ESP.net

I was doing some pondering...

My old H23V Blue Top Rods and Pistons compared to JDM H22 and Rods





Blue Top PDE rod and piston on left and JDM H22 P13Z rod and piston on right


The pictures are decieving, however I did a few measurements... the pistons from wrist pin to the top of the piston outter edge are the same... hmmm... strange... a Normal H23A1 Rod Length would have this piston sticking out of the hole 20k if it's the same as a H22 piston...

So could it be that the Blue Top Rod is actually shorter then a typical H23A1 rod? So Honda could have the piston inside the cylinder obviously?????

Also kind of makes sense from appearance if the H23V Blue Top Rod was a little shorter then the H23A1... because look at the Skirt of the H23V Piston just the skirt on the side is shorter the middle is the same...... could this be for clearance needed do to shorter rod for crank ?????

If so that kind of opens the world of possibilitys of running a Type S piston or Mahle in this setup to boost up the compression ratio with the stock Rods and not having to worry about the piston being out of the cylinder....

If anyone has the H23AV Blue Top Rods off of the pistons do some measurements and hit me up...

ESP.net

------------------------ Update ---------------------------------

From talking to Rosko also who has the H23A Vtec Blue Top apart he agreed the Blue Top rods are about 20k/.020 shorter then a typical H23A1 rod... which is kinda neat.

A USDM/JDM H22A/Type S piston will be able to sit exactly level .0 in the cylinder which would give a decent/stock piston to valve clearance without needing a thicker then OEM head gasket or doing work to the combusition champer or piston. It also allows you to be able to run a more agressive higher lift cam with the 95mm H23AV/H23/F22 Stroke. However rod stroke ratio has to be taken into consideration

Compression ratios would be like the following with OEM headgasket

10.5-1 with USDM H22A pistons which is obviously the same piston compression ratio that is already in it.

11-1 with JDM H22A Pistons.

11.5-1 with Type S pistons



It does appear that the Blue Top Rod length is the same as the F23 141mm, However the rod journal diameter are different from each rod.

ESP.net

H23A Vtec Blue Top and JDM H22A ROD BOLTS share the same thread and diameter of bolt. H22 nut fits on Blue Top bolt. However the Blue Top is not a pressed in Rod Bolt it is a theaded bolt with a 12 point 10mm head, the bolt it self is 9mm just like the H22/H23A1 OEM Rod Bolts. The length of the Blue Top rod bolt is 1 15/16" from bottom of head washer and the JDM H22 is 2". ARP GSR 9mm Rod Bolts are 2 1/8" if I remember right from installing them in a H22 a while ago.

However the Blue Top Rod Bolt is not a pressed in, it threads into the top part of the Rod. So I think there would be no way possible or benefit to installing aftermarket rod bolts on this rod for it being threaded into top of the rod. Unlike the H22/H23A1 which uses a pressed in bolt and a nut.

gaby_315

Do you have pics of tue blue top with mahle pistons