ok so im building an all motor b20/vtec application, i have a ported and polished b16a2 head, milled 20 thousandths, 3 angle valve job, REV dual valve spring and titanium retainers, S2 S2 cams, S2 pro IM and S2 70mmTB, RC 440 injectors, with AEM Fuel rail and Regulator, but im still on the fence about the bottom end(already have the needed things o do swap correctly like the rod bolts oil pump girdle etc.... )it needs to be bored out so its the same price to bored it out to 84.5mm to 85mm but im scared of cracking the stock sleeves from them being too thin, i am planning on using wiesco 11.7 to 1 HC pistons and Eagle Rods or shot peen rods (not sure if the shot peen rods will handle this) but final goal is to do 230+ HP and then use a 50/75 shot of nitrous.

so do u think the rods will hold up to the abuse and should i just bored it to 84.5mm or 85mm? pistons and boring it out are all the same price for the extra little displacement.

 

There is no point in taking a stock sleeved b20 block passed 84.5mm
You won't gain much power by going 1mm larger etc.
A girdle isn't going to be necessary unless your road racing the motor.

 

the b20 block has already been fitted with the girldle, it lost compression and i took it apart and noticed a huge scratch on the number 3 cylinder wall, so machine shop says new pistons/rings (had stock b20b pistons) and a bore and ill be good to go again so why not leave it on if its already there,

 

Are you referring to a block guard or girdle ?

 

shot peened rods will be fine for your application. if you want to make the rotating assembly lighter you could always go forged, but thats over kill imo. sounds like a good build thus far. listen to mr. vega and dont go past 84.5mm. your sleeves will be fine if you stay within reasonable bore. its not a boosted motor so the cylinder pressures shouldnt be high enough to crack the sleeves.

 

SO..MUCH..KNOWLEDGE... lol

 

not much power gain but alil more torque gain , Golden Eagle Block Guard, 84.5mm RS Machine piston and Shot peened rods with arp rod bolts, <- My old b20 set up i loved it

you should make good #'s with your head and this block combo, and a really good tune

 

yea the block already has a GSR girdle installed in it, i was worried if the shot peened rods and sleeves would hold up to this build and a 50/75 shot, trying to hit close to 300hp so depending on all motor numbers depends on nitrous shot( have a direct port kit)

 

run a streetsweeper header

 

dont waste the money on shot peening anything it will not help,use the money for forged rods and pistons if your going to use N20