i've been reading up on the thred about the 62mm type-r throttle body, and it seem like a pretty simple mod, i know all this stuff has been cover in many threads before but the search engine on this fourm sucks and i cant seem to find the right answers...
also im goin to replace evey single gasket and seal on the motor, i do have some hook-ups for felpro products or would you guys/gals suggest i go staright to honda.
im to assume all the parts for the JDM B20A and the USDM B20A5 share identical part numbers besides the pistons and rings and cams right?
is there any other suggestions that you guys/gals might have to improve my progress.
thanks in advance, i hope you can help me out and i will do my best to share my knoweldge with you guys too
Yep you can use B16 pistons but WHICH ONES? There are many different variations of B16 pistons. If you use stock pr3 pistons then your not gaining much.
I would recommend to use ITR or CTR pistons but i dont think just anyone should use them unless they really know what they're doing and fully understand about using those pistons. Basically, if you have to ask about them, then you shouldnt be using them. Theres more work involved then just dropping in new pistons.
A better mod for you would be to port match and polish the manifolds. More of feasible thing for you to do and not as complicated. And you will probably only need a 60mm throttle body with what you have planned. A 62mm on that would be overkill. Just get the Vigor TB and bore that out.
And im sorry if i sound like an asshole but im just telling you the truth.
The only issue I have seen any one post about with the b16 pistons is the wrist pin hole on the piston is 1mm to small. You can take them to a shop to hone the hole to accept the wrist pin for the b20 rods.
Soviet, what other work are you reffering to?
Also, instead of buying a Vigor TB and boring it you can send your stock tb off to http://maxbore.com/
Quick turnaround and quality work. He can also port match the plenum if you send it in. Which ever TB you go with I would send it to him if your boring it and have it port match to the plenum.
thanks for the advise soviet, i was under the impresion that inorder to use the B16 pistons all that needed to be done was to have the wrist pin holes bored out 1mm in order for the pins to fit.
where can i find those pistons? i live in canda and no one seems to have that kinda shit around here.
and what exactlly do you mean by port matching my manifolds? enlarging the inlet holes on the head and manifolds? what would the advantage of getting a TB of a viggor and boring it out as apposed to boring out the one on the B20?
Soviet...you're kind of on crack bro. USDM B16 pistons are a 6cc dome. That would bring a B20A5 up from 9:1 to 10.98:1 compression which is a pretty huge leap.
tripleblack - the advantage of using a Vigor TB is that it bolts to our manifolds but is physically larger so you can bore it out more without making the walls too thin.
Port-matching the plenum means making the plenum opening (where the TB bolts to) perfectly match the throttle size.
*EDIT*
CTR pistons would bump him up to 11.5:1, USDM ITR pistons would net 10.5:1, JDM ITR would be 10.97:1
All you need to do is have their piston pin hole bored out to match B20A pin size. They will drop right in at that point.
ok so what your saying Kalm Traveler is get a set of B16 pistons and rings take them to my machine shop along with one of my B20 pistons and get them to bore out the wrist pin holes. Can i use my stock wrist pins and rods?
which B16 pistons would you recomend, i would rather not have to run 94 octane all the time but if i were to go with the JDM IRT i could probably get away with 91. correct? second question where can i get these pistons from?
i guess ill be searching the scrap yards or a TB from a viggor what year and engine?
Yea just take your old pistons/rods to the shop with the B16 pistons. They'll be able to get'r done. You can use your stock pins and rods yes... though if you could scrounge up a set of H23 rods you're less likely to snap them and they're a direct bolt-on.
if I were you I'd get whichever you can find for cheapest. the USDM B16A pistons will probably be that, but the USDM ITR pistons would be fine as well (probably don't want higher than 11:1 compression).
I bought a set of brand new USDM ITR pistons on eBay a while back for like $65 +shipping or thereabouts. Also bought a set of GSR pistons/rods for pretty cheap too.
the Acura Vigor was only out for 2-3 years in the early 90's... something like 92-95. It's successor was the 2.5TL but I'm not sure if they have the same intake manifold and TB.
i found a set of nippon racing JDM CTR pistons on e-bay for $160 plus shipping. they are completly stock size just reenforced. but that would bring my compression up to 11.5:1 correct? that is definitaly to high. i cant seem to find any ITR pistons on there if i could be at 11:1 that would be perfect.
I have a buddy that has a set of H23 rods sitting around he said i could have them for $20 so im set for those. just the pistons
H23 rods are definitaly the way to go, espically if im goin with a higher compresion ratio. im just afarid that im goin to have to be running at leat 94octane in order not to ping. but i guess ill just have to find out.
Alright i can tell you that the H23 rods and B16 pistons are not going to just drop in. You need to machine the pistons wrist pin and take out a little of the inside of the piston as well. I know cause ive actually done it. I have CTR pistons in .20 overbore and H23 rods do not just bolt up to those. Need to have the rods and the pistons to get them machined properly. And if you use CTR pistons you need to clay the motor to make sure you dont smack the valves. Thats a nice bump on those. I had all this done and in the end i should have just gotten the custom made pistons.
Stock B16a pistons are a flat topped piston. Honestly if your going to go through all the trouble of putting B16 pistons in you might as well go for higher compression. I wasnt satisfied with ITR pistons so i got CTR pistons and had them a little bigger than the stock 81mm bore. My setup was also a little different in the head i was using so it brought my compression up to like 12.5:1.
i am bidding on a set of Nippon racing pistons on e-bay as we speek they are JDM CTR forged domed pistons so that should bring my compression ration up to 11.5:1 plenty for what i need. along with the H23 rods have them machines to fit the B16B wrist pins and i think i should be all ready to break some valve springs lol.
Well the pistons need to be machined in 2 different places. The H23 rods are thicker so you need to cut into the pistons underside to get it to fit. Just take your rods and pistons to your machinist and he should be able to get it to work if he knows his shit.
And you should have contacted me first before you bought your pistons. I am going to get rid of mine. And they are already machined. Oh well. Good luck with your build.
You will need to get your engine tuned now btw.
the problem id see with using a Vigor TB is that itd have to be sitting upside down on out engines since it mounts on the opposite of the engine from where ours is.
that and its from a Vigor, so the quality of it is gonna be shit.
nevermind, i thought you were talking about the whole manifold, not just the TB. its too early for me to e thinking clearly.
although its probably still crap. i hate my vigor, it doesnt like to work properly even after $2000 of servicing. im a firm believer that anything that touches the G25A1 instantly turns to shit.
i dont think i understand the pistons though, i thought the diamater of the piston was reflected on by the displacement of the engine (ie 1.6L has smaller pistons than a 2.0L). am i totally off on that?
ahh i see what you mean now, well im goin to pick up a TB for a Viggor this weekend from teh scrap yard and see what kinda magic i can work with it. if it doesnt work it doesnt work...
The displacment of a motor is reflected not only on the bore of a cylinder, which in our case is 81mm in a b20 and also in a b16. but the stroke (the distance between the top of the piston at BDC and the top of cyliner mutiply those to measurments and you have your displacement. multiply that number times the number of cyliners and you have to total displacement.
after i posted my input on the B18 bore i had an after thought and realized that i brain farted while i wrote that down lol.
So are the JDM CTR pistons (the ones i found on e-bay in the link on my last post) the have a 6cc dome obviously and that will give me a compression ratio of approximatly 11.5:1.
I will get a set of H23 rods and have the wrist pin holes overbord on the CTR pistons 1mm in order to fit it.
CTR are like 8cc dome or something... they will give you approx 11.5:1 compression, yes.
Will be a pretty mean motor once you get it all together :-D thing is you won't get the most out of it unless you can get it tuned to take advantage of the higher comp and different cams.
as i said im still workin on getting together all the parts and such, but as for cams i plan on getting a B18B1 intake cam moded and then a B21A1 exhaust cam some adjustable cams gears and i think i should be set.
do you think the stock valves/springs/retainers will hold up?
Thats not going to work for those pistons. You need aftermarket cam regrinds. Stock valve train should hold up fine but depends on how bad you beat on your motor. As long as the engine is healthy then you should be fine. Talk to Webcamshafts. I had their #13 grind. Id recommend getting the #13 grind and then telling them to give you .418 lift instead of .415. Cant go wrong with those cams. The Vigor TB will work fine. That white guy just had a bad experience with a Vigor. You shouldnt have any problems with it.
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