Howell TBI, emissions or not?

[grand_wag_85]

As far as fuel mileage goes which kit from Howell would produce better results? The offroad kit or the California kit? I'm planning on injecting one of my 258's and am not sure whether or not to leave all of the emission stuff in place as there is no emission testing in the county I live in.

[FSJ Guy]

I'd go with the CARB certified kit. You never know where you'll end up moving around to and it'll be better to have it and NOT need it versus the other way around. I doubt mileage will be any different. Heck, it might even be better with the emissions version.

[Billygoat]

I think the only difference is the O2 sensor is heated on the CARB model.
Maybe the tunning is different, but I think it is more paying for the sticker.

[Jlamb]

There is also a vehicle speed sensor. This allows fuel cut on decel and the reason why it is CARB certified.

This is a good kit and if it were my rig I would go with the CARB certified, it is just a few extra bucks.

[Billygoat]

A heated O2 and speed sensor will set you back the price difference so in that case it is worth it - plus the certification you would not have if you added them yourself (plus you need to alter the program if you add the VSS)

[FSJ Guy]

He's got a 258. Isn't the CARB legal version basically a copy of the Mopar fuel injection that was available on later motors?

[tgreese]

He's got a 258. Isn't the CARB legal version basically a copy of the Mopar fuel injection that was available on later motors?

Nope. The Mopar fuel injection kit is based on the multiport (MPI) system used in the Wrangler. The Howell system is a throttle body (TBI) system using GM parts used on the 4.3L Chevy V6. Completely different. The prices are different too - the CARB approved Howell kit is about $1400, and the Mopar kit, also CARB approved, is over $2000 (likely well over now; I have not looked at the price in a while).

[FSJ Guy]

Nope. The Mopar fuel injection kit is based on the multiport (MPI) system used in the Wrangler. The Howell system is a throttle body (TBI) system using GM parts used on the 4.3L Chevy V6. Completely different. The prices are different too - the CARB approved Howell kit is about $1400, and the Mopar kit, also CARB approved, is over $2000 (likely well over now; I have not looked at the price in a while).

Got it. Thanks for the correction!

[babywag]

For a 258 I'd get a complete system off an XJ w/ a 4.0 including the head.

Could probably buy 3 or 4 set-ups, for the price Howell wants.

From what I've read about them the wiring is minimal & easy.

[tgreese]

For a 258 I'd get a complete system off an XJ w/ a 4.0 including the head.

Could probably buy 3 or 4 set-ups, for the price Howell wants.

From what I've read about them the wiring is minimal & easy.

Yep - as I recall, the Mopar kit comes with a manifold that lets you keep the 258 head. If you swap heads, you can use the XJ stuff. Too bad the forum about 4.0L transplants is gone. It's archived here: http://web.archive.org/web/200812231...sp?FORUM_ID=24 - but no longer any opportunity to ask questions. The strokers forum might be a good place for questions www.jeepstrokers.com You don't get the CARB sticker with the XJ stuff, if that's important.

[babywag]

True about CARB sticker, but you're using OEM approved parts.
Even in CA they would slap a sticker on it if it passed sniffer & visual.
I know a couple CJ people that have had no problem with the smog police after converting.

[grand_wag_85]

I'm leaning towards the XJ system as I have two 258's that I'd like to covert without killing the wallet. One is in an Eagle with a functioning carter BBD and associated sillyness and the other in the J10 with nothing original. The thing that scares me more than anything else is the wiring.

For the FSJ don't you need to run HB to clear the 4.0 intake? Never really looked into it but what is the cost like?

[babywag]

HB is pretty cheap if you go used parts from Elliott, and buy new hoses etc.

I think I spent a little over $200, best upgrade money can buy for an SJ.1

[grand_wag_85]

HB is pretty cheap if you go used parts from Elliott, and buy new hoses etc.

I think I spent a little over $200, best upgrade money can buy for an SJ.1

I will look into that. How does one contact Elliot? His PM's are always full and the email feature on this site does not work IIRC.

[babywag]

I'll PM you his email address, that's always how I got a hold of him.