92 cb coupe drag build questions

[KBA]

Well, that's a topic for discussion. We for sure see ram intakes on almost every pro car, which begs the question why do it if it's not beneficial..
I for one think that it's only when you get up to speed that you start to require the extra power more than ever, simply because your fight with grip is slowly transforming into fight with drag, that is where ram-air comes to your aid.
I think if the system is properly designed, it can get you much more than 0.02 bar (which by the way equals roughly 2% of power increase) on even lower speeds than 60 MPH.
I still have ram intake as one of my pending projects for the supermoto build, and we are only topping out at 70 - 75 MPH on rare occasions. The average speed of a SuMo in our local tracks is ~45 MPH

[Blackcoupe91]

I know on v8s a tall intake equals more power and torque. granted usually higher in the rpm range. I saw a h2b civic with one he said he saw 5% increase all across the board over the golden eagle he had before. and they're both anout the same price, and I'm just gonna run the f20b till the nitrous blows it up and hopefully ill have an h22a with some sleeves and high comp pistons.

[sonikaccord]

I know on v8s a tall intake equals more power and torque. granted usually higher in the rpm range. I saw a h2b civic with one he said he saw 5% increase all across the board over the golden eagle he had before. and they're both anout the same price, and I'm just gonna run the f20b till the nitrous blows it up and hopefully ill have an h22a with some sleeves and high comp pistons.

Long runners shift the power band lower, short runners move it higher.

I think everything on the f20b except internals are similar to the H. Have we ever figured out the exact differences?

[AhYesCB7]

I can barely understand what you're saying. Please use punctuation. You're not texting your girlfriend. You're asking experienced people for help building your car. Please show us the same courtesy we show you. If we can't understand you, we can't help you. Eventually, people won't even try.

If you're getting an f20b, be prepared to order some replacement parts from overseas, since that engine was never sold in the us, and there is no equivalent here. The p72 came from the integra gsr. Make sure it's obd1, or it's useless. You can't use a stock Civic/integra ecu.
I've never seen a front facing intake on any of these engines. I don't imagine they make much power at all. An Accord Euro R intake is generally the best thing for an h22a or anything similar. Beyond that, ITBs.

You can see where my interest ended lol.

I like how hes going to spray the F20B to death, nice.

[deevergote]

Long runners shift the power band lower, short runners move it higher.

I think everything on the f20b except internals are similar to the H. Have we ever figured out the exact differences?

Damn near everything. Different bore. Different stroke. Different cylinder material.
The heads are similar, though the f20b has valves that are 1mm smaller.



Why waste $1000+ on an engine you intend to blow up? Be patient, and just build the h (or even an f22a) properly. An extra $1000 will go a long way.

[KBA]

Long runners shift the power band lower, short runners move it higher.

+1 almost always it does.

Except when you come across a phenomenon called harmonics. When your runner length lies on the crossing between two different harmonics, it is possible to gain more high end power by increasing the length. The same stands for exhaust runner (manifold). However, that is very rare since engines are designed for specific harmonics from the factory.

By the way I can only hang my jaw what people in the states are doing with F20Bs, like they could be found anywhere. Here in eastern Europe (at least in Latvia) we have none, but that would be some killer engine to play with..

[Blackcoupe91]

ok I think I got it figured out and does anyone know a company that makes higher than 11.5:1 pistons for a h22a and can anyone give any comments on 220 racing?

[Rilas]

Here is an H22 with the head reversed. It was done for circuit racing but it is possible with the stock pieces. A little machining was done to the head to make the cams work.



It is possible to reverse the intake and exhaust and has been done on the F20B's as well for either a Euro or Japanese race where the engine was limited to 2.0 litres.

[sonikaccord]

+1 almost always it does.

Except when you come across a phenomenon called harmonics. When your runner length lies on the crossing between two different harmonics, it is possible to gain more high end power by increasing the length. The same stands for exhaust runner (manifold). However, that is very rare since engines are designed for specific harmonics from the factory.

By the way I can only hang my jaw what people in the states are doing with F20Bs, like they could be found anywhere. Here in eastern Europe (at least in Latvia) we have none, but that would be some killer engine to play with..

Helmholtz resonance?

I can't visualize how a longer runner would increase upper end power, by the time the pressure wave bounces back, the intake valve would not be in the best position, maybe closed or not fully opened. I'm speaking more of ITBs than other manifold designs. I'm sure a plenum could have more "crosstalk" between runners.

[KBA]

Well, imagne a runner that has not yet been tuned from factory. The pressure wave will bounce back twice or even three times before the perfect moment occurs, missing it essentially every time. In this case making the runner longer will offset the pressure wave to the desired direction which can be both lower and higher in the RPM. It's just like music. You can play a higher note by going down the griff and it will sound just as good as the same note up the griff. Music and engines do not fall that far from each other

[Raf99]

Not sure how reversing a head is even possible. Distributor, coolant, oil passages, sensors........ ? And a lot of other little things. Seems like a lot of head work would be required, including filling and drilling holes.

[Rilas]

Not sure how reversing a head is even possible. Distributor, coolant, oil passages, sensors........ ? And a lot of other little things. Seems like a lot of head work would be required, including filling and drilling holes.

Oil and coolant line up if I remember correctly. I've read a huge article on how it was done. The real machining was to make the cams work in the head reversed. Obviously some more needs to be done to be able to bolt on the distributor, and other such things.

[Raf99]

This is actually quite interesting. One would have to migrate everything on the side of this block to the other side? But they didn't do that, they made custom holes for the coolant temp sensor, and other sensors. If they kept them on the original side of the head the pipes/wires are in the belts. Even the radiator connection was made, but i think they kept the OEM return i think. Does anyone know what that thing is attached to the backside of the head, and has a 8an line going to the head?

[Rilas]

Its the v-tec solenoid. Look at the top triangle with 3 bolts and the cap on top. Same exact as the top of the OEM v-tec solenoid.

[sonikaccord]

Well, imagne a runner that has not yet been tuned from factory. The pressure wave will bounce back twice or even three times before the perfect moment occurs, missing it essentially every time. In this case making the runner longer will offset the pressure wave to the desired direction which can be both lower and higher in the RPM. It's just like music. You can play a higher note by going down the griff and it will sound just as good as the same note up the griff. Music and engines do not fall that far from each other

They are very, very, close...there is a reason they call it tuning

I had typed up some runner length things, but I don't want to derail this thread too much. I'll just say I believe engine RPM and musical notes(frequencies) play a big part in this.