planning on my first jeep

so i got a yj a few years ago and its all worn in it has 240 thousand miles and its tired the 258 isnt putting out the power it used to and im wondering how much power it used to put out compared to now. i was debating about putting in a v8 for a while to get the power out of it i wanted but just hopping up the 258 would i be happy with that?? rebuild bottom end with new head new cam new intake new exhaust. also i have the early yj and it has the Peugeot transmission witch is garbage and i need to put a new trans in it ive been looking at t18 for the indestructible ford trans and a first low gear i dont do much highway transit and its not going to be my only vehicle so cruising at 65 doesnt mean alot to me i was looking at the nv4500 but ive heard its too long and it wont fit in jeeps. i want something bulletproof that can take a beating. also my rear axle is a d30 and i havent heard anybody say they were really happy with that axle just really happy they got rid of it. id rather have a ford parts in it so i was looking into a 8.8 or d44 or d60 the 9 inch is to low of a yoke so thats out the question with that little driveshaft its only about a foot long as it is and im planning on lifting the jeep 4 inches or so with some 33 or mayb 35 im not exactly sure yet what these things are capable of. what have you guys done and what are you happy with. all input is appreciated. feel free to call me out on something that sounds dumb i can take constructive criticism

Quote from cj8

Wooo. That is a very intense post. d30 rear, I think you meant d35?
Sorry, I've got a CJ. My 258 was rebuilt with a larger cam to accommodate the 4.10 gears and 35" tires. It is possible @ approx. $1,500. Be careful. It changes the carburetor settings. I run richer and have to make adjustments for the DMV.

I don't know how or if the Dana 300 matches to your transmission but, I have been very satisfied with it since I've owned it. Still have done nothing to it (1982 CJ-8).

Lot's of information and lots of individuals here to help. When you are ready to "wrench", let us know.

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yes d35 i mix them two up sometimes i was in a hurry the other day typing that up as i am in now. did you get a new head on youre 258 cj8?? i have read about putting a 4.0 ho head on a 258 for bigger valves. is that worth while or is it not worth the money and pain to swap the other head in?? also i read that on an 87 and earlier 258 they have 7/16 head bolts and the 4.0 ho head has 1/2 head bolts but i know theres places out there that makes bolts to do that or the other option of tapping the block holes bigger to 1/2. i have heard great things about a d300 i heave heard of one weak point but i also read a guy put stock u joints on his axles hoping they would brake first before his transfer case did. i think my stock transfer case will work i have also read about a tailshaft shortening kit for the np231 so its shorter thats another good thing about the 300 is its not as long as the 231. im doing body work on another project right now im working on and im not "wrenching" on this jeep for a while. im just planning everything out and gathering parts looking for good deals.

Quote from Slimer

I went with Dana 44s from a late '70s Wagoneer. The width is about right. Just need wider flares which I have. T18 is a great tranny but if I recall, the ones out of a Ford will have a long input shaft. I got one from a CJ which fit perfect of course. There are others though which are good as well. I think the SM465 is popular. Consider the a tranny that will bolt up easily to the motor you choose. I've seen some people do a Ford 5.0L which seemed pretty sweet. To build up your I6, look at Hesco. They have a lot of info and parts available. Price everything you want to do to the motor and then price getting a stroker motor already done. A 3 speed T150 is also a strong as hell tranny. It's essentially the same as a T18 only without the extra gear (granny gear).

yes the wagoneer axles are an inch wider on each side i bileve arent they?? thats not much and i was wanting wider flares any way im from md but live in de now and im used to md cops giving me a hard time about my tires sticking out. the ford 5.0 is kinda a pointless swap you might as well go with the 4.9 straight 6 its the same size some of the ford 302 motors are. actually a 302 is 4.8-5.0 not many are actually a 5.0 ford just called it a 5.0. i have thought about putting the ford straight six out of an 80s truck in my jeep as well its the same displacement as the 302 but straight 6's get more torque and thats what its all about is off idle torque. also with that i wouldnt need an adapter for the t18 and a local junkyard has a few t18 sitting arround in md. they are all 2wd trans tho but i have seen parts to make the output shaft longer to accomidate the transfer case. the point of getting a t18 is for the low gear to get more power and be able to have higher diff gears so cruising at 50 doesnt burn up an entire tank in 4 miles... sorry these posts are pretty intense but i have been doing alot of research and havent really talked to any body about this till now. i joined another forum and they didnt help me much i didnt expect as much help as you guys have been and ive only been a member for one day. i dont waste time in wasting other ppls time to learn me something. thanks guys

Quote from cj8

Sorry it took so long to get back to this.
Yes, I put a 4.0 L on the 258. I could not tell a difference and a compression test yielded approx. the same as the 4.2 L head I replaced. The reason I made the swap was because I had to take the head off to repair 2 lifters that came off the 6th cylinder. I was able to reuse the same head bolts. I'll see if I can't find the "write up" I used.

Don't forget...let us know when / if you want help wrenching.

well the 4.0 ho head i thought was used to get greater cfm and let the cylinders breathe better. i havent heard about better compression out of that swap. and im guessing i would have to run fuel injection with that swap to that seems kinda expensive going from carburetion to fuel injection. do you notice a difference between the 2 setups? im trying to do this on a budget and not get to carried away. not sure what that budget is yet but im trying to minimize cost. im not trying to cheap out but just minimize cost a bit. my chevelle started out me thinking it would be on the road in a year and after a few thousand dollars. here it is 3 years later and 10 thousand invested and its still in the garage at my dads house. im trying to avoid that happening again. i want this thing outside my appartment last week if you know what i mean. thanks alot when i start tearing stuff appart ill let you know. prob start a build thread about it. but i mainly want this thing to be on the road and the first thing i need to do is the engine so it will pass emissions and get rid of the horrible valve tap i have going on. thanks again

Quote from bluedragon436

Hey since you were talking about swapping a 4.0 head onto your 4.2 found this the other day when I was looking into the same thing for a YJ I have been looking at purchasing thought you might like it. http://www.off-road.com/jeep/n…ead-conversion-29337.html

wow thats step by step how to do it and everything i could ask about the swap. thanks alot im going to start looking for a 4.0 head now. even said he used a carb so im ready to jump into that. i wanted to keep it carb and take off all the emissions. id rather use a screwdriver than a laptop to adjust my jeep but thats just my personal opinion. some ppl use fuel injection very well. thanks alot thats a great link i havent seen that yet

Quote from shorebird

You're doing the right thing asking for input. The questions I would ask you are (1) do you intend to keep the YJ street legal? If so what are the inspection and emission laws in your state. (2) Are you gonna run rocks, mud, sand? (3) Are you keeping her spring under, and if so which lift are you considering? (buy the best RE, BDS. etc.). These are just a few questions, and I would start building around 35's you're gonna end up there anyway. Have fun with the project

allright well... im keeping the jeep street legal and if delaware wont let me pass it through emissions my sister will let me use her address im sure to title it in md. i have some friends with some property i might do some wheeling there they have some pretty hardcore woods in some areas and i like mud sometimes but id like to give rocks a try never been on rocks before. i dont wana limit my buildup on my jeep. im thinking of going springover and keep the leaf springs. last lift i got was a rough country lift and i was pretty happy with it my truck handles pretty well but i cant wait to get the jeep on the road and sell it. im planning of using this jeep mayb as a daily driver for a while but i have 3 vehicles right now altho only one on the road. youre keepin the peugeot. thats a trans i cant wait to get rid of. you happy with the power from the 258 with the 35's and 456's i thought of going a little bit lower than 456 mayb 410 or 390. you think i might be happy with that gear or is the 456 gear in the diff a must with 35's?? if not an sye is youre tcase droped at all?? i was thinking of going 4 in of lift and looking for a fender that increases ground clearance and lets me keep her on the road. thinking of using an sye too.

thanks alot guys

Quote from Slimer

T18 is a great tranny but if I recall, the ones out of a Ford will have a long input shaft. I got one from a CJ which fit perfect of course.

thanks for that i didnt even think about it and i have been looking into it and i found on novak industries webpage that of all jeep t18 the smallest jeep t18 is 7.43 in of stickout. if im reading right it says from 76 through the year 79. and the ford standard stickout is 7 and a half on all ford t18. the ford is more standardized and jeep changed theyre t18 so many times and i read some jeep t18 out of scramblers wont work in jeeps because they have a longer input shaft. its only a difference of .07 between the jeep and ford t18 and thats the smallest jeep t18 input shaft thats arround a 1/16 of an inch i dont think thats a big difference i can live with that and the ford t18 is more standardized and easier for me to come by anyway. i found that the t150 and t176 bellhousing will work with one bolt moved down. just fill drill and tap. i would just rather go with the ford t18 because its standard with the low granny gear and input shaft and it will bolt straight up to my np 231 and to a d 300 just easier to look for rather than making sure it has the right first gear ratio and input shaft length. i dont trust people selling me things they are trying to get rid of just out of personal experience. just worrying about the output shaft length is easier for me that and making sure its not a t98 or t19
thanks