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View Full Version : Look! Jdm B20a V-tec setup!


bullard123
12-29-2006, 06:39 PM
http://www.imagestation.com/picture/sraid146/p387bf3d07aeecc937687618b6d0776b6/f643b961.jpg
http://www.imagestation.com/picture/sraid59/p03d3581143c072adf5fa415c2221aa11/fc5df1f7.jpg
http://www.imagestation.com/picture/sraid146/p5d91fb2ff4ecc9d5c1a79c8955935de2/f643b95f.jpg
http://www.imagestation.com/picture/sraid146/p3b616ebcc5092e3b89fff6d5b9105144/f643b96e.jpg
shepherd79
12-29-2006, 06:56 PM
oh dude, the engine is tilted backwards.
our B20A engines tilt forward, it is a wrong engine.
bullard123
12-29-2006, 07:06 PM
Is it the b20a5? That setup will be nice for our b20a's too
shepherd79
12-29-2006, 07:59 PM
are you sure it is B20? it could CRV B20 with Vtec head on it.
bullard123
12-29-2006, 09:01 PM
are you sure it is B20? it could CRV B20 with Vtec head on it.
Yeah its a b20. its from a guy on prelude power.com here is a quote from a thread I was reading regarding the engine:

it's a ctr head with a dpr port and polish. It needs a new valve seat and valve. The conversion is very similar to a b20b conversion, but you will need a custom headgasket, b16 pistons, and aftermarket rods if you want to rev it at all. The redline is currently 10,500, I can go higher but the tranny wont keep up. It grinds as is. I probably won't ever dyno it because I have a 3rd gen rx-7 and I don't really care what the prelude puts down. If I had to guess I would say 300whp, but I have a ton of mods and custom parts to get that hp number.
2ndGenGuy
12-30-2006, 12:37 AM
I'm pretty sure that's not the JDM Accord B20A. It's more likely what shepherd79 said. They get the CRV B20 engine, and bolt a VTEC head on it. It's called the CRVTEC swap. It's not the same B-series.
SteveDX89
12-30-2006, 05:15 AM
CRV B20s don't lean back. They're straight.
ZackieDarko
12-30-2006, 08:15 AM
i didn't know you could put a vtec head on a lude b20
carotman
12-30-2006, 09:14 AM
Why all the confusion again?

I thought the FAQ/Engine Swaps section was clear enough to identify this engine at a glance? bullard is right, this is a B20A and hell it might even be JDM.

Anyway, this is a 2nd gen B20A. That's what I like to call them now, this removes any confusion. The owner installed a later B Vtec head on it. This is far from a bolt-on Mod. The ones that have done it said that the power gain was a bit disappointing for the effort put into it.

The problem is that they missed the whole purpose of Vtec heads: The ability ot have 2 cam profiles on the same engine. These B20A (1st and 2nd gen) need a different Vtec cam profile in order to work well. Vtec i the best of both worlds. Good low rev cam + high rev cam.

You only have to make the cam profile the B20As need and this will onpletely rip everything appart.
bullard123
12-30-2006, 09:35 AM
Yeah I thought he said it was a B20a. It must be from the second gen lude then. This guy has a spare head he is selling for this setup on preludepower too.
carotman
12-30-2006, 09:47 AM
Yeah it's from a Lude. Still a B20A :p All the internals are the same as our 1st gen B20A. (roughly)
bullard123
12-30-2006, 11:31 AM
Hey Carotman what did you do for the downpipe that connects to the B20a headers? Well im using the ones from the b20a5 engine. Could I just cut the piece off from the downpipe that connects with the headers and just weld it on to my exhaust?
carotman
12-30-2006, 11:33 AM
You're talking about the actual OEM exhaust manifold?
bullard123
12-30-2006, 11:36 AM
You're talking about the actual OEM exhaust manifold?
Yeah the part on the bottom of the headers
http://img265.imageshack.us/img265/759/headerredone3hz6.jpg
carotman
12-30-2006, 11:50 AM
That's a good thing you're using the B20A5 one since you will be able to use the PK2 ECU dual O2 sensor thing :p

I have a B20A5 DC header on my car. Just buy a B20A5 downpipe and modify the angle. It should bolt to the cat converter
bullard123
12-30-2006, 12:11 PM
That's a good thing you're using the B20A5 one since you will be able to use the PK2 ECU dual O2 sensor thing :p
I have a B20A5 DC header on my car. Just buy a B20A5 downpipe and modify the angle. It should bolt to the cat converter
But can I keep my stock exhaust cause I want to keep my dual exhaust set up. So that means I will have to cut the cat converter downpipe off of the prelude exhaust and weld it onto my stock exhaust after I bolt it up of course (well the exhaust I have on my Honda now) right? Sorry if I'm confusing you.
carotman
12-30-2006, 02:39 PM
Well, I don't know if this is what you meant but all you have to do is bolt the B20A5 downpipe to your existing exhaust, cut it after the flexpipe and bolt it to the header. You then need to modify the angle and maybe modify the length.

I'll try to find some pictures of my downpipe and show it to you.
bullard123
12-30-2006, 03:46 PM
Well, I don't know if this is what you meant but all you have to do is bolt the B20A5 downpipe to your existing exhaust, cut it after the flexpipe and bolt it to the header. You then need to modify the angle and maybe modify the length.
I'll try to find some pictures of my downpipe and show it to you.

Yeah that sounds like what I need to do. The pics will be good too. Thanks
thegreatdane
12-31-2006, 07:42 AM
I probably won't ever dyno it because I have a 3rd gen rx-7 and I don't really care what the prelude puts down. If I had to guess I would say 300whp, but I have a ton of mods and custom parts to get that hp number.


looool 300whp, that's never going to happen ever, unless he's turbo'ing it. And 10.500rpm on a 3rd gen lude B20A??? That is just plain stupid.
reanimator420
12-31-2006, 09:22 AM
that calling for trouble at those rpms...................
MessyHonda
12-31-2006, 09:25 AM
lol...10.5k that is like F1 status....it would suck up more gas than you can put in the tank....i still think that it would be a nice project but dont get over your head bullard...the b20 is rare and dont mess with it cuz you cant go to the junkyard and pick one up...unless the b20a5 works.
shepherd79
12-31-2006, 10:08 AM
lol...10.5k that is like F1 status....it would suck up more gas than you can put in the tank....i still think that it would be a nice project but dont get over your head bullard...the b20 is rare and dont mess with it cuz you cant go to the junkyard and pick one up...unless the b20a5 works.

it is not even touching F1 status. F1 engines rev past 19000 RPM.
http://www.hondaracingf1.com/en/index.php?section=25
MessyHonda
12-31-2006, 10:14 AM
yeah i saw a ferrari dyno and i peaked at like 17.5k
Legend_master
12-31-2006, 10:54 AM
10.5K is not much for the newer B-series engines. I know of plenty that rev to 12K and produce power through the whole band. If you build a motor right you can do almost anything with it. As for the motor pictured, just looks like they put a b-series head on a prelude motor. Thats why it leans back
MessyHonda
12-31-2006, 11:06 AM
10.5K is not much for the newer B-series engines. I know of plenty that rev to 12K and produce power through the whole band. If you build a motor right you can do almost anything with it. As for the motor pictured, just looks like they put a b-series head on a prelude motor. Thats why it leans back


yeah i know race cars do that...but an head swap wont get you that..unless you build all the internals to specs....with money anything is possible maing
Cheeseburger
12-31-2006, 11:26 AM
10.5K is not much for the newer B-series engines. I know of plenty that rev to 12K and produce power through the whole band. If you build a motor right you can do almost anything with it. As for the motor pictured, just looks like they put a b-series head on a prelude motor. Thats why it leans back


very true!
thegreatdane
12-31-2006, 04:57 PM
problem is, this is not a newer B series engine. That engine is getting extremely high piston speeds. The oil will not withstand that.
Legend_master
12-31-2006, 05:02 PM
problem is, this is not a newer B series engine. That engine is getting extremely high piston speeds. The oil will not withstand that.


I would have to say that with a proper balance on the internals of the block and a built head, you could rev to 9K. The only thing is that I dont think there will be much power in the upper power band due to the bore/stroke, unless you turboed it, but that is just a whole nother set of problems with the B20a's.
bullard123
12-31-2006, 05:06 PM
Oh one thing I forgot he has a 5 shot of nos too
thegreatdane
01-02-2007, 03:16 AM
I would have to say that with a proper balance on the internals of the block and a built head, you could rev to 9K. The only thing is that I dont think there will be much power in the upper power band due to the bore/stroke, unless you turboed it, but that is just a whole nother set of problems with the B20a's.

At 9K the average piston speed is 28.5 meter per second. Years ago the very highest recommendable was 21-23 m/s, today it's in the 26-27 m/s area.
high piston speeds will create a lot of wear very fast. I personally wouldnt recommend higher than 7.5-8K on a B20A.