Mine went pop. Looks like a low oil issue.

I've been told that a rebuild with forged internals would allow me to run whatever compression I like. What should I aim for with a Comptech blower?

I also have the option of a 2.3L upgrade. What CR should I look at on this?

What sort of boost levels could I then run?

Just looking for a bit of advice, as knowledge is thin on the ground in the UK.

Cheers,
Ben.



(My engine is JDM, so a 11.7 CR as stock, I've 750cc injectors and an AEM ecu, so that's sorted, Spoon clutch so that's fine).

 

Personally, I am so partial to the OEM 2.0L Honda unit from the factory...it's not like you're running a 20 psi turbo setup. If you want to run a higher boost setup (say 14psi through the Comptech), there are guys running the factory motor with factory compression at those boost levels and tracking the car (see JohnZ), but I'd just slap on an Inline Pro 3mm HG with the factory motor and call it a day. I believe you'll get 9.5:1 compression and the car will pull like a freight train.

Modifry's factory stock CTSC'd motor went something like 180k before the compression got so low that he wanted a new motor. That guy beat the snot out of that setup and it was dead reliable. I think that's longest endurance test anyone has done with a boosted S2000. The factory motors are great and have forged pistons out of the box.

Whatever you decide, just take your time and do it right.

 

Cheers for the heads up.
The rebuild is happening as I've an engine that is clanging like a deisel. So it needs work anyhow.

It was suggested :

I'm currently running 9psi (316whp). And was thinking 16/17psi on a 2mm HG would be awesome, and less stressed.

9.5:1 vs 11.7:1 CR, that's quite a drop.

 

Oh, I forgot you are at 11.7:1 CR stock...in the US we are at 11.1:1. That means your CR with a 3mm HG might be around 10:1...FYI

 

So it'd be best to go 3mm over the 2mm?

 

dont put a
HG buy 10 cr pistons from the piston companies,sleeve the block and put 15psi...CTSC...
or 10.5 cr pistons...
In any case you have to sleeve the block since nobody can do the FRM on the block like Honda does so you cant use OEM pistons anyway..
Buy 400$ pistons,Sleeve the block and dont worry,,,
i say 10,5 cr since i am OEM CR and 15 psi...CTSC.
Cheers...
same thing happend to me and i bought a Brand new Shortblock from honda..

 

last I checked, you can't go any higher then ~14psi as thats as fast as the blower can spin before being damaged.

 

It won't damage the blower...but at anything much above 14psi you are pretty much just creating excessive heat without making more power because you are out of the SC's efficiency range. Same as boosting a turbo more than it was designed to boost...

 

i am partial to lowering the compression thorugh pistons, as opposed to the hg. since yours is fubard anyways, and you need to sleeve the block anyways. 9:1 pistons, truthfully, tossing in 10:1 may net you about 10whp more until boost builds. big deal. 9:1 ftw in a sleeved block.

if not becuase i said so ROFL, look at what each manufacturer does in an oem motor that is boosted.

ford cobra is around 8.8:1
supras where low 8.something:1
srt4 is around 8.something:1
buick gn was around 8.3ish:1 or less
ford lighting 8.4:1


the highest i think i can remeber in a factory boosted car is 9.3ish:1. i think the mazda speed 3 has around 9.9:1 but that thing is direct injection and less rooom for more boost.

 

Actually, all VW 1.8T's have a compression ratio of 9.5:1 and the 2.0T direct injections run a CR of 10.3:1