Muffler Sound

[Alexia]

I thought only regular 4.0's could be stroked. What are the costs vs. benefits of doing the coversion?

 

The only difference between the 4.0 and a 4.0 HO is a better cylinder head. All that has to be done to make a normal 4.0 into a HO is to swap a HO cylinder head on.(Plus potentially intake and exhaust...) With a straight 4.0 HO swap there is roughly a 15hp increase. Stroking a 4.0 HO will send it to whatever extreme you have in mind and have much money you have to spend.

[HOrnbrod]

The only difference between the 4.0 and a 4.0 HO is a better cylinder head. All that has to be done to make a normal 4.0 into a HO is to swap a HO cylinder head on.(Plus potentially intake and exhaust...) With a straight 4.0 HO swap there is roughly a 15hp increase. Stroking a 4.0 HO will send it to whatever extreme you have in mind and have much money you have to spend.

 

And that's a big difference for building a performance engine. The HO head flows better, and allows you fairly cheap bolt-on upgrades like the 99+ intake manifold and a varied selection of exhaust headers. Better suck and blow makes a stroker go.

[ftpiercecracker1]

With all that HornBrod and Alexia have said don't let it deter you from stroking your 4.0 if its not an HO. Every single jeep 4.0 head ever made will bolt onto every single jeep 4.0 block ever made. NOTE: I said 4.0 to 4.0

 

My original motor was the old school Renix, crappy head, crappy intake, crappy TB. To combat this I picked up a 7120 head, which actually requires you to run a different intake, so i got myself the better 99 manifold and ordered an overbored TB to match.

 

Now that this was all done the only difference between my motor and an HO was the fuel rail/lines and the throttle bracket. I understand what the guys are trying to say, but i don't think any one 4.0 would be the best its just which one is the easiest and provides you with the best starting platform. If that were the question then yes an HO would be the best way to go.

 

I know that the newer (unsure start year) 4.0 blocks have extra webbing in the castings, making them stronger, BUT paradoxically I have also heard the older 4.0 blocks, pre HO, contained a higher nickle content, superior internal wear protection. However the only one i can confirm 100% is the first one.

 

Really all this jaw jacking ( :rant:) is pointless, no matter what path you take a stroker is BA. Mine should be getting wrapped up in the next few weeks. 8) :driving:

[flint54]

RE: "If you want a Jeep I-6 to sound good ... go Gibson."

 

So pursuing this from a slightly different angle (since stroking isn't in my budget),

just which Gibson is being used? The only Gibson that comes close to the right

dimensions (2.250 in & out, inlet centered, outlet offset, oval body) is model 55141,

BUT it's too short. Their body is 19" long and mine is 21" long. My muffler is badly

buckled (don't ask how) and needs replacement. And, I'm not really after the sound,

I just want a good muffler that doesn't need replacement again soon (unless I

happen to buckle it - again). I like quiet.

[flint54]

And, their 19" length is actually total (includking the nipples). The body is only 13" where mine is 21".