advice on b20 integra swap

BLACKnWHITEls

New Member
i have a 1995 acura integra ls with a b18b1. i just bought a parts car for a motor swap and i thought it had the same motor. turns out the block is stamped b20b. i dont know the year of the block yet. i know its not the newer high compression crv motor, cause the weird square intake is not on top of this ones intake. i have no clue if my factory motor, ecu, wireing harness, head is obd 1 or 2. nor do i know alot about this block like the head if its a p75 or not. i know it will bolt up. all thats the same. im wondering if i will need new distriitor, intake, ecu or what. i dont even know if my b18 transmission will fit into the b20 and work right. please help me learn more about what im working with. imma newbie lol.
 

96LSteg

Jemel
If you block is stamped b20b then that's a jdm b20. If it is stamped b20b# (# being another number) then its a usdm (american) b20. Idk if the ecu's will be the same for usdm and jdm. i know usdm b20s use p75s like the LS. I know the jdm head is stamped p8r or something like that. Your LS trans will bolt up. All b series trans will bolt up to any b series. The b20 is just a bored out LS. As for the wiring harnes, that will be determined by a lot of factors like what obd head sensors and dizzy you decide. If you decide to go with the p75 stuff (like the usdm b20) you can just take your head off your b18b1 block and use your harness and ecu and all that good jazz. Your teg is a 95 so that makes it obd1. Obd2 is 96+. Hope that answered your question
 
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96LSteg

Jemel
There a very few differences between the b20 and the b18b1. B20 has a 84mm bore where as the b18b1 has an 81mm bore. The stroke is the same (89mm). Only otherwise difference I can think of is that the jdm b20 has a p8r head which is the best flowing head for non VTEC but it has an 84mm combustion chamber. I believe usdm b20s come with p75 heads which are the same as the head that is on your b18b1. This head flows good but not as good as the p8r head. Usdm B18b1/A1 and usdm b20s should all run on a usdm p75 ecu. However if its a jdm motor you will need a jdm ecu.
 

96LSteg

Jemel
My advice would be to use google like I did a long time ago and learn as much as you can about these motors. It would also be very beneficial if you joined nonvtec dot com like I did because EVERYONE there has either a b18b1/a1 or a b20 so you can learn a sh** ton there as well.
 


BLACKnWHITEls

New Member
hey i appriciate the help man. i think you answered the question. im sure its a jdm block. pretty sure its the p8r head, which means i will need the corrisponding ecu that matches that head.

the parts car that i pulled the b20 out of was also an ls, and the car bucked with you only when the motor was under load. let off throttle, or push clutch in, and the bucking would stop, so i know it wasnt suspension, and i think the ecu being different would cause that. what do you think?
 

96LSteg

Jemel
That could be caused by many different things. It could possibly be from the incorrect ecu as the jdm motors require different fuel amounts than the usdm motors i believe. To be sure you have a jdm head look for the stamp right above the exhaust manifold. It will tell you the year also.
 

BLACKnWHITEls

New Member
if it were the different p8r head, what kind of ecu would i look to buy and install? also do you know if id need a new wireing harness?
 


96LSteg

Jemel
You could look on phearable dot net for an ecu. They will chip them for you too if you want. They run like $150. As far as the harness, if you decide to stay obd1 (which I recommend because that is what you will have to convert to to tune) then u can just reuse the harness that you have and save the headache. Also with obd1 you don't have to worry about a secondary o2 sensor where as obd2 has a secondary in the catalytic converter.
 

96LSteg

Jemel
From what I've read you can use a p75 ecu on a jdm b20 so your LS ecu should be good to go bro.
 

BLACKnWHITEls

New Member
awesome man thanks alot. seriously. im excited man. ive got both blocks sitting on the ground at my house, and ive been waiting for a damn clutch alignment tool to be able to bul my aftermarket flywheel clutch and pressureplate to be able to put it on the b20. so i think im atually gonna get the motor in the car this weekend. hopefully i dont run into any issues. or ill be back on here monday to get more advise. but thanks for tha website. i hecked it out. seems nice. for a rich man that is. lol- naw it wasnt bad for what your getting.
 

jh97gs

New Member
I'm also wanting to do 99jdmb20 swap in my 97 Gs in trying to learn as much as possible before I have a motor shipped to me. So fare I've read I only have to change crank crank sensor in maybe use a adjustable for in also have heard that I don't have to the crank sensor so I'm not sure what I've gotta do?
 

96LSteg

Jemel
I believe jdm motors don't have crank sensors so when you get a tune you can disable it. You also don't need a fuel pressure reg. our fuel rails are good for like 350+ HP.
 

jh97gs

New Member
So won't run without tune? Or can I put my ls sensor on it? I just wanna do basic swap to keep a reliable car. I plan on ordering from hmotors because I can't seem to come up with a good place near me with a good rep. In was thinking b20 just because a little more trq. I see they also have b20z usdm but thought maybe jdm would be less miles on it.
 
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