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HondaBoy
01-12-2008, 05:04 PM
well since i've got a new car now, the 3gee is just sitting there. i have the head off and still need to get it checked out for cracks and whatnot. anyways, i dont want to go this far and not do something to the head. i'm wondering if i should send it off to Gude or another performance company and have it fixed up for me. there are a few machine shops here that do performance enhancement to cylinder heads but mostly of the domestic type.

here's what i want to do. 272 delta cam, stiffer valve springs from paeco, possibly port match the header and head, machine the intake manifold and port match it, already have the 32/36 weber. other than that, i suppose i could use larger valves, probably prelude valves recut to my specs. i'm not touching the bottom end at this point, i do plan to raise the compression slightly with the head being machined, so 93 octane + is going to be needed. that all sounds good to me and is really not too expensive. but, maybe y'all could suggest some more mods i can do with the head. mind you this is the carbureted A20. i may try and get some of this done over the summer. i really want this car back on the road though. i'm just wondering if the auto trans will hold up with much more power to it. being that said, i'll be adding a tranny cooler so not to burn up another one.

coope
01-12-2008, 06:41 PM
even if they are domestics machine shops they still should kno how to work on improts heads same principle

2oodoor
01-12-2008, 08:38 PM
even if they are domestics machine shops they still should kno how to work on improts heads same principle

true, but some may have to be approached carefully..

If you do a reasonable port and polish, match ports, competition valve job, you should be ok with the single 32/36. Sounds like mine but I dont have a whole lot of head work.. jus a lil..
I am interested in the crank fired ign to, better than any modified dizzy IMO. Plus you get control if you want to "enchance" the fuel charge.
The auto tx may hold up if you dont beat it hard, and get the TV cable set right. It is kinda tricky on mine, I have to be carefull how much throttle I give it a certain times, it will downshift all the way..:gun: I am curious how one would hold up driving sensable.
YOu have to face it , the Accord will not be as fast as your new car, but it will be fun as hell to drive.

2drSE-i
01-12-2008, 09:57 PM
stiffer valve springs are a must with the high duration cam, or you could get titanium valves made and youll be fine (heavier, but less friction...unfortunately way more expensive)

MessyHonda
01-13-2008, 12:59 AM
or just buy mine.....i dont think i will ever use my port and polish head. PM me if you are interested.

2oodoor
01-13-2008, 04:57 PM
stiffer valve springs are a must with the high duration cam, or you could get titanium valves made and youll be fine (heavier, but less friction...unfortunately way more expensive)

I am leaning towards disagreeing with that. Stiffer springs you need for high rpm valve float prevention, not supposed to be an issue with A20's. I would however, if I had the moola at the time, put new stock springs in with the cam, but it could be done later as you go. Then again your advice is right on for the question, if you are going all the way, just do it. Another option is A18 prelude double valve springs, probably the way I would go instead of aftermarket, unless of course you have chevy oversize valves/guides machined to fit and punch out the seats as much as possible. (reasonably)

Ichiban
01-13-2008, 08:16 PM
or you could get titanium valves made and youll be fine (heavier, but less friction...unfortunately way more expensive)

I was just curious how the hell titanium is heavier than steel, and why ti valves have less friction. None of that makes any sense to me.

stat1K
01-13-2008, 09:29 PM
titanium would never be heavier than steel just by the sheer properties of the metal alone...

2drSE-i
01-14-2008, 05:49 AM
did a little re-reading in a book, Titanium valves would be lighter, my bad, but this book says that they prevent friction....im not sure how and it really doesnt make sense to me. Im starting to doubt this book i bought because valve float only happens because of high lift, duration has nothing to do with it...

cygnus x-1
01-14-2008, 11:21 AM
Valve float occurs when the spring is not strong enough to close the valve fast enough. As RPMs increase the valves have to open and close faster and faster. Opening is not an issue because the cam just forces it open faster. But during closing the cam can move out from under the rocker faster than the valve spring can push it. So now the valve is partially open when it's not supposed to be. High cam lift would make it worse because now the valve has farther to go before it's closed. Long duration might make it worse too because the valves are already open a long time to begin with.

Having said that, if you don't push the stock redline much there is no need to get stiffer springs. If you want to be safe get some A18 (2g Prelude DX) springs and retainers and use those. You should still be able to get them new from Honda and I bet they aren't that expensive.

I would also mention that your limitation is going to be the 32/36 carb. You will probably still get some benefit from head work but not as much as if you had a bigger carb. It's still worth doing though in case you decide to upgrade the carb later. :)

C|

2oodoor
01-14-2008, 11:43 AM
<<< it is worth doing >>> period.
There are plenty of modified head/cam four cylinder all out race cars running 32/36 webers, not necessiarily drag cars though:)
You have the option to rejet , add spacers or otherwise modify the internals of the carb once you beef up the flow with headwork and cam.
True as it may be, though, yes 38 Downdraft or dual 38 DOCE and higher will net you more grunt.