damn, been a while since I posted on here but I figured if anyone knew this stuff, you guys would.

I got a new project that I'm working on, a 93 dx hatch that I'm tossing the drivetrain from a 91 LS into. I already got the engine in and running this past weekend and I pulled the head off to start porting it all.

basically, I got the hasport cable converion and engine mount kit and spliced the LS's OBD-0 harness into the civic's chassis harness. After sorting out all the stupid extra vacuum hoses on the a1 (good god nightmare lol) and getting rid of excess crap, etc it was running pretty damn good.

I have a friend who gave me a set of valves from a B18b1 and a set of cams/adjustable cam gears as well.

I figure while I've got the head off porting it and the intake manifold I might as well have the seats cut for the larger b1 valves if they'll fit the head. Will they physically fit in the a1 head or was the head redesigned or something? also, will the b1 cams be any kind of upgrade as well?? I measured them real quick with a digital mic and it seems they're only about .07" longer per lobe which doesnt seem really like much and could honestly mean nothing if they wont fit as they'll have been redesigned as well which would throw that measurement into the trash bin.

I only ask because after doing some searching on here and abroad I've read that the main difference in the a1 and b1 is the head and intake and the small valves in the a1 head....I can basically null and void this by porting the head (free) and cutting the seats for the valves (free as well from a friend) and have the power from the b1 for basically nothing.

or am I thinking crazy and wasting my time??

 

doh! nobody have anything at all to chime in on with this??

sniffle

 

plus i would use just the cams, from what i hear there are the main difference in the power outputs b18a1 130 hp, b18b1 140

 

The valves are all the same size on B18A1 and B18B1.

90-91 B18A1 had a "small port." I don't think it matters at all, the problem with the stock LS is the camshaft profile - Speedy made 340 whp @ 12 psi @ 6800 rpms with a set of Web-ground Crower billets on a 91 B18A1 small port head. Those are OMG V-TECH Y0 numbers, albeit 500-1000 rpms too low...

If there is any difference in the camshaft profile acros the years, it does not matter, is of no consequence, and is not worth swapping worthless stock bullshit for different worthles stock bullshit. You will not make 1 whp difference.

One look at the ignition maps for 90-91 PR4 ECU, 92-93 PR4/P73, 94 P74, and 95 P75 ECU explains the 130, 140, 142 hp ratings. The difference between B18A1 and B18B1 is in the ECU.

 

The b20b/z cams will make more than 1whp, shall we make a bet? But I do agree not worth the time to swap over or worth the money to spend. Unless they are free I wouldnt buy anything but some nice regrinds or some good billets.

 

Speedy's torque peak with the Web ground billets was at 6200 rpms. Short duration (250 degrees - stock is 230) with very high lift.