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Been reading over this post and really seams there is alot of knowledge here. Not trying to jack your thread, but quick question. Ill be building an engine over the winter ( my first ) well not building but having built. Im looking for a bottom end that will handle 30psi and be able to handle much much more. Id like it to handle mid - hight 20 psi on pump, without meth.
My question is what rods and pistons do i want? Or what would be a good starting point as to start reseaching.

Thanks.
 
Im putting mine togther right now with wiescos and eagles with a cometic mls. I think Ive decided on .0035 piston to wall clearance. Ive been trying to get in touch with Wiesco to find out the ring gap numbers but everytime i call Im on hold for too long and have to hang up.
 
I used crower rods and wiseco pistons in my 2.4 .Eagle rods are cheaper and have taken big power also but I got a screaming deal on the crower rods used so got them instead.
I ran my wisecos at .0035 and am using normal street break in.The wiseco are measured different in a different place from most other pistons and coated so the coating after it wears off would make them like .0040 or something and the piston to wall is not directly comparable to other pistons that measure different.For example Ross recommends .005 and think going up .001 or so for big boost. My wiseco specs were .0025 in the box but I am hitting it with 30psi very occasionally and maybe under 100 shots of spray also very occasionally.
I talked to lots of guys that ran from .003 to .0035 to .004 on the wisecos with no problems..
Course nuke ran wiseco at .004 and his engine died an early death but that doesn't seem to be the norm. Guys are running with .003 and .0035 just fine.
For ring gaps again think might depend on what piston you use.My wisecos are set at .019 top or .020 and about .023 second think even .021 is fine.
Most gap the wisecos bigger for sure on top.Guys have run big power thru them at .019 and .021.
I can't give you a report of how things are working out for me as engine is still being final assembled and being dropped into my car in next week or two.
Also I used arp head studs and cometic hp gasket and sprayed the cometic with copper spray even though they said to put them in dry they also said not going to hurt to use a bit of copper either. My head and block were smooth and decked minimum amount.I didn't use arp mains I used stock main bolts. I didn't want to align hone and did buy a CRCO dowel kit but it is a pain to do on the 6 bolts.Guys have also made big power on stock main bolts.Not too worried. If you are a 2.0 I would use the mits mls gasket they are proven to work well.
 
Wow. This thread is mind boggling. Something was certainly wrong with that engine. I'm leaning towards either a measureing defect or some type of manufactures defective part.

I'm running wiseco's on factory 1g rods. i don't remember exactly what my specs were on ring gap and wall clearance but i'll have to dig them up. I do remember going right off of the red wiseco spec sheet that came with the pistons. I've got several 124 mph passes on them and all seems good....knock on wood.

FWIW, you are not the only one who has grenaded a 2.4l motor. As far as im concerned, the rod ratio is not right and the ONLY way to make BIG BIG power is to go 2.0 liter.... just my .02.

keep your head up victor! It will be better this time around im sure.
 
I have talked to lots of guys with like .0030 and .0035 and .0040 and they all ran big boost and some even spray with the wisecos no problem.Most set the ring gaps at .019 and .023 or so for top and second ring.
so pretty sure it was measuring error or something else that wiped the motor out.
You dont' need to run way past .0040 with wisecos. Ross you run like .006 but they are measured different.

And I know lots of guys running 2.4 now not just on this board that are having no problems at all.
The engines are 2.4 already.You are using a 2.4 crank and rods are same so not sure where this weird ratio stuff comes in. Magnus and many others have used 2.4 no problem. Now 2.3 might be a bit weird but lots of guys running those.
I think some 2.4 problems can be traced to screwed or turned cranks,and many more to assembly problems. But guess find out with mine although mine is not a track motor just a street engine. And I have a spare 2.0 6 bolt here also if need it but hope I don't.The 2.0 motor is a joke off boost.The 2.4 I hear is much better off boost and the quicker spooling on bigger turbos is nice also.
Of course my other car is going to be twin turbo v8 7 litre so of course any 4 banger off boost will seem a bit weak compared to that.

There are a lot of 2.4 running around and running well. 2.3 also. This rod ratio stuff is not very believable. Of course I plan on keeping my redline to 7500 ,8000 tops. Some guys might be trying to push these 2.4s to 9000 and stuff..
 
I am going 2.0. Why do you say not to use main studs. Whats hard about useing them. I got my latest order from slowboy today and included with everything i bought i was supposed to get main studs, but they sent me head studs instead. So my motor is still on hold for the machine shop. Another delay.
 
jimib said:
Diambo.. Sorry for the off topic but I could not pm you. I saw you maybee have a set of arp head studs that you would sell. Do you still have them?
YES.

d i a m b o 4 l i f e at y a h o o dot c o m
 
Got to take the car out a few more times and got some more input on the .006" clearence. There is in fact a bit of slap while the car is warming up, nothing Im worried about though. I just dont rev it too much while its cold so I think it should be alright. Once its fully warmed its silent. Like I said before I wont be driving the car on the street so Im confident that it will be fine. Blowby is nonexistent from what I can tell. Ill run another compression test some time to see where Im at there.
 
Discussion starter · #133 · (Edited)
We finally came to a conclusion on this issue the other night. I realized so late after the fact that I was using the wrong spark plugs in my motor. At the time, I was having a hard time finding NGK BPR7ES or 8ES plugs in stock locally, so I threw some 6's in there for the time being since I had them on hand. This was before fitting the meth on the car. Later when I put the meth on, it didn't occur to me how imperative it was that I change the plugs. I simply forgot about it. I should have been running a colder plug to begin with, plus the meth also requires something colder still, so I really needed to be using 8's, 9's, or 10's in the motor. The 6's likely got so hot with all the heat and pressure that they turned from spark plugs into glowing red sources of pre-ignition, igniting the mixture at its earliest convenience. The shock of preignition likely caused the piston to crack in half, and the rest is history.

:chair::chair::chair::chair::chair::chair::chair:

It's all very shocking that I would have been so stupid and not used the right parts. $10 worth of plugs and some patience would have saved me thousands of dollars worth of motor damage. I'll spend a while kicking myself over that, and I'm sure my public credibility will go down ;), but it's already been long enough that I'm ready to move on. I already have some new internals and will be getting the new motor prepped at the machine shop this weekend. This time it won't take me as long to get the car up and running again. Hopefully a month or so.

As for the wall clearance, it would now appear that the motor would have lasted at .004" had I just used the right plugs. For how long, I dunno. There's still the abnormal piston wear and wall scuffing that may not have been a direct effect of the plugs. If I had it to do over again, I still would have gone looser. I am going much looser with the new motor. Get ready for Diary of a Rebuild II!
 
I did tons of research after your engine failure and polled everyone and anyone on the piston wall subject for my wisecos. I found many high power guys runnning 30psi with spray and using .0030, .0035,0040. Talking wiseco proper measurements here not ross which do run more like 0050 or .0060.and measure in different place.
And the key also was bigger ring gaps...019 top or so...021 or .023 bottom.
That is what my engine is set up like.0035 piston to wall,.019 top,.023 bottom.
Also running straight meth yeah you would maybe need to go stupid on piston to wall engines are not made to run straight meth at stock specs. Simple water/meth with the old winshield blue stuff should work fine and let you run higher boost and snow has some nitromethane or something it says on their site that is supposed to work good you add in small amounts for extra 30 to 50 hp it says.
I could see hot plugs definitely causing some big problems.But its hard in hindsite to know what did happen 100%. For sure your piston to wall if correct would not have hurt anything in normal circumstances.I guess the proof will be to see how long my 2.4 lasts the way its set up. But I will never run straight meth in it.And it is getting street break in but not totally babied..Will be taking it from 30 to 70mph or so repeatedly but not at full boost. Min boost is 15psi on my gate right now.
Engine should be running this week mabye next couple days..heck maybe today.

Good luck and liked your photos and your whole project nuke.
 
we had a couple motors from a "rep" shop that developed abnormal piston wall scuffing in the first 500 miles....had a machine shop check it and it wasn't pretty.

also al92 i ended up going with .020 and .024 on my ring gaps with the stock wiseco piston clearance. my pistons are also swaintech coated

nuke if the piston slap gets too bad have a machine shop crosshatch the piston skirt ;)
 
I have a fresh 2.4, can someone tell why he ported his oil pressure relief hole? Do these motor setups run high oil pressure? My car seems to do this now that I have this new setup. I would love to know, maybe I will do that to my car.
 
When you remove your balance shafts your oil pressure normally goes thru the roof. This is not a great thing in most peoples eyes. I ported mine but so far have not started and driven my car. Some guys say to not port ,some say to. Some say have had more leaks and stuff from the higher pressure,some they haven't.It don't seem too clear cut.
But as said I did port mine some and hopefully will work out ok. You can do it after the install of course by just getting that one annoying bolt under the timing cover out.
I am also not 100% sure if not running squirters which I didn't in my 2.4 will have much effect on the oil pressures like 2.0 with oil squirters.
 
Discussion starter · #139 ·
jc8889 said:
I have a fresh 2.4, can someone tell why he ported his oil pressure relief hole? Do these motor setups run high oil pressure? My car seems to do this now that I have this new setup. I would love to know, maybe I will do that to my car.
It is explained elsewhere in this thread.
 
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