F24 Build
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FYI, Looks like K1 already have S2000/K24 rods conversion, all we need is Mahle to come up with FRM friendly pistons with proper valves cut out and various CR choice...
Or may be the stock S2000 pistons can be re-used, the rod is .006" shorter than the H22...I would ask K1...
Edit: the K1 rods have a 22mm wrist pin ID and the S2000 pistons have 23mm ID if I'm not mistaken, can somebody confirm that?
HH5630AEGB4 Honda Honda S2000/K24 Conversion Rod 5.630" 2.008" 22mm 3/8" 526
http://www.k1technologies.com/Portals/0/Do...ompact_Rods.pdf
Cheers
Or may be the stock S2000 pistons can be re-used, the rod is .006" shorter than the H22...I would ask K1...
Edit: the K1 rods have a 22mm wrist pin ID and the S2000 pistons have 23mm ID if I'm not mistaken, can somebody confirm that?
HH5630AEGB4 Honda Honda S2000/K24 Conversion Rod 5.630" 2.008" 22mm 3/8" 526
http://www.k1technologies.com/Portals/0/Do...ompact_Rods.pdf
Cheers
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Joined: May 2002
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From: Raleigh, NC
the problem with using 5.630/5.636 inch rods is that it would require a very tall piston, generally the taller the compression height the less stable the piston is in the bore, this also makes the piston heavier.
In general, most aftermarket h22 rods are the incorrect 5.630" length instead of the proper 5.636 inch length.
My contact at mahle said they have done the development on the f20c application and they have a very nice forging for this app, just no extra money to put into production at this time. It is still considered a custom application. Custom mahle's run about $200 each with about a 6 week turnaround time. Thats about $150 more than a standard shelf set of the gold series pistons.
the stock f2xC motor does have a 23mm pin, just about every other honda has a 22mm pin.
and after looking around the k1 website and some quick googling, toyota 2az-fe rods will work on the k24 crank with no modifications and result in a slightly taller CH of 1.004. That and the smaller pin would make that rod ideal if it keeps the pin out of the oil ring land
In general, most aftermarket h22 rods are the incorrect 5.630" length instead of the proper 5.636 inch length.
My contact at mahle said they have done the development on the f20c application and they have a very nice forging for this app, just no extra money to put into production at this time. It is still considered a custom application. Custom mahle's run about $200 each with about a 6 week turnaround time. Thats about $150 more than a standard shelf set of the gold series pistons.
the stock f2xC motor does have a 23mm pin, just about every other honda has a 22mm pin.
and after looking around the k1 website and some quick googling, toyota 2az-fe rods will work on the k24 crank with no modifications and result in a slightly taller CH of 1.004. That and the smaller pin would make that rod ideal if it keeps the pin out of the oil ring land
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Oh I like where this is headed. So now we're saying if we get a custom piston developed then we can use an unmodified connecting rod (but not necessarily the f20c's)?
I'd throw down on a set of custom pistons in the name of science
I'd throw down on a set of custom pistons in the name of science
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From: Raleigh, NC
Originally Posted by deathsled,Sep 10 2009, 08:16 PM
Oh I like where this is headed. So now we're saying if we get a custom piston developed then we can use an unmodified connecting rod (but not necessarily the f20c's)?
I'd throw down on a set of custom pistons in the name of science
I'd throw down on a set of custom pistons in the name of science
the engine will end up with a 1.51 rod/stroke which is MUCH better than using the h22 rod, and a very lightweight piston due to the short compression height.
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From: Huntsville, AL
Any ideas on journal width on the Toyota rods?
Btw, my math says that the compression height with the 2AZ rods would be .988 which would be all up in the oil ring with a 22mm pin, even with a tight ring pack:
2AZ rod is 5.866, H22 is 5.636, difference is .23", H22 compression height is 1.218 according to here:
http://theoldone.com/components/pistons/index.html
1.218-.23= .988
And can anybody get a width on Accord rod journals? If the Accord cranks aren't usable, then we're starting to add up quite a pile of cash for what was supposed to be a super cheap stroker option... Of course, if we can use the Accord cranks, and we can find 2AZ rods for the same price as Belfabs or Eagles for a Honda, then we (you guys, I should say, lol. I certainly haven't done anything at all) are definitely onto something...
Btw, my math says that the compression height with the 2AZ rods would be .988 which would be all up in the oil ring with a 22mm pin, even with a tight ring pack:
2AZ rod is 5.866, H22 is 5.636, difference is .23", H22 compression height is 1.218 according to here:
http://theoldone.com/components/pistons/index.html
1.218-.23= .988
And can anybody get a width on Accord rod journals? If the Accord cranks aren't usable, then we're starting to add up quite a pile of cash for what was supposed to be a super cheap stroker option... Of course, if we can use the Accord cranks, and we can find 2AZ rods for the same price as Belfabs or Eagles for a Honda, then we (you guys, I should say, lol. I certainly haven't done anything at all) are definitely onto something...
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From: Raleigh, NC
the toyota rod is the same width as the k24 0.780"
the h22 piston sits about 0.025 in the hole when used with h22 rods. (that is bad if you ever want to make good power)
I have use some custom pistons that are very short with a narrow pin and a support ring under the oil rings. that was with a 0.948 compression height with a 0.787 pin. (17mm)
I dont have the funds to do this, but if someone is willing i'll do the work to get a "formula" figured out.
the k1 rods retail for about $400 a set, then ~800 for the pistons, the cranks are cheap and easy to come by.. If you did the work yourself the whole thing wouldnt be all that expensive. around $1500 depending on what bearings and gaskets you use.
the h22 piston sits about 0.025 in the hole when used with h22 rods. (that is bad if you ever want to make good power)
I have use some custom pistons that are very short with a narrow pin and a support ring under the oil rings. that was with a 0.948 compression height with a 0.787 pin. (17mm)
I dont have the funds to do this, but if someone is willing i'll do the work to get a "formula" figured out.
the k1 rods retail for about $400 a set, then ~800 for the pistons, the cranks are cheap and easy to come by.. If you did the work yourself the whole thing wouldnt be all that expensive. around $1500 depending on what bearings and gaskets you use.
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A 17mm pin at 9k+rpm hanging on a big ole 87mm piston sounds kinda sketchy. Even with little tiny strutted skirts we're talking a ~325g/ 70g piston/ pin pair... And we're not talking about using a 17mm pin, we're talking about using a 22mm pin on an off the shelf Toyota rod, right? I guess they could be bushed down, but that's a janky solution at best, I think.