505 performance

How about a writeup on the 505 performance 2.5-2.9 stroker kit for the common 4cyl. YJ.  Followed by the addition of the pro-stock cylinder head.
Real world direct comparisons would be welcome.  

First, we've worked with 505 Performance in the past and believe in the company and its products. Good stuff, for sure. However, unless you're competing in some class that requires you to keep the four-cylinder, I can't really see the reasoning for dumping a ton of money into a 2.5L considering what you wind up with at the end.

505 lists the four-cylinder stroker kit for $1,700 with rods, pistons, cam and injectors. That's a great deal, although it doesn't mention the crankshaft. I'll just assume the crank is included and the omission is an oversight on the part of whoever designed the web site. If not, add at least another $500 for the crank and balancing.

That brings you from 2.5L to 2.9L. Figure at least another $500 in machine shop labor (that's conservative estimate) and then another $575 for the ported head to take advantage of the new cubes.  With gaskets, etc you're looking at a $3,000 four-cylinder buildup that'll make less than 200hp and 225lb-ft (I'm assuming...and I think being VERY generous - I haven't seen any published 505 numbers).

Add a bit more money for fuel system modifications and/or tuning to get the stroker to run right in the chassis, header, etc and you're banging on the door at the cost of a $500 take-out 5.3L, $500 in cooling and mounting products, $1000 for fuel system/electrical harness, and $1,000 in adapters to get it installed and running in your vehicle. The 5.3L will pump out a minimum of 285hp and 315 lb-ft and should prove more economical in terms of mpg.

I left out transmission upgrades for the 5.3L because you'll need them for a more powerful 2.5L as well since the AX5 is marginal behind the four-cylinder's factory 120-ish horsepower rating.

Again, if you're class racing and need to keep the four-cylinder it's great. However, I just don't think the costs and hassle are justified for the everyday 2.5L owner.  
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Editor
Jp Magazine
www.jpmagazine.com

I understand the logic of a 5.3 swap. But then the same logic would apply to running an Old Cj when you could drive a TJ instead for less money than it would cost to make it ride like one. I like my 2.5. It flys in the face of logic. I embrace the lightweight aspect and want to do super 35/30 up grades and a SM420/11.7 Atlas with 4.88's and 33's  400 to 1 crawl ratio.. Why? Why not. I would bet there are a ton of readers driving 2.5's out there and many like myself like them and feel like the giant killer when we make a hill that a 4.0 might not have. We are like the Turbo VW's who line up at the track against 350 chevys. Why?  We dance to the different drummer. Ours is a passion that does not make sense. But then who in their right mind puts 20,000 into a 92 YJ 4 popper. Only a hard core Jeeper who thinks Jeeps were created with 4 squirrels and who are we to change that. A 2.9 offset ground crank kit with a ported head and Intercooled turbo would positively float over rocks.  Anyway thats the plan.  

DoorGunner - we're kind of making the same argument from different sides of the fence. You've hit upon a couple of my arguing points regarding the 2.5L. I'm not saying to junk your 2.5L. In fact, each of the Jp staffers owns a 2.5L-powered Jeep (several in fact). I've got a TBI-injected '89, Verne Simons has an MPI 2.5L TJ and an MPI 2.5L '56 CJ-5, and Trasborg has several MPI 2.5L YJ Wranglers...one of them running a 505 turbo kit. They're great, light, durable little engines. BUT if power is what you're after (like the stroker kit and associated buildup parts) it doesn't really make economical sense to me. Your money is better put into deeper axle gears (like we've been saying in the magazine for years), a tranny swap (Verne is actually working on the SM420 conversion with his 2.5L TJ right now), and perhaps other low-range gearing options if you're into crawling.

If power is your goal, trying to get any appreciable increased output from the 2.5L usually isn't worth the return on your investment when there are other, better, cheaper options available...like a V-8 or V-6 swap or something different that can offer more output for a similar financial outlay. And as far as the weight is concerned, an aluminum-block 5.3L (like the LC9) isn't actually that much heavier than the 2.5L.

Again, keep your 2.5L and love it if that's how you feel. And stroke it if you've got the bucks and that's what you want to do. But as far as doing a story on something like a 2.5L stroker buildup (which was the original point of this thread) I don't really think it's in the best interest of the average Jp reader.  
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Editor
Jp Magazine
www.jpmagazine.com

Economical sense or not, I read on forums and sites all the time where people want to improve the performance of their 2.5.

From what I read in JP, any swap will require a different trans, different transfer case input, different axles, drive shaft mods, and cooling mods.

When time comes to rebuild the 2.5,,,why not upgrade??  

I agree here; I have the 2.5L, and I do get an extra bit of pride when I get across obstacles that others with the 4.0L could not cross.  Does it make economical sense?  No, but then again, do most of the mods we make to Jeeps make economical sense?

I looked into turbos, but I am not a big fan for 2 main reasons: 1. the lag, and 2. they tend not to work so well at the lower RPM range, which is where most of the wheeling I do happens.  I wheel in Costa Rica, and even with all the mud here, my trusty four banger has beaten every obstacle I have thrown at it (granted, sometimes with the help of my Superwinch, but still...).  I have been up to the doors in mud, and I have clawed my way up muddy hills where 8 cyl Jeeps had trouble climbing.  

I am now looking at overhauling the little engine that could, and I am seriously looking at the kit from 505 performance.  If I had a bit more information, I would have probably pulled the trigger on it already, but as it is, there are too many question marks to throw that kind of dough at without having an answer to.