bobvonbob wrote:
> hey all - 87 YJ 258 - just did the ol "nutter" and i am bit confused as
> to one thing:

Oooff two years ago I was right where you are now... With an 88 YJ. It
starts getting expensive from where you are on out... For what it's
worth here's my opinion: my YJ currently is entirely new from the Cam on
up, ignition (TFI), Holley fuel injection, exhaust and header, new 4.0
head, lifters, timing set, hesco RVOB camshaft only the crank rods and
pistons haven't been replaced. And needless to say all that vacuum crap
is totally gone.

So having prefaced that with my experiences, do yourself a favor and
Swap a 350 in it or get a 4.0, or get a 4.0 and stroke it with your
4.2's crank and rods.

The 4.2 is a TURD. Especially in the YJ's and late CJ's with early
emissions systems. Even with mods and fuel injection it's a woefully
underpowered motor if you've ever driven anything with 200hp or more.

The 4.6 stroker in my XJ might actually be quicker than my old 95 GT
Mustang with 5.0 V8. (These were heavier than earlier GT's and the last
couple years of the 5.0 weren't it's best) they put out right under 200
hp (rear wheel) about the same as my stroker, and the XJ weighs less and
has taller 4.51 gears.

If you're just trying to keep your YJ running then good luck and sorry
if I wasted your time, but if you're after more power and performance
then punt as soon as you can :)

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

 

bobvonbob wrote:
> hey all - 87 YJ 258 - just did the ol "nutter" and i am bit confused as
> to one thing:

Oooff two years ago I was right where you are now... With an 88 YJ. It
starts getting expensive from where you are on out... For what it's
worth here's my opinion: my YJ currently is entirely new from the Cam on
up, ignition (TFI), Holley fuel injection, exhaust and header, new 4.0
head, lifters, timing set, hesco RVOB camshaft only the crank rods and
pistons haven't been replaced. And needless to say all that vacuum crap
is totally gone.

So having prefaced that with my experiences, do yourself a favor and
Swap a 350 in it or get a 4.0, or get a 4.0 and stroke it with your
4.2's crank and rods.

The 4.2 is a TURD. Especially in the YJ's and late CJ's with early
emissions systems. Even with mods and fuel injection it's a woefully
underpowered motor if you've ever driven anything with 200hp or more.

The 4.6 stroker in my XJ might actually be quicker than my old 95 GT
Mustang with 5.0 V8. (These were heavier than earlier GT's and the last
couple years of the 5.0 weren't it's best) they put out right under 200
hp (rear wheel) about the same as my stroker, and the XJ weighs less and
has taller 4.51 gears.

If you're just trying to keep your YJ running then good luck and sorry
if I wasted your time, but if you're after more power and performance
then punt as soon as you can :)

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

 

bobvonbob wrote:
> hey all - 87 YJ 258 - just did the ol "nutter" and i am bit confused as
> to one thing:

Oooff two years ago I was right where you are now... With an 88 YJ. It
starts getting expensive from where you are on out... For what it's
worth here's my opinion: my YJ currently is entirely new from the Cam on
up, ignition (TFI), Holley fuel injection, exhaust and header, new 4.0
head, lifters, timing set, hesco RVOB camshaft only the crank rods and
pistons haven't been replaced. And needless to say all that vacuum crap
is totally gone.

So having prefaced that with my experiences, do yourself a favor and
Swap a 350 in it or get a 4.0, or get a 4.0 and stroke it with your
4.2's crank and rods.

The 4.2 is a TURD. Especially in the YJ's and late CJ's with early
emissions systems. Even with mods and fuel injection it's a woefully
underpowered motor if you've ever driven anything with 200hp or more.

The 4.6 stroker in my XJ might actually be quicker than my old 95 GT
Mustang with 5.0 V8. (These were heavier than earlier GT's and the last
couple years of the 5.0 weren't it's best) they put out right under 200
hp (rear wheel) about the same as my stroker, and the XJ weighs less and
has taller 4.51 gears.

If you're just trying to keep your YJ running then good luck and sorry
if I wasted your time, but if you're after more power and performance
then punt as soon as you can :)

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein