yes i am new here, yes i have searched previous posts, yes i read 15 odd pages of threads and found some answers, and here i am asking another question or two.

i'm working on my new project a 78 cj-5 258, it is pretty much stock (since i just bought it), i have done the tfi or tr or whatever you guys call it here (ford 300 parts on the dist and tfi coil), i have put on an msd6a.

i recently acquired an offy dual plane intake and a header for a pretty good price. was planning on dropping a q-jet on the offy, but have since decided to try putting together a tbi. i have the majority of the parts that i will need, but have a couple of questions as far as intake and exhaust...

1) the offy intake... i know that if i use it i will need to get a tbi to 4bbl adapter, no biggie, but should i bother or do i put the new intake on ebay and help pay for the parts?

2) the header... i realize that headers are typically for high end and really dont do much for crawling, etc, and that i am going to have to weld an O2 bung to the collector, but again, i have them so do i bother keeping them, or keep the exhaust manifold?

any suggestions, comments, finger gestures:eek: , are welcomed. thanks,

-web

Personally, I would ditch the intake for sure, just use the stock one with a 1 or 2 BBL TBI unit. I don't think you would be able to spit the difference in performance with the Offy intake. THe header, I dunno. If you drive it daily and/or to the trail, you might want it for a little bit more top end. If it's merely a trail machine, don't bother, you wouldn't see any gain over the stock manifold.

Oh and :flipoff2: WELCOME!!! :D

I'd ditch the whole engine and put in a 350... :flipoff2:

By the time you get done pissing around with the 258, you'll have spent enough time and money that you could've just installed something better. Take it from me.

Just a thought,
Jake

well i would love to put an 8 in it, but since i have an original 78 that only has 62k miles on it and so far i've been able to find everything (intake, header, tbi junk) for next to nothing, and the stuff that i did spend money on (msd) i can use with an 8 i'm gonna screw with this engine until it dies or pisses me off then i'm going for a 302 HO. but thanks for the suggestion.

btw do you know if its worth it to keep the offy intake with the tbi or not?

thanks,

-web

I have no experience with the Offenhauser intake, but I've heard they're more of a high-end power booster than a low-end torque booster. Just what I've heard, mind you...

As far as the TBI goes, that sounds like a great idea if you can get it to work right. (since you haven't mentioned the word 'Howell' I'm assuming you're piecing a system together from another vehicle.)

As for whether or not the two will work well together, I have no idea. My gut wants to say no because of the large intake size and the fact that TBIs don't generally pump a whole lotta GPM. If the TBI is off a V-8 there's probably a greater chance of it working well. Still, I'd sell the Offy to pay for parts like you said.

Like I was saying, I went down the same road (trying to get power out of a 258) with the GM HEI and a Weber and few other mods, but the engine eventually gave out from underneath me. Of course it had 160K on the original build. Since yours has less miles, you're probably safe there, but until you tear it down and rebuild it with better internals and a stroker kit, it'll never be a powerhouse.

I still say you should sell the engine and all your stuff and get a V-8. By all means, if you like Fords, get the 302 HO. That's a good engine too.

HTH,
Jake