4.3L XJ Buildup

I used to have an 86 XJ with a low milage 2.8L and 5 speed tranny that I was happy with. It got good milage and I didn't have any trouble with it. Then it developed an idling problem, so I just turned up the idle a little. Then I moved to CA. The smog police got after me and I tried to get carb parts to fix it. I guess it can't be done for that year anymore. The state kindly offered to crush it for me, but I just couldn't crush a perfectly good vehicle. So I decided to upgrade a little with a 4.3L Chevy and a jeep T5 tranny. Lots of stock parts and should have been fairly easy to install. The smog police got involved again and said I needed an auto from an 93 to put behind it. On and on it went. So here is how it goes:





No Chevy is complete without a set of headers and a great exhaust system. A set of smog legal JBA headers, slightly modified, a true 2 1/4 header pipe with true radius mandrel bends into a formed Y pipe and 3" high flow cat. We want it breathing properly.

Also shown is the Advance Adapters flange and shaft for the transfer case.

Next, I got the bright Idea I wanted a 4 speed Atlas behind it. So here it is. The cat approved of course.



Here it is clocked on the engine.





Almost ready to go in. The tranny has been rebuilt with kevlar bands and racing clutches and will be running Red Line high temp synthetic oil.

Why in the hell would the smog nazis care what tranny your running as long as the engine still meets their standards?

If I recall my Chevy stats, the 4.3L is a 90 deg V6. It does not have the same bell housing bolt pattern as a 2.8L or the 3.4L.

Edit: Sorry I didn't see the T5. I don't know as I have seen a T5 bolted to a Chevy engine as a stock configuaration. The rules for drivetrain swaps are strange. I remember when WI wanted to become another CA, and the rules made no real sense.

Ron

fasteddieyj said:

Why in the hell would the smog nazis care what tranny your running as long as the engine still meets their standards?

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Rules is rules and you have to go to a smog referee to get it approved before you can license it. I am of the same opinion. But they put a tag on it that says it is now no longer a Jeep, but a 94 S10. In some parts of CA, it would be dynoed and would have to shift exactly like a factory S10

Zuki-Ron said:

If I recall my Chevy stats, the 4.3L is a 90 deg V6. It does not have the same bell housing bolt pattern as a 2.8L or the 3.4L.

Edit: Sorry I didn't see the T5. I don't know as I have seen a T5 bolted to a Chevy engine as a stock configuaration. The rules for drivetrain swaps are strange. I remember when WI wanted to become another CA, and the rules made no real sense.

Ron

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Some of the 3.8s in cars had T5s

pretty cool! I have same header in my BlaZeR-2, awesome set!

it's a Vortec or a old school TBI or carb?

Vortec. 190 base hp. I'm running the headers, true 3"exhaust, Spintech muffler and Bosch +4 plugs. Should be an honest 230 hp

4.3LXJ said:

Vortec. 190 base hp. I'm running the headers, true 3"exhaust, Spintech muffler and Bosch +4 plugs. Should be an honest 230 hp

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let me tell you, PLEASE get these Bosch +4 plugs out and throw them FARRRR away and get get a better plugs like AC Delco platinum or Autolite xtreme (iridium) plugs! the 4.3L dont like these multiplies electrodes on the boschs!

what kind of fuel system and intake manifold you're gonna to use?

Stock vortec What is it they don't like about the plugs? Those are pretty impressive on a dyno in fuel injected engines.

4.3LXJ said:

Rules is rules and you have to go to a smog referee to get it approved before you can license it. I am of the same opinion. But they put a tag on it that says it is now no longer a Jeep, but a 94 S10. In some parts of CA, it would be dynoed and would have to shift exactly like a factory S10

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All I can say is WOW.
Good luck to you on getting it legal.

It won't be a problem. I spent some time with a referee so I wouldn't have any issues. One of the things is that if you stay with OBDI engines, then there is less to do than with OBDII. In 95 Chevy went to a crank position sensor. I wanted to stay away from that. So that leaves 93-4 in the sweet spot with the most horsepower and fewest issues to deal with. This one is a 93

4.3LXJ said:

Stock vortec What is it they don't like about the plugs? Those are pretty impressive on a dyno in fuel injected engines.

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the engine will run with it, but not as good, or smooth as stock AC Delco plugs that came with them stock.

Stock vortec? I wonders what you do about fuel system? use the crappy poppet injectors or MFI or marine intake manifold or carb?

I will be using the poppet injectors. Smog laws you know.

IF you ever have problem with the poppet, there's a MPFI kit to replace the poppet injectors. FYI the poppet injectors are as good as the MPFI if they're working fine so you wont see any improvement if you switch to the MPFI when yours poppet injectors' working fine.

Interesting. I did not explain it, but mine are new. However I will be bumping the horsepower up to around 300 next winter. How are those as far as capacity? I have a spare to tinker with with fuel pressure and so forth. But knowledge is the key to success.

Who makes these and how much?

By the way, that one is for a V8

yes, there's one for the V-6, they go for about $300-$350 IIRC at gm direct parts. The downfall is they dont flow any more than the poppet so you may not get enough fuel when you start to add more air (blower), which where the marine intake manifold come in. they're the true MFI, VERY easy to swap the injectors with the higher flow units. But this part can be a problem with California's strict emission inspection though.

I have a spare 4.3L that I left on the back burner for almost a year now that I really want to build it up to push about 300 hp without a blower and can be used with nitrous down the road in my BlaZeR-2 or some other toy I may put it in instead.

There are some good articles in Hot Rod.

http://www.sporttruck.com/techarticles/0110st_horsepower_upgrade/index.html

http://www.hotrod.com/pitstop/hrdp_0705_pitstop_chevrolet_v6_performance/index.html

http://www.hotrod.com/techarticles/engine/113_0208_chevy_43l_262ci_v6_engine_build/index.html

http://www.cfm-tech.com/chevy-vortec.htm

95' heep said:

I have a spare 4.3L that I left on the back burner for almost a year now that I really want to build it up to push about 300 hp without a blower and can be used with nitrous down the road in my BlaZeR-2 or some other toy I may put it in instead.

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The nice part about the MPFI set up is that it is manifold pressure sensitive. As the manifold pressure increases, so does the fuel pressure and capacity of the injectors. That is how they were able to get away with the Syclone engine with the addition of the turbo to get 290 hp

the best part is you got the vortec cylinder heads so you have more potential to make more power over the scylone engine with a blower (id rather a super charger for a off road vehicle)