Having spotted what the compression for the new Lancer is for the LandDown under I am wondering if you guys have changed the compression on your cars yet we are looking at only having a compression rate of 9.5:1 and was looking at changing it to something a little more like 10.5:1 anyone here got any thoughts here or have done it,, would be very interested in your results

 

Ive been wanting high compression pistons for awhile. 10.5:1 or 11.0:1 can get you about 20-30whp. I know the 4G Eclipse GT has 10.5 compression and I heard when MIVEC kicks in, it's nastier than ours.

There was a thread that a shop somewhere back east (USA) was going to make some for the ralliart, but I don't think anybody follow up with the the shop. Ill try to find it.

 

I would buy those in a heartbeat, so get a GB happening, after you find some of course

 

Here is the thread: https://www.evolutionm.net/forums/sh...d.php?t=151264

Has anybody call? If not, I can give them a buzz monday morning... but there probably gonna need a ralliart in the NJ area.

 

There was a thread awhile back concerning an older Mitsu 2.4L engine (2G eclipse?) that had the same pistons and rods as us, thus meaning that aftermarket pistons/rods for that engine will work with the 4G69.

 

Note that the pistons might not be so expensive but the install will be.
My set costed me $700.00 and then $700.00 in parts and labor. Some people have gotten quotes for about $1000.00 just the labor.

I'm only posting this to let you guys know it's not going to be a regular bolt-on. Higher octance gas, colder plugs, thicker oil, lean spots, preignition, etc.
Don't ask for something you don't want to deal with.

And for those that really want pistons just call CP or Ross's Pistons or JE and ask them to make you guys a custom set. I'm sure they will do it.

 

^^^after reading that im starting to save up!

gregivq how did your set work for you, worth the money? Either way i'd be willing to save up and sacrafice a few months of staying home on the weekends to save some cash. Just wondering what your expierence was with this.

 

Well, like I said it involves a lot of work and I probably wouldn't have done it if not Boeturbolancer who was always helpful.

The pistons are awesome. Probably the best N/A mod. With a Mivec engine it should work even better since these suckers love air. I don't even want to mention the last race on a highway with one of the lancers. Dude looked a little confused.

 

If you for a challange go for it. But watch out, I still have a problem with a terrible "diesel" noise coming from my valvetrain. Reason? Nobody knows. It might not be related to pistons but it's still there annoying the $hit out of me.

 

Is there a risk you run by going up to 10.5:1? Would you have to alter anything else?

 

depends. its not a big jump but changing compression ratio just a bit can make a big dif in the combustion characteristics. i think the biggest worry will be the spark plugs, which can be replaced on the cheap side. the ecu should handle the rest

 

yes i would like to upgrade compression since thats only thing left to do.... for me anyways, goin na. turbo is just way to out of my leuge.

what all involes doin pistions??? take out the motor or can you just do it in the car>???

 

With the 02-03 Lancer the install can be done in about 8hours or less. For people like Boeturbolancer it takes about 4hrs.

With the pistons I bought some 20W-50W oil for the break-in period $10, new head gasket $40, timing belt $30, head bolts <$100, new plugs, and I think that was it.
If you are not going to buy new rods you will have to have the person installing the pistons go to a machine shop and have them press down the rods with the new pistons $50.00

After all of that you would have to make sure your spark plugs look ok.
I bought a fuel pressure regulator to make sure my AF ratio is not lean. And then just a brake in period and after that oil change and let's go.

Now my next step will be tuning cuz I know it will free up lots of ponies!


You don't have to take out the motor to swap pistons altough some shops will insist to do it for better access and blah blah blah.

 

One step colder plugs and 93 octane gas. Also your A/F ratio (if you are going to tune it) needs to be a bit richer than regular NA.

 

Pistons can be done in-car. I'm pretty sure that you can do it just by removing the head (not easy) and the oil pan. Insert piston/rod combo from the top using appropriate tools, then secure it to the crankshaft from the bottom.