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awa18
09-13-2005, 12:04 AM
hey guys i took out a big end bearing in my 86 accord running a b18a engine im still deciding weither to just fit a new b18a or fit something else does anyone have any sugestions i wouldnt mind a bit of vtec if thats possible?? and how difficult would it be to do

SteveDX89
09-13-2005, 02:29 AM
If you have a B18A in there already, all the other B-series will fit the same using your current mounts. If you want VTEC, you will have to add a subharness from the engine to ECU in order for VTEC to work.

bobafett
09-13-2005, 06:07 AM
yeah read up at www.homemadeturbo.com they have some 1 wire vtec conversion info...

also all you would need for vtec is a b16 (most common) or other vtec head, and obviously rebuilt your b18a. :) its a nice qiuck way to make some dirty power!

thegreatdane
09-13-2005, 07:35 AM
What B18A engine is that? Carbed or fuel injection?

carotman
09-13-2005, 01:53 PM
Thje B18A is carbed

The B18A1 in EFI

awa18
09-13-2005, 04:15 PM
thanks guys so just to make sure im understanding this if i rebuild my b18a block and fit a b16a head will this fit or is it easier to fit a whole b16a engine i got priced $1200 new zealand dollars for a b16a conversion kit

awa18
09-13-2005, 04:21 PM
also my engine is dual carbed how do u convert it to efi to run a b16a

carotman
09-13-2005, 06:46 PM
you can't put a B16A head on a B18A. The B16A head will fit on a B18A1 only which is a totally different engine.

I suggest you just find an engine from a 2.0SI Accord and install it in your Accord. You will have to use the head from the B18A on the B20A if you still want to use the carburetors. If not, you can convert your Accord to EFI or have a custom manifold made.

You could swap an entire B16A engine but you will have to fabricate custom mounts for that.

The easiest swap would be to replace the engine with another B18A. however, having the B20A bottom end will give a nice torque upgrade

awa18
09-13-2005, 11:13 PM
thanks man that sounds like a good idea i can get a compleate b20 engine for $300 thats only done 100,000 ks im guessing it doesnt matter if its out of a prelude or not does it? and when swapping the had over to i use a head gasket for a b18a or the b20a and when u say itll give me more torque will it be much dof from the b18a plus will my tranny bolt straight on

SteveDX89
09-14-2005, 02:34 AM
Sorry, thought you were refering to the other B18. Disregard my post.

thegreatdane
09-14-2005, 07:38 AM
Thje B18A is carbed

The B18A1 in EFI

Excactly my point.



You should be able to use either headgaskets since they are both the same bore size, but if you want to be on the safe side, use the B20A gasket.
It doesnt matter if the engine is out of a Prelude as long as it's an '84-'87 2nd gen prelude. The B20A engine out of an 88-91 Prelude wont work.
I would be very surprised if your existing tranny wouldnt fit the B20A block. It should fit right on. Hard to say how much HP and torque you will gain from it since you're nearly the only one on this board in posession of a B18A engine.

awa18
09-14-2005, 11:36 AM
ok cool thanks for the help i might start that this weekend it should be interesting and when you say not many people have a b18a in their accord is that because they didnt get released into the market for where you guys live?

thegreatdane
09-14-2005, 01:25 PM
Yes the B18A engines were unfortunately only available on the Japanese / asian market.

carotman
09-14-2005, 01:35 PM
thanks man that sounds like a good idea i can get a compleate b20 engine for $300 thats only done 100,000 ks im guessing it doesnt matter if its out of a prelude or not does it? and when swapping the had over to i use a head gasket for a b18a or the b20a and when u say itll give me more torque will it be much dof from the b18a plus will my tranny bolt straight on

The B18A and B20A headgaskets are the same. The timing belt is also the same I beleive. You HAVE to use the B18A head if you want to keep teh carbs because they ahve a different port shape. The transmission should bolt right away to the B20A block. However, I don't know the B18A's gear ratios. Maybe the B20A gears are a little better for performance. At what RPM is the engine running at 100 km/h ? My B20A is a 3k rpm

awa18
09-14-2005, 11:17 PM
yeah thats about the same as my trannie aye its great cos it has quite short ratios right through to third then it starts to widen out and how much better are the b engines over the a ones

carotman
09-15-2005, 06:58 AM
The B engines have a better flowing head and better tuning ability due to their DOHC configuration. The A engines have a cast iron block tough.

awa18
09-21-2005, 10:39 PM
hi guys i have the new engine in and it makes a big difference from the b18a just wondering what can i do 2 it now for performance