High Compression questions... - Honda Prelude Forum

LudeDrew · 09-11-2002, 11:50 PM

I am sure some others are thinking the same question as I am from time to time.

What are the benefits to running higher compression?

What runs cleaner? Higher or Lower compression? (for the cali people)

irishpilot · 09-12-2002, 12:15 AM

Well the benefits are pretty strait forward...more power through the ENTIRE powerband. Which is nice especially when your doing the city driving that you would have in cali! Now as for cleaner for smog?? that I think wouldn't really change much unless you were to change the fuel maps around with a A/F controller??

I have a H23 am I am going to go with a little nitrous for now..but when my Lude which is at 150k now, hits a point where it needs rebuilt then I am going to resleeve, go with JE 11.5:1 and balance the crank and all that fun stuff and have a NA beast!

If you are looking to add some power than you could also go this method. Only problem is downtime if you dont have a extra car or block sitting around!!!

irishpilot · 09-12-2002, 12:19 AM

Also... a turbo is a amazing device to have under the hood and hearing it windup on its way to redline is a thrill in its self but
dollar for dollar...A turbo setup can setyou back at least $5000 depending what you have now! SO when the internals are about
$1500 and some cash for a machinist to do all the special work its alot cheaper...with that said its also nice to have a allmotor setup and smoke some riced out turbo eclipse!!!
peace!

ancient · 09-12-2002, 01:29 AM

Going FI will cost you more, and you must replace alot of the internals also..... The stock pistons on H22A1s (USDM) run at 10:1 CR.... Which is pretty high to add a Turbo onto that, so do actually make it functal you drop it down, there for you need new pistons..... New exhaust manifold.... Plus the turbo... Not cheap....

Realistically speaking you get more out of the turbo, and you will probably get the attention of alot of people when they hear it spooling up as you FLY past them, but to do an all motor NA, and hear that vtec kick in..... It feels just as good.

H23s are easy to turbo too my knowledge anyways, because of their lower compression.

I hear alot of people having problems with their turbos and having to rebuild after 3 months, because they didn't do it right the first time, and resleeve to begin with.... These engines wern't made to be turboed, there for unless your resleeving I guess your taking chances boosting...

Unless you race alot and goto the track, Turbo really isn't the best choice, anyway you put it it reduces the reliability of your engine. Sticking with NA keeps the car more reliable and keeps it as your daily driver.

Just my 2cents probably wrong on some parts.

4thGVtec · 09-12-2002, 07:40 AM

the h23 is 9.8:1 compression. not a huge difference in compression. also the h22 is a stronger motor. i'd feel safer turboing a stock h22 over a stock h23. my $.02

ShadowSonic · 09-12-2002, 07:45 AM

What are some issues you may encounter in doing a higher compression ?? and H22's are hard a$$ 2 turbo so why would u feel safer turboing?

ar5enal · 09-12-2002, 10:32 AM

I'd feel safer turbo'ing an H22 for a couple of reasons:

1. The H22 is basically a de-stroked H23 (same bore, shorter stroke) and has a better rod/stroke ratio. This is good because any forced inductions puts a great amount of stress on the rods.

2. The H22 has oil squirters located underneath the pistons which help to eliminate hot spots on the piston. Hot spots cause detonation. In a turbo application, detonation causes people to lose motors.

3. (and less important)As long as you're spending the piles and piles of cash for a turbo setup..why not be a hog and have VTEC on top?

Just my opinion. I'm planning on doing a moderate N/A build on my H22 and then spraying N2o.....not enough money for a turbo.

93VTEC · 09-12-2002, 08:31 PM

A well built and well tuned turbo car is far more reliable than an all motor high compression car. The all motor car has the same compression under all circumstances. The turbo motor has relatively low cylinder pressures unless you are accelerating hard. The engine isnt under constant stress.

brendon2k · 09-12-2002, 11:02 PM

N/A if you are going for any power is gonna cost a ton of money veetec spend over 10k on his all motor set up. As far as turbo the h22 doesn't have too many advantages. The rod/stroke ratios is better but that allows it to rev higher. The h23 has a lower powerband and can spool a turbo faster. A h22 is harder to tune due to vtec but some motors at some boost the h22 will have more hp just not that much more.