8 replies to this topic

[HYP04]

After having the EVO3 Cam'd and turbo'd up recently and the idea for a little while of doing the bottom end. Thoughts of a higher reving 4g engine have been playing on my mind. And with a track day found myself either downshifting and loosing speed or being slightly off boost keeping in gear. Dont get me wrong the car goes good but Id like better (as we all do).

I was initially thinking 2.3 due the use I want to use the car for and spread of power is what Im chasing.
1.Either stretch the power band with a forged bottom end 2.0 engine, with similar to what I have now low end power, but higher rev range upto or 8000+ but then possible gearing issues with tracks plus syncho issues with shifting high to stay in the meat of the power range.
2.Or a 2.3, better power down low, increased spool response, although the possible limitations on RPM and the torque(possible gearbox issues) of the 2.3 may or may not be what Im looking for for longevity.

Than started thinking of a compromise and found the 2.2 with 94mm crank, 150mm rods, 86mm pistons. Still have the possible rev due to piston speeds and added spool????
Only minimal threads I have found thus far and no pre 2.2 and after 2.2 dyno results on torque/rpm curves. It could be taken as a given that with capacity comes spool response, but how good are these things reving with piston and rod speeds?
Tomei do the same kit but have found the following from
http://www.dsmtuners...-99-7-bolt.html
CP Pistons makes pistons for this exact set-up found here at MAP.
CP Pistons 4G63 94mm Stroke 9:1 Pistons - Modern Automotive Performance

Eagle 94mm crank.
EXTREME PSI : Your #1 Source for In Stock Performance Parts - Eagle Forged 4340 Chromoly Stroker Crankshaft (94mm): Mitsubishi Eclipse 92-99 7-Bolt

Any 150mm rods.
EXTREME PSI : Your #1 Source for In Stock Performance Parts - Manley Performance H-Beam Steel Connecting Rods: Mitsubishi Eclipse 92-99 7-Bolt

There is a 156mm rod with Piston 6mm higher pin but had the issue. Manley do a complete kit for the above also.
Could it a good thing, or is there a reason why most have gone the 2.3?

Thanks for any input.

[hendo]

I was looking into this for a while but never realy went any further alot of people seem to do it in the UK, i have a set os second hand pistons in great nick if you want them

[DOUGMO]

i would go the 156mm rod on that crank personally. but thats my preference I guess.

steer well crear of eagle cranks, look at ARD/maxspeedingrods maybe? or K1

http://www.ebay.com....=item5d30566b39

The manley rods are ok but heavy.

a 2.3 does offer a lot more down low though just due to the longer stroke, even better go a nimbus 4g64 block
And a 2.3 also has the high pin so wont be much different on a 2.2 with a 156mm rod.


The 94mm crank definatley allows the engine to rev more freely with slightly lower piston speeds, the car I drove at WTA last year had the tomei 2.2 kit and sung to over 8000rpm no problem, I personally wouldnt rev a 2.3 much over 7000rpm (but people do)

Edited by DOUGMO, 23 October 2012 - 08:55 AM.

[ENGINR]

I initially went the 2.3 route because I was able to get my hands on a 6-bolt 4G64 crank and use that in my spare 2.0 block. The car was originally going to be a daily driver so I wasn't worried about high rpm etc. I wanted a daily with a tonne of torque, not a high rpm race engine.

BUT! I've had no issues tracking the thing and (touch wood!!) it's held up fine throughout a few track days and dyno tunes. We inspected a rod and piston and checked the bores when we had it apart earlier in the year and everything was wearing perfectly. I love the punch and throttle response the 2.3 gives, I'm hanging to see how it goes with the GTX3076 I've installed. With the high flowed TD06 I had on it earlier, I could stay in 3rd gear around corners that others had to drop into 2nd for.

My next engine build will be using a G4CS block and will either be built as a de-stroked 2.2 (believe it uses the 94mm crank) or a straight 2.4 long rod like Baz's setup. Still undecided.

Edited by ENGINR, 23 October 2012 - 11:06 AM.

[HYP04]

Thanks for the replies. I will what I can find in the way of the 156mm rods.
I didnt realise there was such a weight difference for rods....

[bazeng]

Weight isn't a bad thing as long as they don't break imo...

[Liberoz]

I'm with Dougmo on the "nimbus 4g64 block" combo

[HYP04]

At the moment I dont think I'll look at the 4G64 option as finding a Nimbus block here would be near impossible.

[spanku]

At the moment I dont think I'll look at the 4G64 option as finding a Nimbus block here would be near impossible.

Underwood Wrecking - $250 (If I remember correctly) - suit rebuild.