Need some help with H/F-series piston info. *Searched*
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Need some help with H/F-series piston info. *Searched*
I have been online for the past few days searching my *** off for the piston specs for H and F series engines. Well I stumbled across this very useful thread:
https://honda-tech.com/zero...age=1
However, I am still missing some info. I need the Dome displacements for the H and F series pistons.
Also I have been looking for a compression calculator for the H/F series motors just like all the ones for the B and D-series engines.
Any help is appreciated.
https://honda-tech.com/zero...age=1
However, I am still missing some info. I need the Dome displacements for the H and F series pistons.
Also I have been looking for a compression calculator for the H/F series motors just like all the ones for the B and D-series engines.
Any help is appreciated.
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From: Betonwüsten, USA
Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
H-series is bad enough and you want F too? Good luck. People cannot get organized here it's mostly "fix my CEL" and body kit threads etc. Your best bet is to contact people that have actually spent the time to build an H-series engine. They might know. Or go to http://www.c-speedracing.com/h...c.php and solve for the dome displacement. If you know all the other variables for a particular engine then you can dissect the specifics or get close enough to warrant further time and money in your own research. Is this for your H1 plans?
Pirate
Pirate
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Re: Need some help with H/F-series piston info. *Searched* (PirateMcFred)
Yeah I did some searching last night and found out how to calculate for compression. From the known variables, I should be able to calculate dome displacement. It is going to be a lot of math to solve for all, but I will do what I have to.
You will be glad to know pirate that I may try to build a G23 myself or may see about putting a set of F20B pistons in a B20. I want to build a nonvtec monster for H1, and we know my 172 whp LS isnt going to compete with 220 whp B20/Vtec's, H22's, and K20's that are running around H1. So I am in the planning and price checking stage.
You will be glad to know pirate that I may try to build a G23 myself or may see about putting a set of F20B pistons in a B20. I want to build a nonvtec monster for H1, and we know my 172 whp LS isnt going to compete with 220 whp B20/Vtec's, H22's, and K20's that are running around H1. So I am in the planning and price checking stage.
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Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
Sitting down with a pencil, calculator, a piece of paper and a beer is a far less painful than shelling out $60 an hour for shop services to get piston dome ccs. I would be curious about the F20B's clearance in the B20. I thought that the piston was really tall and heavy... I think I remember an All Motor forum B20Vtec thread with F20B pistons a year ago. Seemed like it had really high compression. That might not be so bad with a nice P8R head since the combustion chamber is slightly larger.
I read through the Honda Challenge rules real quick and I did not see anything limiting the fuel. So can you run methanol and 15:1 compression legally?
Also Honda challenge is road racing right? So, longevity is a large concern. That could be an interesting complication for all these stock rods. I think that the most important systems are the cam, induction and exhaust systems for getting the power you seek. If you went with a F23 block I know that you can get 13:1 compression with JDM Integra (RSX Type-S 11.5:1CR) OS pistons, a F23 overbored to 86.25mm, stock HG, and an unmilled H23A1 head. Mill the head .030" and you can get 14.25:1. So if fuel is unlimited then you can have a bunch of power low, without having to rev the **** out of it with gobs of torque for pulling out of corners.
Of course with that kind of compression you can run pretty aggressive cams. You should go with something custom header and a P&P to match. I wonder how that P8R head and the H23 head compare in flow stock.
Yeah so anyway good luck. It sounds like a fun project.
Pirate
I read through the Honda Challenge rules real quick and I did not see anything limiting the fuel. So can you run methanol and 15:1 compression legally?
Also Honda challenge is road racing right? So, longevity is a large concern. That could be an interesting complication for all these stock rods. I think that the most important systems are the cam, induction and exhaust systems for getting the power you seek. If you went with a F23 block I know that you can get 13:1 compression with JDM Integra (RSX Type-S 11.5:1CR) OS pistons, a F23 overbored to 86.25mm, stock HG, and an unmilled H23A1 head. Mill the head .030" and you can get 14.25:1. So if fuel is unlimited then you can have a bunch of power low, without having to rev the **** out of it with gobs of torque for pulling out of corners.
Of course with that kind of compression you can run pretty aggressive cams. You should go with something custom header and a P&P to match. I wonder how that P8R head and the H23 head compare in flow stock.
Yeah so anyway good luck. It sounds like a fun project.
Pirate
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From: VA Beach, VA, USA
Re: Need some help with H/F-series piston info. *Searched* (PirateMcFred)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PirateMcFred »</TD></TR><TR><TD CLASS="quote">Sitting down with a pencil, calculator, a piece of paper and a beer is a far less painful than shelling out $60 an hour for shop services to get piston dome ccs. I would be curious about the F20B's clearance in the B20. I thought that the piston was really tall and heavy... I think I remember an All Motor forum B20Vtec thread with F20B pistons a year ago. Seemed like it had really high compression. That might not be so bad with a nice P8R head since the combustion chamber is slightly larger.
I read through the Honda Challenge rules real quick and I did not see anything limiting the fuel. So can you run methanol and 15:1 compression legally?
Also Honda challenge is road racing right? So, longevity is a large concern. That could be an interesting complication for all these stock rods. I think that the most important systems are the cam, induction and exhaust systems for getting the power you seek. If you went with a F23 block I know that you can get 13:1 compression with JDM Integra (RSX Type-S 11.5:1CR) OS pistons, a F23 overbored to 86.25mm, stock HG, and an unmilled H23A1 head. Mill the head .030" and you can get 14.25:1. So if fuel is unlimited then you can have a bunch of power low, without having to rev the **** out of it with gobs of torque for pulling out of corners.
Of course with that kind of compression you can run pretty aggressive cams. You should go with something custom header and a P&P to match. I wonder how that P8R head and the H23 head compare in flow stock.
Yeah so anyway good luck. It sounds like a fun project.
Pirate</TD></TR></TABLE>
Would K20 Pistons fit F23 rods? Yes F20B pistons will fit in a B20 when milled 1mm over. I have to re-read the rules to find limitations. The down side to the F20 piston is that they are heavy. And yes I got the idea from that thread where a guy bought the motor from Thailand where it is a common combination.
Also I think the h23 head has more potential as it has larger valves(stock valves must be used). The h23 head has I:34mm/E:29mm valves; while the P8R has I:33mm/E:28mm.
Also wouldnt methanol would be expensive as hell to run b/c I am not rich.
Yeah calculating formulas by pen and paper is time-consuming, however in some ways I find it fun b/c I can theoritcally determine the outcome of different setups.
Feel free to drop me an email and I will let you know what calculations i come up with if you would like to lend advice as this progresses.
I read through the Honda Challenge rules real quick and I did not see anything limiting the fuel. So can you run methanol and 15:1 compression legally?
Also Honda challenge is road racing right? So, longevity is a large concern. That could be an interesting complication for all these stock rods. I think that the most important systems are the cam, induction and exhaust systems for getting the power you seek. If you went with a F23 block I know that you can get 13:1 compression with JDM Integra (RSX Type-S 11.5:1CR) OS pistons, a F23 overbored to 86.25mm, stock HG, and an unmilled H23A1 head. Mill the head .030" and you can get 14.25:1. So if fuel is unlimited then you can have a bunch of power low, without having to rev the **** out of it with gobs of torque for pulling out of corners.
Of course with that kind of compression you can run pretty aggressive cams. You should go with something custom header and a P&P to match. I wonder how that P8R head and the H23 head compare in flow stock.
Yeah so anyway good luck. It sounds like a fun project.
Pirate</TD></TR></TABLE>
Would K20 Pistons fit F23 rods? Yes F20B pistons will fit in a B20 when milled 1mm over. I have to re-read the rules to find limitations. The down side to the F20 piston is that they are heavy. And yes I got the idea from that thread where a guy bought the motor from Thailand where it is a common combination.
Also I think the h23 head has more potential as it has larger valves(stock valves must be used). The h23 head has I:34mm/E:29mm valves; while the P8R has I:33mm/E:28mm.
Also wouldnt methanol would be expensive as hell to run b/c I am not rich.
Yeah calculating formulas by pen and paper is time-consuming, however in some ways I find it fun b/c I can theoritcally determine the outcome of different setups.
Feel free to drop me an email and I will let you know what calculations i come up with if you would like to lend advice as this progresses.
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Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
F23 Block + H23 Head + K Pistons = 
That was another motor I was planning to build when I was considering going all motor... It would be great for auto-x... But I figured the G23 with boost would be good for auto-x too...
That was another motor I was planning to build when I was considering going all motor... It would be great for auto-x... But I figured the G23 with boost would be good for auto-x too...
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From: Betonwüsten, USA
Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
JDM K20A (DC5) pistons in an F23:
(^link to more pics/info) Fastwannabe ran with my suggestion I made in my F23/H23 Hybrid thread last november. He posted his build info and pics in Prelittlelude's F22/H22 hybrid thread.
A couple fastwannabe's pictures (teaser):
He clayed it too with an H22 head without incident. So you can run some really wild nonVTEC cams with those pistons and still have good clearance. Like you say the H23's valves are 34In/29Ex and the H22's are 35In/30Ex
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid_VTEC »</TD></TR><TR><TD CLASS="quote">Also wouldnt methanol would be expensive as hell to run b/c I am not rich.</TD></TR></TABLE>
Well if you plan on using race gas then Methanol might not be that much more expensive. Especially if you bought it bulk from an industrial supplier. I did that a long time ago for toluene, went to the loading dock and got a 55gal drum of it for increasing the octane rating of my gas for track days.
I like the rules concerning head porting for H1. With unlimited porting you can really get the H23 head to flow. However, I do not like the rules concerning intake manifolds.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by section 9.3.1 »</TD></TR><TR><TD CLASS="quote">g) Items (such as throttle bodies and intake manifolds) that attach to the cylinder head may be re-drilled for fitment purposes ONLY. Alteration of air, fuel, and/or coolant passages is not permitted. Fitment
modifications that alter air, fuel, and/or coolant passages as a side effect will be deemed illegal. </TD></TR></TABLE>
When it comes to that it might be worth it to look into redrilling the Euro R H22 IM to fit it on the H23 head. I think that the port spacing is almost the same (if you are interested I can compare some gaskets tonight). but then the H23 thermostat housing does not mount well then... SO a cutom bracket should be made to hold it in place...
In the case of the H23 intake manifold there is a coolant port that should be blocked off that is attached to the #4 runner. It will heat the entire manifold and really hike the air temps on cylinder #4. An insulating manifold gasket with that coolant port blocked off would help. Then you have to reroute the coolant flow to the thermostat but that is pretty easy, just use the heater core plug on the head. and a simple insulating spacer on the thermostat housing should be installed to keep heat from transfering to the IM...
But hey this is just things that I have thought about. It would still be a lot of work and money to make 220+ whp on a nonVTEC and sucessfully compete in H1. A G-hybrid engine would shift the weight bias on the car more than a B-series. I guess it would be a matter of whether or not the suspension could be adjusted to compensate effectively for the shift. You have your work cut out for you Rick.
Pirate
(^link to more pics/info) Fastwannabe ran with my suggestion I made in my F23/H23 Hybrid thread last november. He posted his build info and pics in Prelittlelude's F22/H22 hybrid thread.
A couple fastwannabe's pictures (teaser):
He clayed it too with an H22 head without incident. So you can run some really wild nonVTEC cams with those pistons and still have good clearance. Like you say the H23's valves are 34In/29Ex and the H22's are 35In/30Ex
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid_VTEC »</TD></TR><TR><TD CLASS="quote">Also wouldnt methanol would be expensive as hell to run b/c I am not rich.</TD></TR></TABLE>
Well if you plan on using race gas then Methanol might not be that much more expensive. Especially if you bought it bulk from an industrial supplier. I did that a long time ago for toluene, went to the loading dock and got a 55gal drum of it for increasing the octane rating of my gas for track days.
I like the rules concerning head porting for H1. With unlimited porting you can really get the H23 head to flow. However, I do not like the rules concerning intake manifolds.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by section 9.3.1 »</TD></TR><TR><TD CLASS="quote">g) Items (such as throttle bodies and intake manifolds) that attach to the cylinder head may be re-drilled for fitment purposes ONLY. Alteration of air, fuel, and/or coolant passages is not permitted. Fitment
modifications that alter air, fuel, and/or coolant passages as a side effect will be deemed illegal. </TD></TR></TABLE>
When it comes to that it might be worth it to look into redrilling the Euro R H22 IM to fit it on the H23 head. I think that the port spacing is almost the same (if you are interested I can compare some gaskets tonight). but then the H23 thermostat housing does not mount well then... SO a cutom bracket should be made to hold it in place...
In the case of the H23 intake manifold there is a coolant port that should be blocked off that is attached to the #4 runner. It will heat the entire manifold and really hike the air temps on cylinder #4. An insulating manifold gasket with that coolant port blocked off would help. Then you have to reroute the coolant flow to the thermostat but that is pretty easy, just use the heater core plug on the head. and a simple insulating spacer on the thermostat housing should be installed to keep heat from transfering to the IM...
But hey this is just things that I have thought about. It would still be a lot of work and money to make 220+ whp on a nonVTEC and sucessfully compete in H1. A G-hybrid engine would shift the weight bias on the car more than a B-series. I guess it would be a matter of whether or not the suspension could be adjusted to compensate effectively for the shift. You have your work cut out for you Rick.
Pirate
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pirate, whats the original purpose of that coolant port? is it to warm the car up quicker??
i have to look better into that, i may block it on my 22....
ps check out my thread for dome displacements: haz "click" aqui hehe, un poco espanol para ustedes
i have to look better into that, i may block it on my 22....
ps check out my thread for dome displacements: haz "click" aqui hehe, un poco espanol para ustedes
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Re: Need some help with H/F-series piston info. *Searched* (PirateMcFred)
Thanks Pirate!
Porting isnt unlimited, you are only allowed up to port up to 1 inch into the ports, however I am sure a lot of other ppl have done more than this.
Anyone have teh specs and part number for the RSX Type S K20 piston?
Modified by hybrid_vtec at 12:41 PM 10/21/2005
Porting isnt unlimited, you are only allowed up to port up to 1 inch into the ports, however I am sure a lot of other ppl have done more than this.
Anyone have teh specs and part number for the RSX Type S K20 piston?
Modified by hybrid_vtec at 12:41 PM 10/21/2005
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Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybrid_vtec »</TD></TR><TR><TD CLASS="quote">Porting isnt unlimited, you are only allowed up to port up to 1 inch into the ports, however I am sure a lot of other ppl have done more than this.</TD></TR></TABLE>
For H1:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Section 9.3.1 »</TD></TR><TR><TD CLASS="quote">9.3.1 Hybrid Vehicle Engine Preparation
c) "Above the engine block" cylinder head preparation and porting is unrestricted. Valve size and material must conform to original specification for that particular head. Rocker shaft assemblies are also unrestricted.</TD></TR></TABLE>
Did I misread?
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid_VTEC »</TD></TR><TR><TD CLASS="quote">Anyone have teh specs and part number for the RSX Type S K20 piston?</TD></TR></TABLE>
For USDM or JDM?
Pirate
For H1:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Section 9.3.1 »</TD></TR><TR><TD CLASS="quote">9.3.1 Hybrid Vehicle Engine Preparation
c) "Above the engine block" cylinder head preparation and porting is unrestricted. Valve size and material must conform to original specification for that particular head. Rocker shaft assemblies are also unrestricted.</TD></TR></TABLE>
Did I misread?
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid_VTEC »</TD></TR><TR><TD CLASS="quote">Anyone have teh specs and part number for the RSX Type S K20 piston?</TD></TR></TABLE>
For USDM or JDM?
Pirate
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From: Basin, WY
Re: Need some help with H/F-series piston info. *Searched* (hybrid_vtec)
subscribe to thread.
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?
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Re: Need some help with H/F-series piston info. *Searched* (The_Head)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The_Head »</TD></TR><TR><TD CLASS="quote">subscribe to thread.
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?</TD></TR></TABLE>\
i dont see why not....i believe they accept to the same type of rod....but compression height might be the only issue....im sure pirate will get into more detail
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?</TD></TR></TABLE>\
i dont see why not....i believe they accept to the same type of rod....but compression height might be the only issue....im sure pirate will get into more detail
Thread Starter
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Posts: 4,640
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From: VA Beach, VA, USA
Re: Need some help with H/F-series piston info. *Searched* (PirateMcFred)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PirateMcFred »</TD></TR><TR><TD CLASS="quote">
Did I misread?
For USDM or JDM?
Pirate</TD></TR></TABLE>
I guess I mis-read!(Oppps)
JDM K20 Pistons, but if you have both(specs and Part #) I am willing to expand my knowledge.
Did I misread?
For USDM or JDM?
Pirate</TD></TR></TABLE>
I guess I mis-read!(Oppps)
JDM K20 Pistons, but if you have both(specs and Part #) I am willing to expand my knowledge.
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Re: Need some help with H/F-series piston info. *Searched* (SB tuning)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The_Head »</TD></TR><TR><TD CLASS="quote">subscribe to thread.
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SB tuning »</TD></TR><TR><TD CLASS="quote">\
i dont see why not....i believe they accept to the same type of rod....but compression height might be the only issue....im sure pirate will get into more detail </TD></TR></TABLE>
You can use h22a4 rods because they are floating wrist pin type or have h22a1 rods rebushed but you couldn't use an h22a1 crank because it has 50mm mains... The compression height of F pistons is the same as K pistons so you know they would fit in the block but with H22 rods they might stick out of the block, possibly only enough so that enlarging the quench pads will be enough... I don't have all my h/f specs saved on this comp otherwise i would do the math to try and figure it out...
This is giving me ideas tho..
H22A Head
F23A1 block
H22A4 crank/rods
K20A2 pistons
Best thing about it is you dont have FRM to bore out. It's hard to find someone in my area that can do that.
Will K pistons go on the H22 rods?</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SB tuning »</TD></TR><TR><TD CLASS="quote">\
i dont see why not....i believe they accept to the same type of rod....but compression height might be the only issue....im sure pirate will get into more detail
</TD></TR></TABLE> You can use h22a4 rods because they are floating wrist pin type or have h22a1 rods rebushed but you couldn't use an h22a1 crank because it has 50mm mains... The compression height of F pistons is the same as K pistons so you know they would fit in the block but with H22 rods they might stick out of the block, possibly only enough so that enlarging the quench pads will be enough... I don't have all my h/f specs saved on this comp otherwise i would do the math to try and figure it out...
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