Because with more power you can stay at lower rpm's to stay at the same speed.

 

so i should put a v10 in my jeep?

 

Well it only works at certain rpms because the more wide open the throttle is the more fuel and air is used correct? If you could fit a v10 in a cherokee than you definatly wouldn't have wanted it for fuel effeciency seeing as thats a lot more power than what im talking about.

 

your theory of more power = more fuel is great, as long as you don't factor in efficiency, modern fuel injection, or general common sense...

it is not uncommon, especially in the realm of modern v8 engines (lsx) to get more power and also greater fuel efficiency. I know this because I've owned 2 lsex cars and 1 lt1 car (supercharged at that). all of which gained mpg and power equally.

explain to my why the lsx guys (especially the vettes) can add 175 crank hp to their cars, utilizing huge cams offering 25*+ overlap and tons of reversion with use of a crossover polymer intake, yet get better mpg when everything is said and done? not because it's a myth..

for example my last bolt-on ls1 car got 24ish mpg mixed when it was near stock. I added roughly 80 crank hp to it and in the process boosted my mpg to 27. I saw over 30 mpg on the interstate @ 80 mph.

there's no reason a jeep can't do the same thing, but it won't happen without KEEPING THE AFR in check.

 

don't really understand why anyone would compare a 'modern v8 engine' to a tractor motor like a 4.0...thats stupid. some guys replace their 4.0 with 'modern v8's'...so i don't understand your logic.

key word = modern

 

the key principle regarding air/fuel ratio is what needs to be compared, not the engines themselves.

not to mention, the engines i'm using as examples debuted in 92 (lt1) and the ls1 was avail in 97. not so "modern" I suppose..seeing that these jeeps were also still being produced.

 

going back to what the op was proposing...worth it to hop up a tractor motor?

if i want my 4.0 to go fast, i'll put it on craigslist for a couple hundred bucks. then fill the hole it left with a 'modern' v8.

 

To answer one of the original questions. For less than the cost of a v8 swap I can guarantee our straight sixes can make more power than any of us will probably need. You can squeeze 250-300 horsepower out of a stroker. Unless your pulling 35s and 1 tons then theirs no reason you would need more than that. Any modern V8 swap and you have to worry about upgrading your driveline, axles, making a custom wiring harness, and worrying about making custom trans and motor mounts. And most modern v8s arent even compatible with our electrical system. So it just seems to me like stroking the original engine is a lot less work and money.

 

reliably?

upgraded/custom wiring, motor mounts, transmission mounts, and axles on a jeep?!?!?! never seen that before.... oh wait, i have, and all behind a 4.0.

 

A properly built stroker will be just as reliable as the stock engine yes. The second part of the quote I don't quite understand. Perhaps you missread me? I'm sorry I was thinking of the majority of people on here that don't already have swapped axles/trans. I don't want to have to build a monster mud or rock crawler just to have more power than I need. Also why would you need custom wiring on the stock engine?

 

Dont get me wrong i'm not putting the v8 swap down I just think it has its place. Would a swapped in 350 be better than a stroker in a mud bogger or extreme offroad courses? Any day of the week and twice on sundays that is if your looking for the most power you can get. Would I go through the trouble to swap a big 350 into what I plan to be my daily driver? Definatly not. Why? Because I don't have the time, the equipment or the funds that it takes to build one. And I dont even need that much power. That was the only point I was trying to make.

 

it takes time, equpiment and funds to do a stroker...and just because a v8 has two extra cylinders doesn't mean it's relegated to mud pits and extreme off road courses. a point was brought out earlier that a tuned ls motor is actually a pretty efficient engine....my point is strokers and bpu's are not worth the hassle on a 4.0. if you really want reliability AND extra horsepower, swap in something that rolled off an assembly line with 250-300 reliable hp to begin with. i wouldn't waste my time doing head work, forced induction, displacement increases and such on a 4.0. i would daily drive an ls swapped xj in a heartbeat. face it, you would too.

 

The heads and intake manifold can't support a 4.0L let alone a 4.6L.
4.0L 190hp/220tq, 4.6L is 15% bigger displacement and can expect only about 12% increase in hp and tq. Don't believe the stroker hype. They do make good tq and are great for that, but not much more hp. I haven't seen any dyno sheets to support the 250-300hp claims.

 

how much $$$ do you have in your supercharged motor? just curious for cost comparo.

 

Sprintex system is overpriced but I like the hardware and packaging-'priceless'.

Now doing another, '99 2WD AW4 lower street bruiser, going to install M62 with 6 pounds boost, complete install, tuned is under $2k. Will add +60-70 hp and tq.
And it is easily removable and revert to stock for resale if needed.
Try that with a stroker.