what the difference btwn the b18b1 block and b18a1 block...would the a1 accept a hydrolic tranny or the b18b1 head...im going to build it but i find more a1's than b1's so im i need a reply asap..thanx

 

only thing that i think is different is the years b18a is 90-93 ls and b18b is 94-up ls motor.

 

so u think or you know the only thing different is the year....everything else is interchangable?

 

everything is interchangeable, differences are subtle ( some wiring, fan switch is in a different loc. and some other little crap)

but yeah, tranny, head, etc. can be interchanged

 

the bigger diff is the intake mainfold. and the the tranny.. and i think the header is lil small too

 

well in the junk yard and all i can find is a1's and ima build it anyways so i really was just wondering if everything from a b1 fits on the a1

 

the a1 and the b1 are fairly much the same the a1's just older than the b1, a few simple things might be different, but nothing should be too much different.

 

so i can put on a b18b head on with out worrying about tapping any holes or nothing?

 

bolts right in.

 

another quik question...how can i distinguish a b1 head from an a1 head...is there any serial numbers or codes around it

 

you can just look at the year by the exhaust manifold

 

is it near the ports of the head or the actualy stock exhaust manifold

 

I got a b18a1 and its the excat same u can build an a1 the same way u can build a b1 there is no differnce besides obd0 and obd1 so an a1 can make the same whp as a b1

 

the a1 also has the breather box in the back of it that the b1 doesn't, so if your going hi performance with it its a better block to have because of less crank case pressure issues.

 

Yeah but the B1 flows better. 10-12 hp more than the 90-91 a1. The 92-93 a1 wouldn't be to bad to work on, but the b18b1 head is the one I'm looking for to put on my b18a1.

 

my b1 has the black breather box its on all bseries motors

 

X2 im swapping a b1 for an a1 as we speak. the b1 has the breather box. there are a few differences like on the back of the block the b1 has a plug next to the oil pressure senor and the a1 has a sensor which im not sure what it is yet. also there is an extra nipple on the thermostat housing on the a1. other than that and the cams they are exactly the same

 

94-95 b18b's have the breather box. 96+ do not.

 

the b18a has a cable tranny,a breather box,an fitv(fast idle valve) and its 12 hp weaker due to its different style intake and exhaust manifold,its ecu mapping,its cams. the b18a and newer b18b do also have different valve covers aswell

 

i belive the B1 has stronger webbing around the cyls..

and some sensors will be in different locations


b1 = 140hp
a1 = 130hp

 

Yeah we had some trouble because my 2000 b18b1 had a crank sensor and the my older b18b1 block did not. So more work ended up being done then planned.

If you plan on putting an aftermarket ecu on the car then don't worry about this.

 

i have a 2001 grs head. could i put that on a a1?

 

yeah u can but that then becomes ls/vtec and have to tap a few holes and do a little work on head and block so it can be "relaible"

 

let me know how your build went. How much horse did you get out of it

 

how did you get it to work ? I’m running obd1 I believe my b18b1 had crank sensor but my b18a1 doesn’t. I’ve been stuck on this all day