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1G 2.3L - Cams, Turbo, and Compression Questions

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Mifff

10+ Year Contributor
30
1
Aug 16, 2012
Colorado Spr, Colorado
Goals - 450hp daily driver on pump (91 in Denver)
Head parts investment - Kiggly race behives, engnblder standard sized valves.
6-bolt block investment - Kiggly Girdle, arp mains, arp "L19" headstuds.

I took my head to a shop here in Denver (Heads by Drew) and Drew really seems to know his stuff. He mentioned to me that he really liked to perform the full head assembly and that I would need cam shafts. My original thought was to use Delta regrinds but he mentioned those would need to be shimmed to account for the smaller lobe diameter which got me thinking if I wanted to shim the lifters. This came as a little bit of a surprise to me as I wasn't planning on getting the cam yet but I need to make progress on the project so now is better than later.

My research has leaned me to at least the 272/272 variety on these cams. I know twicks69 is using 292 cams but I don't intend on making that kind of power so i'm asking if a 272 is my cam or should I look at something else for 450hp? I know this isn't a really good question to ask without knowing the turbo so naturally that segues into the next question.

It's time to select the turbo for this build. I have read that a HX35 or HX40 is a very solid performer in this realm. I would like to use a FP race manifold to simplify the installation so I believe that means I needs a BEP .55 A/R housing, with this be a restriction to reaching my goals? What would be an equivalent FP turbocharger (or turbo in general) for this HP goal?

Finally, I recently created another thread asking if my used pistons were okay (once refurbished) to put back into service. The opinion was that I could go that route but it might be less headache to just purchase new rods/pistons which is the direction I decided to go. The question is many have said that 8.8 compression might make the car hard to tune for using 91 and that 8.5 might be better for this application. I was planning on buying a forged piston/rod combo from extreme PSI (manley/weisco) unless there were objections. The main thing i read about the difference in compression is the better response the higher it is. Is .3 that noticeable of a difference in compression? Should I look at the 8.5 or will this compression factor not play a significant role?

Thank you for all your feedback in advance, sorry to make another "build my car thread".
 
these will just be my opinions

for a 2.3 stroker at ~450 hp, i think your cam choice is good. kelford or gsc s2's i believe would be a good ball park, you could go more aggressive, but if youre looking for DD status, keeping the tq up is the key.

a holset turbo is an awesome performer, wouldnt really be stressed at those levels, but also wont be used to its full potential. however there is alot of room to grow with one.
if its a daily driver/weekend warrior, id look into a 68hta or fp red maybe to help with spool up and under the curve tq. i think the green would be a touch too small. these might be closer to their limit out the gate, but would make good midrange with the aforementioned cams.

on the smaller turbos, i think the higher compression would invite tuning challenges on pump. the larger turbos and housings would give you more wiggle room, but also higher cfm and boost levels can complicate tuning when you get the itch for more power which always happens. personally id take the high compression challenge, but your altitude and turbo choice will make that decision for you more. id say 8.5 to be safe.

im sure someone has more, better suggestions, with more experience and examples. good luck with it!
 
Have you already got the stuff for a 2.3? They tend to not make as much power as they should. Lucas from English racing suggested to my friend to instead do a 2.2 destroker with the 2.4 block.

As for the housing I hear a lot of different opinions from different people. Depending on if you want to street the car or only track it some people want the added lag because it helps a bit with fuel mileage and streetability.
 
For 450hp i think any 272 would work, i made 432hp on mustang dyno with crower cams(probably the mildest 272). Cams are not created equal though. I have Kelford 272s now and its a whole different animal.
I would probably go brian crower 272 they are cheap you dont need expensive valve springs and they are a little more agressive then the crowers.
If your budget is higher Kelfords are the shit but you will need good valve springs too.

my car at that time
8.8:1 2.3L
crower cams
brian crower valve springs
hx40 in bolt on housing 26psi
91oct
conservative tune
i have a dyno graph
 
First thanks for the responses!

I already have a 100mm eagle crank (new) and three 6bolt blocks so I'm invested in a 2.3 for sure, at this point I would prefer not to Introduce the complexity of stuffing a 2.4 block into the DSM though it is intriguing.

Good point by bring up that the housing may help with fuel economy, this will be a street car so I don't want it on boost all the time.

Seems kelfords are the cams for me then. Not that the BC or crower won't work but I have already bought the kiggly race beehives so might as well, especially since there is some break-in thing i might forget on the regrinds and I really dont want to do this again within a year.

Thanks for mentioning your compression and results. I'm still on the fence about the higher compression at altitude. Like tame talon said I might just take the challenge to have it but I'd certainly like to mitigate any issues which could complicate the tune if I can and still get that faster throttle response. Just need to figure out what those are.
 
I don't have hp numbers (never did a dyno), but I run an older Slow Boy Racing 60-1 on my setup and it will spool up ~20psi right around 2800rpm.

If you're looking for a DD turbo, I wouldn't go too big. While the 2.3L helps to acheive (ever so slightly) more power off-boost, turbo lag can get to be a b*tch with the big turbos.

Did you ever figure these questions out? I'm in denver and would love to see what someone else did with a 2.3L....
 
... Did you ever figure these questions out? I'm in denver and would love to see what someone else did with a 2.3L....

Herostar, thanks for the info!

I'm still working on the build, I took a pay cut on a new job so the talon had to get the short straw. I got the head and block done, so it's just assembly (which I imagine will be a huge job). I still have a long way to go but I'll keep you in the loop.

As an fyi I think the guy in the springs I took the block to put 9:1 pistons in. Still a little worried about that but oh well.

No turbo decided on yet so there's still a lot left up in the air.
 
My last build went 9.5:1 2L and hit a wall at 24lbs. Meth in the tb elbow allowed me to push 33 lbs with room, but I didn't want to push the turbo and ran out of injectors. So i tuned to 30. Stock cams atm.

New block is for another eclipse, 2.3L at 10.5:1 gsc s2 cams. Hasn't been installed yet, but I intend to push 40 lbs with direct port meth.

Dont be scared of 8.8... it's almost the same as 8.5. I'd personally go higher.
 
I have never pushed that hard on 91 but here is a dyno graph from my 2.3l, 8.5:1, FP4R cams, .55A/R bolt on HX-35, e85.
I think kelford 272s are a solid cam choice and while the holset works an FP Red or PTE 5558 might be better choices to see the power you want on pump gas.
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