Newb needing help in engine selection

[gearheadmb]

Heres the story, I've got a 90 yj with a 258 carbed engine. I've wanted to go injected for quite some time, I had considered using a gm TBI from a 4.3 litre or a 4.0 swap.
After doing some research I'm thinking "what the hell, might as well build a stroker." I've been an auto mechanic for 10 years but this will be my first time doing major engine mods for something computer controlled. I intend to get a 4.0 and get the PCM and harness with it. My question is what years make the best stroker candidates, specifically as far as engine management is concerned? It seems like obd2 is alot better to work with on stock units because they interface better with the scan tool and can give alot more live data, does the obd2 systems react well to the stroker setup? If you stroker gurus were starting one from scratch what would you use?
Thanks
Mike

[sudo chop]

From what I know -limited,- the OBDII is just slightly less adaptable at learning new fuel trim.

Other than that, and obviously the human interface being a bit more convenient, I don't know that there is much difference.

Besides the computer altogether, I'd say that the 98XJ is a good year (and its and XJ and they are often quite cheap if they've been given up on), but I may be a bit biased there since thats what I've got. It has high fuel pressure ~49 psi, which I think is good since from what I know best fuel atomization is at 55psi. It will come with what I think is the most amiable of the heads (0630), the NVH block, a power steering mount that is oddly enough the new style that works with the new intake manifold even though the new manifold didnt come out for another year, and at the same time have the advantage of not having a PCM tuned for a more restrictive head and emissions... Maybe some other things, but as far as the small differences go, at least the ones I know about that is, I feel like those are all tops... Except the OBDII thing, if that can be considered less desirable, which I will soon find out when I try to run mine.

Best to wait for more responses though. We may both learn something.

[Cheromaniac]

At least you already have the 258 crank & rods so that's a start. My advice would be to find a 4.0L long block from a '96-'99 TJ or XJ as the basis for your stroker build. It has the aforementioned 0630 head (good), and the block has the NVH fixes with stiffer main webs and a main cap girdle.
I'd go for the '91-'95 OBD I computer, wiring harness, and sensors rather than OBD II because it's more adaptable to performance mods. I'm running the stock '92 computer on my XJ and driveability is fantastic. Other external parts you'll need are:

1. '96-'99 distributor with cam position sensor.
2. '00+ intake manifold, '91-'95 TB with TPS and IAC.
3. '91-'95 firewall-mounted MAP sensor.
4. '91-'95 injector rail, fuel pressure regulator, and fuel lines.
5. 24lb injectors (Accel or Ford Racing).
6. YJ fuel tank and '91-'95 YJ fuel pump.
7. '91-'95 XJ or YJ alternator.
8. '91-'99 header from XJ, YJ or TJ.

If the '91-'95 parts turn out to be difficult to find in the junkyards, another option would be to buy a totalled '96-'99 TJ and use it as a parts donor.

[Donnie_K]

I can tell you that in 98 alot of the plugs for the sensors changed. They're otherwise the same sensor, yet cost more for some reason. I have a 97 XJ, and a friend of mine has a 98. I was shocked at the price differences on all those sensors...

[sudo chop]

It's funny you said that because just earlier I was looking at all of the sensors from my 98 and from the 99 motor I pulled and a lot of them are different too, so thats odd that 97-98-99 would all be different... Hmm

[Cheromaniac]

Well there you go. If you choose the OBD I system you won't have that problem 'cause the '91-'95 sensors are all the same.