there is little to no risk of it breaking during the race.
This.
I think the typical DSM failure is more of the main bearing and head gasket variety. If you want to finish the race, put in new bearings, a new oil pump, new head gasket (properly torqued, run-in, and re-torqued) new belts and hoses all around, a good radiator and an oil cooler.
Or... just practice your engine swap technique and bring several spares.
Is that what the track geeks were running last year? you might talk to them they were parked next to us in the garage with a blown motor or head gasket at CMP's fall race
Ive had 3 talon tsi awd's and all of them spit out balance shaft bearings. To remove them you need to take out the balance shafts theres 2 of them, the front is belt driven, the rear is driven off the back of the oil pump. On front, remove the shaft and put in new shaft bearings, but don't line up the oil passages, off set it so the bearing blocks off the oil passages, then plug the whole in the front of the block. On back cut the balance shaft off the back of the oil pump assembly so theres only a stub left, and do the same thing with offseting the bearings.
Do not run with only one balance shaft, they are both there to offset eachother. With only one it will shake worse then having none at all.
Aftermarket places sell kits like these for around $40, but it can be done for much less, under 10 bucks if you can source the parts yourself
http://www.cimotorsports.net/motor-spor … -4g63.html
I actually have a 96 talon tsi awd, with a 6 bolt 4g63, so I have a little experience with the Mitsu engine. I say for sure ditch the balance shafts. If done properly, it should improve the overall reliability of the engine. It's not so much a performance mod as it is a reliability thing. The way I understand it, these shafts spin at twice the engine RPM, so I can imagine, lubrication is pretty crucial to these. All the balance shafts do is to mask a vibration that is inherent to the motor by adding a canceling secondary vibration, if that makes any sense. Just an unnecessary part that can fail. Remove it. These engines need all the help they can get in the reliability department. Also, they can handle quite a bit of boost, but I wouldn't recommend that for an endurance race. If you go turbo, stick with small boost.
Also, speaking from experience, on the turbo motor, there is an oil cooler attached to the block that the oil filter fits onto. When removing that filter, it's easy to loosen the oil cooler from the block. I dropped all of my new engine oil out merging onto I-35 that way once. Quite a spectacle. I'm sure no one is as stupid as me, but just some advice from a dumbass: Make sure the nut holding the oil cooler is tight before replacing the oil filter.
So my semi increased reliability checklist (I'm sure something else will break regardless) thus far is:
Beefy cooling system (Giant jy radiator smashed in)
Balance shafts removed
New Head Gasket torqued, broken in, re-torqued
New Oil Pump
New Bearings
New belts all around
New oil cooler
I think the turbo runs around 11 psi stock. I will turn it down to around 8.
Please add to the list! Also feel free to subtract, I really appreciate all the input.
Oil pump may be more than you want to spend. If you're replacing that, it's a good idea to replace the front case. They wear in together. You're better off just checking the end play of the gears with a feeler gauge and making sure it's within spec.
Do everything you can to protect the alternator from heat. Their placement is right next to the downpipe. The exhaust manifolds are known to crack, the 2nd generation exhaust mani is a good upgrade on the cheap.
Ive had 3 talon tsi awd's and all of them spit out balance shaft bearings. To remove them you need to take out the balance shafts theres 2 of them, the front is belt driven, the rear is driven off the back of the oil pump. On front, remove the shaft and put in new shaft bearings, but don't line up the oil passages, off set it so the bearing blocks off the oil passages, then plug the whole in the front of the block. On back cut the balance shaft off the back of the oil pump assembly so theres only a stub left, and do the same thing with offseting the bearings.
Do not run with only one balance shaft, they are both there to offset eachother. With only one it will shake worse then having none at all.
Aftermarket places sell kits like these for around $40, but it can be done for much less, under 10 bucks if you can source the parts yourself
http://www.cimotorsports.net/motor-spor … -4g63.html
I had the kit that came with bearings sans the oil passages. I have heard that on the cheap, you can flip thestock bearings around so that there is no chance of the oil passages lining up. Havn't actually done that myself, but that's something I would look into if Lemonizing a 4g63.
Also, in case you didn't know, to be safe, stay away from the later "7 bolt" motors, & atick with the earlier "6 bolt" ones. I don't know how much it's been blown out of proportion in the internet, but I wouldn't want to chance the dreaded crank-walk!
I don't know how much it's been blown out of proportion in the internet, but I wouldn't want to chance the dreaded crank-walk!
nah, i don't think the internets have picked up on it
EricTheBrown wrote:I don't know how much it's been blown out of proportion in the internet, but I wouldn't want to chance the dreaded crank-walk!
nah, i don't think the internets have picked up on it
Ha Ha! I had a feeling the internet would never exaggerate! Crank walk is real!
The 24 Hours of Lemons Forums → Lemons Newcomers → Mitsubishi, Worst Idea?