B16/B20 swap

[cbcrx87]

I have a 87 crx witha b16 swap and lost #3 cylinder somehow....

and have a chance to get my friends B20 from his prelude
it should drop right in (technically) right

all the info i have found so far points to yes....

i have it narowed down to will the B16 manifold work, or will the wiring plug in with minor changes

[integra96lsvtec]

i say just go for it then u will be getting a little more power and if u do the b20 vtec u are in buisness

[lxndr]

The Prelude B20 is different from the Civic/Integra B-series motors, the motor tilts back in the engine bay and the mounts are different from the Civic/Integra B-series. The head alignment dowels will need to be drilled out in order to accept your B16 head and you need to tap the block for an oil line in order to run your VTEC head.

You're better off picking up another B16 block, a B18A/B (LS block) or a B18C block. The B16 is one of the best Honda motors ever, the rod/stroke ratio is near perfect meaning it's a great motor to modify for more power. Granted nothing beats a larger motor, but the B16 is designed to be a high reving motor which is how smaller motors make power. This is the reason why the B16 came with a VTEC head, so it could take advantage of the higher rev limit of the block.

Besides, most every Prelude owner I've met says the Prelude B-20 is the worst of all the B-series motors.

[lxndr]

Originally Posted by hondacivic99sivtec

hey your b20 would just drop in, and your b16 head could go onto the b20.
i got a thread for you to read, it will explain everything.

http://www.automotiveforums.com/vbul...d.php?t=576945

^^This link is great, I've read it many times, but it's not for a Prelude B20 block.

Most people assume that the Prelude B20 block is the same as a Civic/Integra B-series motor, it's not. It's like how a D16A1 is a D-series, but it shares very few parts with other D-series motors.

Here's a pic of a B20 in a Prelude:

Notice how far the motor tilts back.

[hondacivic99sivtec]

wait ain't a b20 also in a crv? why do you keep compareing it to the b16 and b16?
you know they make a dowel pin kit right?
and you don't need to tap your block. buy an adapter plate from full-race.com

and i got one for ya.
what's the dif. between a crx b20 and a 'lude b20?
and of 'course the mounts ain't the same, however, if he already has b-series mounts it will drop in. duh b20 b16 b18 those are all b-series. i know a guy that had a b16 in his 'teg and went b20/vtec no problem. it drop right in. he even got his motor out of his sister's wrecked 'lude.
so what's the dif. again?
and the b20 isn't a bad engine it's the connecting rod bolts, bearings, etc. in the bottom end that make it bad. who ever spoon fed you that crap needs to go learn something.

[integra96lsvtec]

b20 and b18 have the same exact problem weak bottom ends but as long as u replace it with good parts u will be fine

[Figori]

Now, before you go off on lxndr, let me explain something else. The website you posted is for 4TH GEN CIVICS. They have a little more room in the engine bay, the mounts are in different places, not to mention, their wiring is completely different. Also, the different years of B-series motors did have differences, along with certain years of the 'lude B20's. So, he's right in assuming that it might not work. So, before you bash, try to shoe horn it in and see what happens. -peace

[CivicSpoon]

Originally Posted by hondacivic99sivtec

ok here we go read this and learn, it is really good if you could understand,

http://www.automotiveforums.com/vbul...d.php?t=161203

so i don't wanna be rude but... uh... I TOLD YOU SO!!! so next time please don't try to tell me i'm wrong if i think i'm wrong i will say to correct me.
now go read.

You are being rude, and you are wrong. The B20a from the prelude and the b20 from the crv are 2 completely different engines. lxndr is completely right, the prelude b20a is the bastard of the b-series (not just compared to the crv b20). That 4th gen thread is all about the crv b20, and you should read page 2 of that thread where Kris clearly says: "You cant use the old school b20a from the early preludes." while responding to someone talking about doing a b20/vtec. More proof for you...

12th and last post on page: http://www.honda-acura.net/forums/sh...d.php?t=242562
http://hondaswap.com/engine-building/b20a2-swap-65978/

[cbcrx87]

thats wat i tought just coverin my bases ya know, i read the B20 myths page and thought i would ask about the 1gen crx but i know it leans way back in the engine bay lol, and i knew it was the baster child but i was thinking if it bolts up to the ys1 tranny then i could make it work lol
but i would be better off getting a new B16 or B18c possibly lol
thanx

[cbcrx87]

wats the standard psi for the jdm B16A
should be around 200 right

[lxndr]

Originally Posted by hondacivic99sivtec

so i don't wanna be rude but... uh... I TOLD YOU SO!!! so next time please don't try to tell me i'm wrong if i think i'm wrong i will say to correct me.
now go read.

There is so much hear-say on these forums it's ridiculous. As mentioned, most people think the Prelude B20 is the same as any other B-series when it's not.

Usually people don't know when they're wrong, if you think you're info is wrong why whould you even post it and ask to be corrected? This is why I felt the need to clarify the facts (or lack of) within your post.

Sometimes people take the "I heard that you can ____ " or, "I know a guy that ___" (fill in the blanks) as truth, and keep passing on the same misinformation again and again because so many other people "heard" the same thing. If someone knows someone who performed a unique mod, the person relaying the info may not know all the facts about what really happened then simply tells someone else "yeah, it can be done" but can't supply any technical information. This hear-say accompanied with assumptions is exactly how the cycle of misinformation has grown to absurd levels, then someone who has actually held these parts in their hands gets ridiculed for knowing better. Do people say "I know someone who did blah blah blah", just to make themselves sound credible?

If your buddy swapped a B20 Prelude block with a B16 head into an '84-'87 Civic (which is the forum we're in) or any other year Civic then please make me look like an ass and post some proof, otherwise you just made yourself look like the jackass.

BTW, this info was not "spoon fed" to me, I've researched the possibility of using the Prelude B20 in my car because they are plentiful in my local junk yards. I've physically examined the Prelude B20 block and have done hours of research. I soon realized that the reason these motors are so plentiful in the junk yards is because no one wants them, so I picked up a B18 instead. So let me ask you, are you sure 'you' know the difference between a Prelude B20 and a CRV B20?

And... just to clarify, my argument was not wether or not a B16 head will fit on a B18 or B20 (I know it will, that is exactly what I'm currently building), my argument was that a Prelude B20 just won't work. Look at the picture I posted, can you not see the obvious difference in the Prelude B20 motor from the pic? Just imagine how screwed "cbcrx87" would be if he listened to you and ended up being another casualty of internet hear-say.

[lxndr]

Originally Posted by cbcrx87

wats the standard psi for the jdm B16A
should be around 200 right

I don't know what the exact specs are for a B16, but a healthy stock motor should have somewhere between 170-190 PSI.

The problem may not be your block, it could also be your valves or just a bad head gasket, but I'm betting it's your rings. An indication of bad rings would be blue smoke under hard acceleration, or in really bad cases it will blow smoke all the time.

An easy way to test your rings is to run a compression test, then squirt a little oil into the cylinder and run another compression test. If the second number is significantly higher, you've got bad rings. If this is the case you could look into simply replacing the rings and honing the cylinders rather than replacing the whole block. Personally, I'd suggest rebuilding the whole motor, but you may not have that kind of time and the ring/honing process can be done in a day or two.

[hondacivic99sivtec]

ah... ok, i'm sorry everybody. don't listen to what i posted, i'll just stay out of this one, listen to civicspoon, he's smart.

[integra96lsvtec]

jeez dirty what are u thinking??

[hondacivic99sivtec]

hey! look here ryan! you didn't know either!!! quit talking like cory!!!