My H23a is currently sitting on a bench at the moment (spun a bearing!) and since I plan to turbocharge soon (about 10psi with a Garrett T3/4) I figured I would bulletproof the internals while I was at it.
What are some good things to do to strengthen the engine before I run boost?
I had ideas of:
Forged 9:1 pistons (to run lower compression)
new valve springs
maybe new cams?
maybe shot peen the rods?
resleeve?

are there any other good ideas?

 

greyout has some niiice pistons for sale.

 

i rebuilt my h23 for boost but im goin to run 10 daily and turn it up when i race

i have je 9:1 pistons stock bore
sleeved(must)
eagle rods
valvetrain is stock which was recommended
havent got my turbo on yet but its runnin fine now and i have just under 3k miles on it so.
XcreatonX

 

If you want to bulletproof the motor, resleeving is a must. I would go with some nice 9.0:1 CP pistons, eagle rods (if you are on a budget), and OEM rod bearings. There are a lot of people that shot peen their rods, but if you want to bulletproof a motor then go ahead and buy rods that can handle the wear and tear. Since you are only looking at 10psi or so, go with some eagle rods. If you have the money to spend, i would go with the crower 4340 billets.

New cams and valve springs are not necessarily going to help 'bullet proof' your motor, however they will free up some additional horsepower and handle higher revs. The h23a is not a very high reving motor, the most we take mine up to is 7200rpms and that is with stock springs.

The only cams offered for the h23a are either Gude or web cams (http://www.webcaminc.com). Both companies offer regrinds, double check to see if Web has a Turbo camshaft out yet.

p.s.
https://honda-tech.com/zerothread?id=599312
https://honda-tech.com/zerothread?id=596135

I have those for sale if you are interested.

 

If I go with the Eagle rods, sleeving and 9:1 CR pistons, should I retard the timing? or should it be right if I am running 95 octane?

 

XcreationX
How does your car run now that there is a lower CR and no boost?
Reason I ask is cause I want to do the mods now, and the turbo in a month or so... so I am a bit worried that I am going to get whooped by civics!

 

You will be fine with a 9.0:1 compression running NA. Remember, when you get your motor back up and running it is advised to put about 750-1000 miles on the motor before you run boost. Meaning, dont take the motor into boost and dont take it above 3500ish rpms.

As far as retarding timing, buy a hondata and have your motor tuned. Then you will have nothing to worry about.

 

add new injectors, new fuel pump, fuel pressure regulator, and a hondata to that list.

 

Eagle rods stink for boost, trust me from experience, resleeving is necssary but if 10psi is all you want you could get away with out a resleeve on stock internals with a good tune-up.....so look into that before you blow all kinds of money...... lastly, do a search, there's a million topics all about what you need floating around here....... sorry, but i see this post at least once a week..... it gets old

 

GudeH23a:
Do you think that with JE pistons it would be safe to run stock compression and boost?
I got a quote today to do Eagle H beam rods, valve springs, resleeve and JE pistons that were the stock 9.8:1. I told the guy I would do the internals, run the engine in and THEN add the turbo setup. He said that lowering the compression wasn't necessary as long as you used the good quality JE pistons.
I am worried that the Valve train isn't going to like it... Will it be ok though if I get new valve springs and keep a stock redline? Or is lowering compression a DEFINITE to save the engine, regardless of pistons, rods and springs...??

 

Lowering the compression of the engine for a forced induction engine gives you a larger safe range when tuning. Safe range meaning, less chance of detonation.

Keep in mind, lower compression motors will put out a little less hp, but to compensate all you do is turn up the boost (1 compression point equals around 10whp on a NA car, not too sure about FI though). Theoretically a higher compression turbo motor will yield a faster spool up time and be a tad bit quicker off of the line when compared to a motor of a lower compression. It's your call, a lot of people favor the ideal '9.0:1' ratio when it comes to turbocharged honda's and there has been a new trend of guys running 10.0:1 compression lately.

9.0:1 compression is not as sluggish as some people make it out to be. I ran that compression for about 1000 miles NA and I was quite happy with it (keep in mind i did more then just swap out pistons).

As far as your redline goes, I would leave it at stock. The prelude is not a very high reving motor and does not produce that much power past a certain rpm limit, reguardless of running a lower compression or not (hypothetically speaking). I would recommend spending your money on having some head work done (port and polish, 5 angle valve job, ported intake manifold, larger throttle body).

And as for JE pistons go, I am not a fan of them anymore. Their name has been tossed around like a $5 dollar hooker, and in my opinion not worth the 5 dollars at all. I have switched to CP pistons and I have been VERY pleased with the quality and craftsmanship of the pistons. I would call Race Engineering and speak with John if you want to check on CP pistons or even Eagle rods (561.533.5500). They have very good prices.

And as far as a key to saving an engine, the key is to have a good engine management system. End of story. You can run the most expensive parts in the world, but if your motor is not tuned then it probably wont last any longer then 1-3 days if you drive it hard. I strongly recommend the s200 hondata unit for boost.

 

you can get probe rods for the h23 and there better then eagles with bigger bolts

 

I didn't know Eagle came out with rods for the h23a now??

 

I have some nice pistons and a nice manifold for sale if you are interested

 

Got the manifold covered (hopefully) and the pistons I want 87mm stock bore with higher c/r. Thanks anyways

 

I ment for the original poster