# Throttle Body Sizing for H22A **URL:** \ **Category:** PittSpeed Automotive\ **Created:** [April 14, 2008, 7:16pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833 "2008-04-14T19:16:48Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 14, 2008, 7:16pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/1 "2008-04-14T19:16:48Z")
Motor is a JDM H22A Stock Ignition Stock Intake Mani I/H/E Piecing together a new fuel system with a Walbro 255, new fuel rail, new FPR, slightly upgraded RC injectors, trying to decide on a throttle body. It’s an N/A car and I have no immediate plans to turbo it. I’ve read some anecdotal evidence that an oversized TB can be detrimental to performance so I’m trying to avoid that but I’d like to upgrade a little. There’s an apparent vacuum issue with either my current TB or IAC and I’m in “screw it I’m replacing things” mode. We will be dyno tuning the car after install so the ability of the stock map to cope with the TB is not a concern. I am currently looking at a 68mm TB. Question: Is there a real reason that a 68mm TB would be detrimental or in any way be the wrong choice? ---
**Author:** ![dyingwish](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/dyingwish/32/6041_2.png) [@dyingwish](https://forums.speedlife.net/u/dyingwish)\ **Post date:** [April 15, 2008, 5:43am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/2 "2008-04-15T05:43:32Z")
Yes. An oversized throttle body can affect a few things. If your IM is not port matched to the larger throttle body, then it is doing nothing. If you do match the IM port to the big TB, and the head/cam choice is suboptimal, you’ll do nothing but shift your powerband up to a possibly useless RPM range. Unless your duty cycle values are way up, there is absolutely no reason to put in larger injectors without an intake tract sized accordingly to pull in air, and a head package that allows the use of more flow. Fuel rails are worthless in general, and a bigger fuel pump isn’t going to do anything. If your car is almost totally stock, you aren’t even close to maxing out the OEM delivery system. Is there something your are building towards…that will necessitate the above modifications? ---
**Author:** ![imported\_gearhead](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_gearhead/32/5957_2.png) [@imported\_gearhead](https://forums.speedlife.net/u/imported_gearhead)\ **Post date:** [April 15, 2008, 5:48am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/3 "2008-04-15T05:48:16Z")
If you are going to TB it, then I’d be looking for a type-s IM to go with it. I know I didnt hook up the IAB when I put the motor in ( 👼 ), so might as well get a less-complicated piece in there. ---
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 15, 2008, 7:00am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/4 "2008-04-15T07:00:00Z")
I don’t have any illusions that my motor is overtaxing the capacity of the stock fuel system or the flow properties of the intake. I have intentions of PnP/building with Type S cams in the head and next year doing a low boost turbo, so the parts are serving two purposes for me, replacing a couple of parts that are currently suspected of intermittent failure while also making some provisions for future fuel/air demands. 68mm is the smallest aftermarket TB I’ve been able to find at a decent price, I’m just trying to confirm that it won’t be detrimental if I run it prior to the head upgrades. If the answer appears to be yes I’ll just get the stock TB cleaned up or rebuilt and look at a larger bore later. ---
**Author:** ![dyingwish](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/dyingwish/32/6041_2.png) [@dyingwish](https://forums.speedlife.net/u/dyingwish)\ **Post date:** [April 15, 2008, 7:06am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/5 "2008-04-15T07:06:42Z")
It may be nominally deterimental, but if you are going to need it in the near future then go for it. Domination bores TB’s for a great price…so that is an option as well. ---
**Author:** ![Hycomp](https://avatars.discourse-cdn.com/v4/letter/h/d6d6ee/32.png) [@Hycomp](https://forums.speedlife.net/u/Hycomp)\ **Post date:** [April 15, 2008, 7:18am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/6 "2008-04-15T07:18:59Z")
> [@FS: 2000 Honda S2000 -New Price-](https://forums.speedlife.net/t/fs-2000-honda-s2000-new-price/35941/12): > > It’s an N/A car and I have no plans to turbo it. > [@07 vette not tunned by new era](https://forums.speedlife.net/t/07-vette-not-tunned-by-new-era/35948/13): > > I have intentions of PnP/building with Type S cams in the head and next year doing a low boost turbo. :doh: The bigger bore TB should not hurt as long as you are not going totally overboard on the sizing. ---
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 15, 2008, 8:03am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/7 "2008-04-15T08:03:05Z")
> [@FS: 2000 Honda S2000 -New Price-](https://forums.speedlife.net/t/fs-2000-honda-s2000-new-price/35941/12): > > Motor is a JDM H22A > It’s an N/A car and I have no immediate plans to turbo it. :eek3: Fixed that. ---
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 15, 2008, 8:15am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/8 "2008-04-15T08:15:39Z")
The H22A is 60mm from what I have read. The TB I’ve been looking at is listed for the ITR (which is 62mm stock) but at least a couple people are running it and it’s supposed to bolt right on. I know Skunk2 TBs are cross listed for every Honda engine family (B/D/F/H) so it seems any Honda TB should bolt up. I just foudn a 65mm TB that seems like it would be a good compromise between stock and the more common 68mm stuff. I have heard good things about some “Maxbore” guy in Florida as well, though the price is not much less than a new TB. I will have to look into Domination’s bore service. Have you used them, Steve? I assume they cut a new butterfly and everything? ---
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 15, 2008, 8:32am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/9 "2008-04-15T08:32:26Z")
> [@Intro, but not really.](https://forums.speedlife.net/t/intro-but-not-really/35848/16): > > If you are going to TB it, then I’d be looking for a type-s IM to go with it. I know I didnt hook up the IAB when I put the motor in ( 👼 ), so might as well get a less-complicated piece in there. I have read (on the always reliable internet) that H22’s are very “picky” about intake manifold changes. There are dyno charts showing that the Skunk2 IM actually makes less power on a stock head. Supposedly Skunk2 recommended over the phone that the IM only be used for raised comp/turbo/engines with head work. Still looking for a direct comparison with the Type S intake. T-minus 2 months before I buy an H22 block from JTech and start building something stupid. ---
**Author:** ![dyingwish](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/dyingwish/32/6041_2.png) [@dyingwish](https://forums.speedlife.net/u/dyingwish)\ **Post date:** [April 15, 2008, 9:04am UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/10 "2008-04-15T09:04:39Z")
I have personally seen some of Dominations (Jay) work and it is very nice (say it like Borat). I haven’t used them personally, but I have used OEM re-bored units in the past from Maxbore. Either way it worked…Domination is closer and cheaper. I have heard stories about H22’s touchy intake nature before, but I have a hard time swallowing it…not sure what to say about that since I don’t own/drive an H. I would not mess with it right now. Leave it as is, and upgrade later when you have the mod support for it. You still have plenty of room to make power before that becomes a restriction. ---
**Author:** ![fmfkid250](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/fmfkid250/32/5973_2.png) [@fmfkid250](https://forums.speedlife.net/u/fmfkid250)\ **Post date:** [April 15, 2008, 6:19pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/11 "2008-04-15T18:19:52Z")
I made 500whp on a stock GSR TB. it would be one of the last things i would change. ---
**Author:** ![PoisonousBeef](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/poisonousbeef/32/6007_2.png) [@PoisonousBeef](https://forums.speedlife.net/u/PoisonousBeef)\ **Post date:** [April 15, 2008, 7:45pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/12 "2008-04-15T19:45:56Z")
Ok well with all that has been said I guess I’m just gonna clean up my stock TB for now. Thanks for the input. ---
**Author:** ![imported\_gearhead](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_gearhead/32/5957_2.png) [@imported\_gearhead](https://forums.speedlife.net/u/imported_gearhead)\ **Post date:** [April 15, 2008, 10:22pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/13 "2008-04-15T22:22:59Z")
> [@Beast just came home from work...](https://forums.speedlife.net/t/beast-just-came-home-from-work/35943/21): > > I made 500whp on a stock GSR TB. > > it would be one of the last things i would change. I bet it would have made 520 with a bigger tb 😃 ---
**Author:** ![fmfkid250](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/fmfkid250/32/5973_2.png) [@fmfkid250](https://forums.speedlife.net/u/fmfkid250)\ **Post date:** [April 16, 2008, 3:05pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/14 "2008-04-16T15:05:28Z")
> [@gearhead"](#): > > I bet it would have made 520 with a bigger tb 😃 and 600 with cams…tell me about it go ahead like i dont know :blue: ---
**Author:** ![imported\_gearhead](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_gearhead/32/5957_2.png) [@imported\_gearhead](https://forums.speedlife.net/u/imported_gearhead)\ **Post date:** [April 16, 2008, 6:49pm UTC](https://forums.speedlife.net/t/throttle-body-sizing-for-h22a/196833/15 "2008-04-16T18:49:45Z")
🤣 coulda woulda shoulda