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Building a 2.1L need some info...

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jjgrizz73

15+ Year Contributor
816
1
Feb 17, 2007
Carbondale, Pennsylvania
Hey everyone, so Im going to go with a 2.1L destroker because I already have the 2.4L block from my 97 spyder that I swapped a 4g63 into. Im picking up custom pistons to use the standard length rods to make the build a budget build. Im also getting it machined obviously to use a DOHC 2g turbo head. Some questions I have is on the timing components (timing belt in particular) and the exchangability of it from the 2.0 to the 2.4 setup, also the headgasket which Im assuming Cometic or MLS has one available for it. Also am I looking at any type or oil problems (will 1g external oil cooler still work, is oil pump still good, etc) Any other complications I should be looking into before digging in? Thanks!
 
Let me get this straight, you're going to run a 88mm stroke crank and standard length 150mm rods in a 2.4L block that has a deck height of 235mm?

You'll be a full 6mm short of filling the cylinders.

Enlighten me on your rotating assembly design.
 
the pistons have been made with the pin 6mm lower to allow for standard length rods instead of the 156mm rods.
 
That's one way of doing it.
Is it the best way, probably not.
You just moved the wrist pin away from the piston's center of gravity.
You want all of the forces the rod is going to exert on the piston and vice versa to go thru the piston's cg.

This piston may rock in the bores more and actually have some piston slap due to the rocking.
Please report back and prove me wrong once this beast is running...

So, why didn't you go with 156mm rods?
You can get a set of Manley Turbo Tuff I-Beams from SBR for $700 if you contact the right person.
Or, you can get a set of Custom Length Crower Billet Rods for $800.

Personllay I'd rather use an off the shelf piston rather than a custom piston.
If something happens you can simply order up another piston provided the bores are still ok.

What rods are you running?
 
Well I figured Id try these, I get what you're saying though. Ill trust that these JE's will do the job. I havent purchased the rods yet but I have plenty of options with the standard length. Anyone have any answers to the timing question? Also what head studs can be used?
 
Hey everyone, so Im going to go with a 2.1L destroker because I already have the 2.4L block from my 97 spyder that I swapped a 4g63 into. Im picking up custom pistons to use the standard length rods to make the build a budget build. Im also getting it machined obviously to use a DOHC 2g turbo head. Some questions I have is on the timing components (timing belt in particular) and the exchangability of it from the 2.0 to the 2.4 setup, also the headgasket which Im assuming Cometic or MLS has one available for it. Also am I looking at any type or oil problems (will 1g external oil cooler still work, is oil pump still good, etc) Any other complications I should be looking into before digging in? Thanks!

I'm assuming you're running a 7-bolt 4G63 crank in this 4G64 correct?
If so, some 7-bolt Eagle Rods should be sufficient if you don't plan on revving this motor to the moon.
Typically 2.1L can rev to over 11k rpm when built properly.
But, you didn't build this 2.1L like a typical high end 2.1L so I wouldn't rev it high at all.

As far as your timing component questions, there are more than enough threads covering that already. http://www.dsmtuners.com/forums/search.php?searchid=7372368

You can in fact use a 4G63 timing belt on a 2.4L block, you just have to modify the tensioner arm. Search that link I posted above.
Only machining needed to install a DOHC head onto a 4G64 is having the correct oil drain holes in the block blocked off.
The DOHC head does not have these extra oil drain holes.
Again, you just have to search for your head gasket, or may start another thread concerning which head gasket to run on a 4G64 using a 4G63 head.
Cometic makes gaskets for 4G64's.
Not sure you can get a Mitsu MLS for a 4G64, but I have been known to be wrong, from time to time.
The 1g external oil cooler will work, but if you are referring to the 1g Oil Filter Bracket, then that will not bolt up to your 7-bolt front case/oil pump.
You'll need an Oil Filter Bracket off of an Evo III to use on your 7-bolt block, or run one of those sandwich adapter things.
 
Perfect, I have an EvoIII motor in it now so the OFH will be fine then. Good to hear about the timing, I read that thread also, but wanted to make sure. Im not lookign to revv it up to the moon, really 8-8.5k would be fine to me. Its only a DD setup with a 50trim and some meth...getting a trans now too since I blew the front diff out of mine so I figured I'd change some other stuff too :) Thanks for the info Strm
 
You bet, and keep us posted on how that 2.1L works out for you.

I'm going to build a Long Rod 2.0L using an OEM Evo Crank, 156mm custom length rods and 2.3L stroker pistons in my spare 98 7-bolt block.

Should make for an interesting set-up with a Bolt-On HX35 with 70/30 meth injection, I so can't wait...
 
Should be a very nice setup when you're done. I plan on going to an HX40 down the road but for right now I should be ok. So checklist for verification:
4g64 block(have)
4g63 crank
Custom pistons(JE) (have)
Standard length rods(didnt choose yet)
2g 4g63 head (have)
EvoIII OFH (have)
4g63 timing belt/components with some modification to tensioner
Cometic 4g64 head gasket
Standard ARP 7 bolt head studs
 
If you use stock length rods for the 4G63 and the stock 88mm stroke you will have the stock rod ratio. The only difference you could be making is the pin moved down making the piston less stable.

That configuration will have all of the timing problems you are fighting but none of the ability to rev higher. No more than stock displacement. No more than stock torque.

Tell us again why you are doing this configuration?
 
Should be a very nice setup when you're done. I plan on going to an HX40 down the road but for right now I should be ok. So checklist for verification:
4g64 block(have)
4g63 crank
Custom pistons(JE) (have)
Standard length rods(didnt choose yet)
2g 4g63 head (have)
EvoIII OFH (have)
4g63 timing belt/components with some modification to tensioner arm
Cometic 4g64 head gasket
Standard ARP 7 bolt head studs

That all looks pretty good.
Are you running a 7-bolt 4G63 crank?
These JE Pistons, I'd assume, 22mm wrist pin bore diameter?
 
If you use stock length rods for the 4G63 and the stock 88mm stroke you will have the stock rod ratio. The only difference you could be making is the pin moved down making the piston less stable.

That configuration will have all of the timing problems you are fighting but none of the ability to rev higher. No more than stock displacement. No more than stock torque.

Tell us again why you are doing this configuration?

Not sure why he's doing this.
And yes he has mentioned that the wrist pin got moved down 6mm which will definitely make the piston less stable.

I on the other hand have decided to run a Long Rod 2.0L by moving the wrist pin up 6mm and using 156mm rods, and 2.3L pistons.
Should go together well with a 2g intake manifold, 1g TB and a 2g head.
 
Yes, 7 bolt crank -
22mm pin on the pistons , 87mm bore

Im doing it because I have the block and a buddy has a crank...so Im just making a project out of it. The timing issues do not worry me at all and I dont think the piston instability will be that big of a problem since its been done before.
 
Good answer. Sounds like a fun project that should keep you out of trouble for a while.
Enjoy.
 
Thanks for the concern (not being sarcastic) I appreciate the feedback. Has anyone has experience with or knows anything of the custom pistons like this failing or suffering piston slap? Either way Im still increasing the bore and stroke of the motor so some gains are guarenteed, how much I do not know...really all Im looking for is a built motor that can handle a good amount of power without snapping a rod ;)
 
You are only increasing the bore.
You are not increasing the stroke, and you've actually decreased the engine's displacement.

Typically people who destroke 4G64's are using pistons with the wrist pin moved up 6mm, throw in a 88mm stroke crankshaft and use 162mm long rods.

Not using a 88mm crank, 150mm rods and pistons with their wrist pins moved down 6mm.

Are you sure people have done this before?

I don't think you're going to like this motor one bit...
 
I have reduced the displacement of the 2.4L yes thats true but the stroke should still be longer considering the change in deck height correct? I am comparing this motor to a 2.0L not a 2.4L I wont see gains from the longer rods typically used but I'm fine with that since its a budget build anyways.

Mostly I just want an engine I can run a higher amount of boost without worrying about it popping...not looking for a 10k+ rpm motor
 
No, the change in deck height doesn't mean anything.
You didn't utilize it in any way.
You added weight to your piston by moving the wrist pin down and made the piston taller.

The stroke was changed from 100mm to 88mm, thus the displacement was altered.
You changed the rotating assembly total height by moving the wrist pin down 6mm to make up the 6mm gap you had above your piston.

Check it out, here are the differences in a 4G64 and a 4G63:

4G63
4G63 deck height = 229mm
Rod Length = 150mm
Stroke = 88mm
Compression Height = 35mm
Bore = 85mm
Displacement = pi * (bore in cm/2)^2 * (stroke in cm) * (# of cylinders)
pi * (8.5cm/2)^2 * (8.8cm) * (4) = 1997cc or 1.997L
Total Rotating Assembly Height =
(1/2 of the stroke) + (rod length) + (compression height of pistons)
44mm + 150mm + 35mm = 229mm

4G64
4G64 deck height = 235mm (6mm taller)
Rod Length = 150mm
Stroke = 100mm (12mm longer, but only 6mm longer when figuring total rotating assembly height)
Compression Height = 35mm
Bore = 86.5mm (1.5mm larger in diameter)
Displacement = pi * (8.65cm/2)^2 * (10cm) * (4) = 2350cc or 2.350L
Total Rotating Assembly Height = 50mm + 150mm + 35mm = 235mm

So those are the physical differences between both motors.

You did this:

4G64
4G64 deck height = 235mm (6mm taller)
Rod Length = 150mm
Stroke = 88mm (12mm shorter, but only 6mm shorter when figuring total rotating assembly height)
Compression Height = 41mm
Bore = 87mm (2mm larger in diameter)
Displacement = pi * (8.7cm/2)^2 * (8.8cm) * (4) = 2093cc or 2.093L
Total Rotating Assembly Height = 44mm + 150mm + 41mm = 235mm

If you put piston #1 at TDC and measure it, it will be flush with the deck of the block.
If you turn the crank 180* to BDC and measure from the deck of the block to the top of the piston, it'll be... are you ready for this, 88mm.
The stroke is still 88mm, your piston is just taller.
 
Ok thank you, very good explaination. Still though for the price I am building this motor at (which is less than I can build a 2.0) its still going to be no worse than any built 2.0 other than the thought of the piston being "unstable" correct?
 
Well technically you can't achieve that amount of bore with the 63 not that its that big of a deal. But like i said I can build this block for less than a 63 block so why not?
 
Sure is a waste of a good 4G64 though.

100mm Stroke
156mm Rods
+6mm wrist pin Pistons

That my friend equals the baddest of big blocks, the Long Rod 2.4L.
More power and torque than the standard 2.4L and still rev higher than the standard 2.4L and the stroked 2.3L, and do so safer.
 
Wasnt really looking at torque as the reason for building this motor, same goes for revving as I stated. Being FWD (for who knos how long) would only be a waste of that "bad big block" with all that torque = incredible amount of tire spin...

Like I said, only building this block because I have it. If I had a 63 block I'd just build that...but i dont

Sorry to point out though, your opinion on the block build was not asked for really...simply the questions pertaining to using the 2.4 block and the accessories of the 2.0, thank you for your info.
 
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