Is there any difference

[Sarthos]

Between the JDM h23a intake manifold and the USDM h23a intake manifold? I won a JDM one on ebay for really cheap, will it work the same as the USDM one, or does the JDM one have a bigger throttlebody or better flow or anything? I know JDM tends to have slightly better parts, so that's why I'm wondering.

[pedroalcala]

H23 Intake manifolds should be the same, the JDM h23a was DOHC Vtec bluetop.
And USDM h23a was DOHC non-Vtec, I think the manifold should be the same....how much did you get it for?

[Sarthos]

$44+ shipping. Includes everything. But I know the JDM one is the vtec version, that's why I was wondering if it needed a higher flowing manifold or something like that.

[almostJDM]

no they are different, the vtec h23 mani is the same as the h22 mani, and it wont bolt up to a non-vtec h23, or f22

[Sarthos]

So the vtec h23a manifold requires f22a6 runners or non-vtec h23a runners?

[pedroalcala]

You can probably put together the lower plenum to the upper plenum....if you bought the h23a vtec version....it will definitely not fit....later

[Father Time]

So the vtec h23a manifold requires f22a6 runners or non-vtec h23a runners?

Yes.

JDM H23 VTEC runners will not bolt to a USDM H23 or F22A head. You can swap the plenum and throttle body over to a set of USDM H23 or F22A6 runners and be good.

[Sarthos]

Darn, I might have been able to go cheaper had I known that. Oh well. Will the throttlebody be too big for my F22A1 motor though? I know people with oversized throttlebodies tend to lose power.

Edit: Is there anything anyone would recommend doing to it once I get it to maximize any power increase? I'm gonna get the Bisi intake manifold gasket, and polish it to make it further reflect heat (or just to be shiny and distract me) but should I also completely disassemble the intake manifold and clean out any carbon build up, add a throttle body spacer, or a thermal throttle body gasket, or anything?

[Sarthos]

Bump since I won't have internet the next 4 days. I don't know if the throttlebody on the new IM will be from an auto or a manual, I didn't realize it mattered. Can I just switch out the throttle rotor if it's from a manual, since my car is an auto?

[almostJDM]

Bump since I won't have internet the next 4 days. I don't know if the throttlebody on the new IM will be from an auto or a manual, I didn't realize it mattered. Can I just switch out the throttle rotor if it's from a manual, since my car is an auto?

yes you can, but make sure when you put the manual one on you wind the spring up so it hold the throttle blade closed

[Sarthos]

I'm putting the auto one on though.

[almostJDM]

I'm putting the auto one on though.

oh, guess i mis read it wont make a difference

[Granite CB7]

Be sure to measure the bore of the t/b, both ends, just to see what you have. I would def. have the t/b bored out, the F22A def. will respond well. Plenum match would be good, but you can EASILY DIY. I would def. do a full inside clean out, even some port work, at least clean up the casting on the inside. If you're going to run EGR, clean the ports and tap for set screws, if not, leave it alone, or clean just incase. Bisimoto's IM gasket is a nice piece Don't bother w/ a phenolic t/b gasket, the source of heat is from the head, hence Bisi's gasket. Throttle body spacers don't seem to do much for Honda's but you could, to put this very simply, the longer you make the IM, the more torque you'll get while losing some high end HP. I would make it as short and direct as possible by deleting the IAB plate all-together, but do some research on that since you need to decide. But def. be sure to grab either PT9 or P14 runners for your F22. Lastly, figure out which idle valves you want to run or block off, getting rid of heat by blocking coolant lines can help your overall cause for keeping things cool but then again, you're going to reinvent what Honda put in place! There is so much you can do w/ just an IM, it's almost endless.

[Turbocutlass]

Darn, I might have been able to go cheaper had I known that. Oh well. Will the throttlebody be too big for my F22A1 motor though? I know people with oversized throttlebodies tend to lose power.

Edit: Is there anything anyone would recommend doing to it once I get it to maximize any power increase? I'm gonna get the Bisi intake manifold gasket, and polish it to make it further reflect heat (or just to be shiny and distract me) but should I also completely disassemble the intake manifold and clean out any carbon build up, add a throttle body spacer, or a thermal throttle body gasket, or anything?

maybe i read over it some where but he said he has the A1.. the A1 manifod does not have the iab's and the h23 vtec manifold will be no good for him.. im suprised no one caught this...

[Granite CB7]

In some of the prev. posts, the OP is aware of the runners not bolting to the head and needing either A6 or H23A1 runners. I think he was just simply stating what motor he's starting w/. Aside from the windage tray, my F22A6 is barely an F22A6