alright so this kid in my collage class thinks that bolting on a 80mm throttle body is going to give his f22b2 better breathing at higher rev's

but is 80mm abit over kill? i thought +70mm tb's were for forced induction applications or am i wrong?

 

80 is way too big. most big all motor guys done even run tb's that big. on a stock motor the stock tb i just fine.

 

Considering Corvettes with 6.2L engines use a 90mm throttle body bore, I would think 80mm on a 2.2L engine would be just a little overkill.

 

Sounds like the kid in your class doesn't understand that there are limits to performance mods depending on engine size and use. He probably thinks that putting the biggest turbo on your car that you can also will directly result in the best power.

In short, he is wrong.

 

Haha. Straight up FAILURE. 65MM would be best for his I/H/E setup; especially for a 2.2L SOHC Non VTEC.

 

Good to know that you go to collAge hahahha

That said, engine modifications are always proportional..
As such, having such a big throttle body with everything else stock will do nothing... You wont get air more air getting to the TB, and with a stock intake manifold you wont get much more air flowing from it..
Finally, the motor itself will probably never require the volume of air that an 80mm TB can handle

 

figures haha, well these were the words from the kid in my class that buys worthless stuff of egay and 'universal jdm domains'

thus why mod a f23a when you could frop a f20b or a h22a in instead

 

Well let's not get carried away here.

The F23 is actually a good motor and pretty stout for boost (iron sleeves, good girdle, etc.) and can be combined with the H22 head if the F-series heads just aren't cutting it for you. This of course also gets around having to resleeve the H22 blocks because of the FRM lining.

Plus using the F23 also saves you on the budget end as well. No big reasons to swap for the H22 or the F20 unless you just want the stock-for-stock power upgrade that brings. You can make plenty of power boosting the F-series.

 

is the f23b block lighter as well?

jw cause my f22b is starting to knock after 290k and looking for a lighter replacement

 

it would be my guess that the H-series would have a lighter block with the FRM liners compared to the F23's iron liners. i think it's safe to assume that there's no significant weight difference between bare F-series blocks. they are all relatively light though when you get the balance shafts and rotating assembly out of them.

 

The F23a1 is probably around the same weight as the F22a's and F22b's.

The H22 shortblock is about 123 lbs.

Unfortunately I can't find my weight data for the F23 I had. I'll keep looking.

 

The extra weight on the H motors is in the heads/valvetrain. Compare the two castings. DOHC castings are enourmous when compared the the Fseries single cam heads.

 

oh yeah, i know! that's why i compromised and stuck with the F22 head on my motor.. extra couple inches of hood clearance. but the bare block is nearly the same.

 

I needed to clean up the garage anyway... here are some weights of things i've got laying around.

bare block [F23A1]: 59.2lbs
crankshaft [F23A1]: 36.8lbs
main caps and bridge/girdle [F23A1]: 16.2lbs
head w/ valvetrain and cam [F22A4]: 42.6lbs

that totals 112 for the bottom end... add 5lbs for pistons and rings... estimated 15lbs for oil pan, pump and pick-up...132lbs.

add in the head and valvetrain: 174.6lbs for an F23A1/F22A4 short block combo.

for kicks/comparison...

bare block [D15B2]: 36.2lbs
crankshaft [D15B2]: 23.6lbs

 

F23 loves boost!

 

Nicely done sir. Apparently I deleted my F23a1 weight specs so these are my new ones haha!

Btw, guess I should reference where I got my H22 short block weight:

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/settle-h22-vs-b-series-weight-arguement-i-bring-you-pics-684550/

You can see in the picture most of what that consists of (and if you read through you can find more details). Btw, the H22 that was weighed has a closed deck and the balance shafts are not in it fyi. You could very well be right about the H22 being lighter.

However OP, the main point that should be explained is that the weight difference should be the least of your worries when it comes to choosing between the two. The difference doesn't end up being that much on the street, and the choices between iron and FRM sleeves (among other things) take a higher priority.

 

So getting back to the original topic, what is the stock TB side on the F22B2? 60mm?

When would it be considered necessary to upgrade to say 65mm or possibly even 70mm?

In my case, I have the usual I/H/E and am about to do a level 1.5 bisimoto cam and tune.. Also, will consider porting and polishing the head within the next year or so..
What would be a good throttle body size for me in this case?

Also, what are the potential downsides to doing this besides reduced intake velocity.
I'm assuming that for small diameter increases, you bore out the current TB as opposed to adding a bigger new one?
Assuming a new, larger one was added however will there be any fitment issues to either the intake or intake manifold?

 

i put the stock tb on a flow machine at my collage vs a 75mm aftermarket one was a massive diffrence, i didnt measure the stock tb but i wanna say 60 or 62mm
i see no reason to upgrade from the stock tb bc like said earlier, there isnt any increased airflow that could cause the stock tb too be too small unless on turbo or s.c applications

 

you're mom goes to college... lol

 

I think you will be fine with the stock TB for the power levels you will most likely be looking at.

The F22b1 I believe is around 57mm at the front, 53mm at the back. The H22 TB would be a good upgrade if you were so inclined. I believe it measures 62mm in the front, 58mm at the back.

Try and stay OEM if you can, as they will be easier to bolt up AND you won't be as likely to experience gasket or pedal-feel issues.

 

i've yet to find a chart or "calculator" or good rule of thumb for TB sizing. maybe there are just too many variables..

what i would suggest is to dyno with the stock sized TB and log the manifold pressure/vacuum. if it doesn't start to drop before red line (along with the torque curve) then it's big enough. if it does drop, increase the size incrementally until you get the desired results.

 

Here is the thing about engines, and we can debate about throttle body sizes and cone filters and headers and flow all day long. But, in an engine, or any system that moves fluid for that matter. The system is only capable of flowing as much air as it's most restrictive part.
For example having a throttle body that can flow 400 cubic feet per minute is useless if your valves can only flow half that.

If you really want to determine the correct size throttle body, you need to see how much your heads flow and then select one accordingly.

 

yes, very good point. this is valuable info that anyone intending to make any performance upgrade(s) needs to be aware of.

but, even guys with degrees in and backgrounds/experience with fluid dynamics only end up with a theoretical number (minimum TB diameter) after all the calculations. it still needs to be confirmed with real world testing and measurements, like on a dyno...

 

Heh, and most people skip the calculations and go straight to the dyno anyway.

Speaking of real world testing, nicolaselias I know AFAccord has several threads on here dealing with his mildly built F-series (F23a1, but it should be close enough to give you an idea).

Here's one:

https://honda-tech.com/forums/showth...&highlight=f23

If you look through his info I'm sure you could get a better idea of what you are up against. You can see he hit a wall with his stock TB and IM, but he is running a bigger cam and there are other variables at play.