Thinking out loud... bolt-on 4.0

[Root Moose]

I want more oomph for pulling my race car trailer (~4800 lbs) without re-engineering the universe. Buying a new truck is a non-starter.

I like my Jeep - works fine the way it's built. I need a bit more hp to overcome the aero drag from the lift and stuff at lower highway speeds (~100km/h) when towing and seeing long grades. The AW4 hunts a bit some times.


2001 4.0 (completely stock except for a 0331 re-pop head with the weaknesses removed)


Yella Terra rockers

CAI

header, high flow cats and exhaust

240 HP? 280 lb-ft?


Port and polish the stock head would be worth how much more?

Another 10-15?

I still have plenty of compression with 270,000 kms on the engine so no need for a stroker rebuild yet.

Whaddya think? Worth the effort to do the bolt-ons?

I heard a rumour the Yella Terras are worth 1-2 mpg when unloaded. Any real world truth to that?

 

[SolarBell]

If you can get 240 bhp (which translates to around 190-200 rwhp) with just rockers, intake, header, and new exhaust setup - then I'd love to hear about it. That is a 45-50 hp increase over the stock HO engine. I've got an intake, 99+ header, and an exhaust, and mine still struggles a good bit pulling my 3300 lb camper. Hence my project to install a supercharger.

 

[Talyn]

You might get 20 hp out of that if lucky. ~150-160 rwhp.

 

[rav]

The only way I see you getting 240 hp is if you stroke it to a 4.6L or what SolarBell said ie a superchrager.

 

[Dr. Dyno]

2001 4.0 (completely stock except for a 0331 re-pop head with the weaknesses removed)

Yella Terra rockers

CAI

header, high flow cats and exhaust

240 HP? 280 lb-ft?

Port and polish the stock head would be worth how much more?

Another 10-15?

On an '01 4.0 model you can expect something like the following flywheel nos.

215hp/266lbft:

CAI, 62mm TB, header, high-flow cats, 2.5" exhaust, clutch fan delete

226hp/270lbft:

Above + ported 0331 head

234hp/305lbft:

Above + poor man's 4.6L stroker