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z0ne_3
08-09-2006, 07:06 AM
Ok this is the deal... I have a JDM b20b out of a 98 Honda Orthia with 9.2:1 compression... Im planning on doing a b16 or b18 head swap. I was told when u add a v-tec head it add somewhere around 1 compression. Here is were im lost. I was told and after all my reading on this site and others. U need to change you pistons one rods to run v-tec on a b20b. If i change my pistons what type will i need not to run too much compression with v-tec...???
BTEC
08-09-2006, 07:19 AM
CORRECT ME IF IM WRONG BU U WANT TO KNOW IF U PUT A B16 OR GSR HEAD ON UR B20 BLOCK WILL U HAVE TO CHANGE UR RODS AND PISTONS AND IF SO WHAT RODS AND PISTONS SHOULD U USE. AM I CLOSE?
Seymour222
08-09-2006, 11:33 AM
Lets put on our thinking caps.
§treet_§peed
08-09-2006, 12:51 PM
Ummmmmmm.:english:
z0ne_3
08-10-2006, 01:44 AM
CORRECT ME IF IM WRONG BU U WANT TO KNOW IF U PUT A B16 OR GSR HEAD ON UR B20 BLOCK WILL U HAVE TO CHANGE UR RODS AND PISTONS AND IF SO WHAT RODS AND PISTONS SHOULD U USE. AM I CLOSE?

I wanna know what type are worth buying. I know u have to change the pistons and rods. But i dont want to much compression....
2.0civic
08-10-2006, 02:47 AM
whoever told you that you HAVE to change them is full of shit
z0ne_3
08-10-2006, 07:15 AM
whoever told you that you HAVE to change them is full of shit

Well my b20b readlines at 7000 so what they where telling me if i wanna run higher RPM i need to change the pistons and the rods to handle it...
BTEC
08-10-2006, 07:23 AM
whoever told you that you HAVE to change them is full of shit
if they said u HAVE to then they are full of shit but id reccomend it if ur gonna beat the car
cons about b20 vtec is with the lift of vtec cams and non vtec pistons (very little if any valve reliefs) increases ur chances of valve to piston contact bc of how far the valve is pushed into the head when ur in vtec.

as for the rods the rod bolts stretch. It is popular to put ARP rod bolts in but alot of na guys (mike jawns) reccomend swapping out rods completely if u want to rev past 8200 i think.

lastly, supposedly revving the hell out of the b20 block will cause the sleeves to crack bc the bore is 84mm and the sleeves are so thin.
Hondatwin23
08-10-2006, 08:11 AM
wow, that is just straight bad information
you dont need to change the rods and pistons but for most people that beat the hell out of their car it would be a good idea, not because its a b20 or any other application. secondly if your going to change the rod bolts and its a stock rod why just save more and change the rod also.

i had a b20 with a port and polished gsr head and stock block, no problems until u hit 9700 rpms and up. JUN ecu is the shit !
BTEC
08-10-2006, 08:21 AM
..you dont need to change the rods and pistons but for most people that beat the hell out of their car it would be a good idea, not because its a b20 or any other application. secondly if your going to change the rod bolts and its a stock rod why just save more and change the rod also...
U PRETTY MUCH SAID THE SAME THING I DID ABOUT THE RODS AND PISTONS. I DIDNT SAY U HAVE TO BUT IF U WANT TO REV IT HIGH THEN U SHOULD BC OF THE HIGHER VALVE LIFT, THE ROD BOLTS STRECT AND HE RODS IN GENERAL ARE OF COURSE WEAKER THAN FORGED RODS.

HOW IS BUYING A SET OF RODS SAVING MONET OVER BUYING A SET OF ROD BOLTS? $80 FOR ROD BOLTS VERSUS $300 FOR A SET OF RODS AINT SAVING MONEY.

I WOULD HAVE TO SEE U REV A B20 VTEC TO 9700 BC I SERIOUSLY DOUBT THAT. ECU POBABLY ALLOWED IT BUT VALVE TRAIN AND BOTTOM END AINT GONNA HOLD.
z0ne_3
08-10-2006, 07:16 PM
Well aint no way n hell imma rev my shit past 9.5 anyway. Shit i dont wanna rev it past 8 I make good power with this motor down low. But the cam that with on came with are gay. And if i buy soem stage 2 or 3 cams and the kit u need to handle them. I might as well spend a lil more and go v-tec. Thanks for the info guys im hearing so many different things im losing my mind... I just wanna rev to 8 maybe a lil higher i dont even wanna touch 9...
umfogotmyname2111
08-11-2006, 12:35 AM
whoever told you that you HAVE to change them is full of shit

have to agree with that man...my brother has a b20 vtec with the b16 head in his DA and never changed the pistons or rods and runs great....takes it to 8000k+ all the time when racing and has never had a problem with it so it can definately take it....as for the 9000+ i wouldn't recommend it unless you don't like the motor or have done work to it so it can take it....his car is acutally the one in the car pics area that says pics of my da...
Hondatwin23
08-12-2006, 07:10 PM
U PRETTY MUCH SAID THE SAME THING I DID ABOUT THE RODS AND PISTONS. I DIDNT SAY U HAVE TO BUT IF U WANT TO REV IT HIGH THEN U SHOULD BC OF THE HIGHER VALVE LIFT, THE ROD BOLTS STRECT AND HE RODS IN GENERAL ARE OF COURSE WEAKER THAN FORGED RODS.

HOW IS BUYING A SET OF RODS SAVING MONET OVER BUYING A SET OF ROD BOLTS? $80 FOR ROD BOLTS VERSUS $300 FOR A SET OF RODS AINT SAVING MONEY.

I WOULD HAVE TO SEE U REV A B20 VTEC TO 9700 BC I SERIOUSLY DOUBT THAT. ECU POBABLY ALLOWED IT BUT VALVE TRAIN AND BOTTOM END AINT GONNA HOLD.

1) I said save more money and do the rods also.
2) I do not need to show you anything because i know what ive done and that is that.

p.s. look at the spec on a jun ecu and ask a person what else was done to their car before u go typing. lastly turn off ur caps.

peace
Georgia_boy
08-15-2006, 04:47 AM
if they said u HAVE to then they are full of shit but id reccomend it if ur gonna beat the car
cons about b20 vtec is with the lift of vtec cams and non vtec pistons (very little if any valve reliefs) increases ur chances of valve to piston contact bc of how far the valve is pushed into the head when ur in vtec.

As for the rods the rod bolts stretch. It is popular to put ARP rod bolts in but alot of na guys (mike jawns) reccomend swapping out rods completely if u want to rev past 8200 i think.

lastly, supposedly revving the hell out of the b20 block will cause the sleeves to crack bc the bore is 84mm and the sleeves are so thin..I'd listen to the man, he seems to have done his research on the b20. :goodjob:

HOW IS BUYING A SET OF RODS SAVING MONET OVER BUYING A SET OF ROD BOLTS? $80 FOR ROD BOLTS VERSUS $300 FOR A SET OF RODS AINT SAVING MONEY. :werd: :screwy:
ash7
08-15-2006, 06:03 PM
Ok this is the deal... I have a JDM b20b out of a 98 Honda Orthia with 9.2:1 compression... Im planning on doing a b16 or b18 head swap. I was told when u add a v-tec head it add somewhere around 1 compression. Here is were im lost. I was told and after all my reading on this site and others. U need to change you pistons one rods to run v-tec on a b20b. If i change my pistons what type will i need not to run too much compression with v-tec...???

1) What sites have you been reading off of? - don't read them anymore
2) How much compression do you consider "too much?" - anything below 12.5 is good to go.

Use the compression calculator on cspeedracing.com to figure out your numbers, if it adds up to over 13:1 then you need to rethink your piston choice, or run a Cam2 mix.