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Hey MadScientistMatt...
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Posted by: John

...there was a site you referenced a while ago that has a bunch of performance parts for inline/slant 6 cylinder engines. I cannot remember the name for the life of me. I do remember though that they had parts for I6's from Dodge, Jeep/AMC and Ford. I know a guy who is looking to do a build up on a 4.0L Jeep block with a 4.2L stroker kit. I think he can use some parts from that site to reach his performance goals for the engine.

Posted by: bl3wbyu

Ooh, I'd be interested in browsing through the site, too, if it has parts for Jeep's 4.0.

Do I know this guy?

Posted by: John

Yeah, Frank Z. He wants to hit 275 horses and 300 pound feet and use stock intakes and exhaust manifolds on a ported head and he's just not going to get it using the stock lumps. He can get a header and aluminum intake manifold, save himself a bunch of weight and pick up his power gains across a broader spectrum but still maintain his low end torque with the 4.2 stroker kit.

Posted by: bl3wbyu

How high a displacement can you go with the 4.0 before running onto all those issues you listed on CP? Assuming I keep my Jeep, which I'm pretty sure I will, I will be interested in stroking my 4.0 at some point.

Posted by: MadScientistMatt

John,

That would be Clifford Performance. I'm running one of their older slant six intake manifolds on the Dart, reworked for EFI. Some cybersquatter grabbed the .com version, so here's their address:

http://www.cliffordperformance.net/

They are pretty good with Jeep performance parts, but aren't always the most prompt about shipping.

Posted by: bl3wbyu

Ooh, nice link.

Posted by: DeckSetter

The Jeep stroker can be made from a stock 4.2l (258, the old carb'd motor) crank and rods. That puts it about 4.5 or 4.6l. Stock 4.0l is about 190hp, just the basic stroker should put it well over 200hp with monster torque. There are a couple of guys on Jeepin.com that have built a stroker I think, but I haven't looked at that stuff in a while. I passed on the idea when my Cherokee started having pieces fall off at random.

Posted by: DeckSetter

4.0l stroker threads from Jeepin:

http://jeepin.net/forum/showthread....ghlight=stroker

http://jeepin.net/forum/showthread....ghlight=stroker

245hp, 330ftlbs out of the 4.6l stroker according to desktop dyno...
http://jeepin.net/forum/showthread....ghlight=stroker

Posted by: bl3wbyu

Ooh, thanks for the links, DeckSetter.

Posted by: John

See, told ya Frank isn't going to make his power goals with slightly modded stock parts. If he gets himself one of those ported intakes and a more aggressive cam than what he is planning then yeah, he'll see his 275 horses. As it is now though, he's better off going low compression and supercharging it for reliable power closer to 300. However, I haven't heard of people going past 300 horses with much success. The heads just don't have the geometry to flow well enough. Then again, those who are building I6's up are going for off-road capability. At 300 horses, that engine is probably putting out 450 pound feet of torque at probably less than 3500 RPM.

For info, from his post:

Quote:


	Dropped off a 4.0 block, 4.2 crank & rods at the machine shop a few days ago. Hope to get the port/polish done on the cylinder head soon too, then it's off to the shop for a little tweaking. I'm hoping for 265-275hp, 300ft torque. The motor will use a '99 intake with equal length runners, 21-24 lb injectors and the throttle body is going to get massaged as well. I haven't decided 100% on the cam yet, but I'm getting close. I'll be using an OEM exhaust (header, not a cast manifold). This is a stroker motor. The block is getting bored .030" and align bored, head is getting decked and a 3 angle valve job when I'm done porting it decked. The 12 counterweight crank (approx. 80lbs) and 707 connecting rods are from a late 70's 258, the block is from a 96 Cherokee, mileage is unknown. The crank is being turned approx. .020 and the whole shebang will be balanced. Total displacement will be 4.6l using Sealed Power cast hypereutectic pistons and moly rings. The stock exhaust manifold breaths very well, so much so that the down pipe has a dent in it from the factory to increase back pressure. 9.5:1 compression. The cost is still TBD. I'm in the process of port matching the head. the stock header will be used, unless I find a crack in mine. I replaced the stock muffler with a Flowmaster Delta 40. The stock exhaust is 2.5", so other than possibly replacing the downpipe at some point, there's no need to do anything else right away.

Noble effort for sure but I don't think it will be enough for 275 horses. Also, he goes on about smoking 5.0L Mustangs which is just not going to happen in a 4500-5000 pound Cherokee. A 5.0L Mustang may only have 225 horses stock but it only weighs about 3300 pounds. He's got a 1200-1800 pound weight disadvantage to overcome before his 50 extra horses can make a difference. It's a noble effort and I totally support what he is trying to do but he's making alot of bench racing claims that I really don't think he's going to be able to back up. I think he's setting himself up for a big disappointment.

I passed on the Clifford Performance link and he totally blew me off and ignored me. That's fine, nothing I can do about that. However, Clifford is pretty well known to those looking for inline 6 performance products. Then again, what is it they say? Those that don't know don't know they don't know? Not trying to be a know-it-all, just staying grounded in reality.

I also forgot about the 4.2L block. I've been told that the newer 4.0L will not go real big at all and that 4.6L is teh maximum it will handle. But the older engine I think is from the AMC years and a completely different engine. That can go big and I've seen resleeved ones get very close to 5.0L of displacement. Then again, that is really pushing that block too.

Posted by: DeckSetter

Quote:

Originally Posted by John


	See, told ya Frank isn't going to make his power goals with slightly modded stock parts. If he gets himself one of those ported intakes and a more aggressive cam than what he is planning then yeah, he'll see his 275 horses. As it is now though, he's better off going low compression and supercharging it for reliable power closer to 300. However, I haven't heard of people going past 300 horses with much success. The heads just don't have the geometry to flow well enough. Then again, those who are building I6's up are going for off-road capability. At 300 horses, that engine is probably putting out 450 pound feet of torque at probably less than 3500 RPM. For info, from his post: Noble effort for sure but I don't think it will be enough for 275 horses. Also, he goes on about smoking 5.0L Mustangs which is just not going to happen in a 4500-5000 pound Cherokee. A 5.0L Mustang may only have 225 horses stock but it only weighs about 3300 pounds. He's got a 1200-1800 pound weight disadvantage to overcome before his 50 extra horses can make a difference. It's a noble effort and I totally support what he is trying to do but he's making alot of bench racing claims that I really don't think he's going to be able to back up. I think he's setting himself up for a big disappointment. I passed on the Clifford Performance link and he totally blew me off and ignored me. That's fine, nothing I can do about that. However, Clifford is pretty well known to those looking for inline 6 performance products. Then again, what is it they say? Those that don't know don't know they don't know? Not trying to be a know-it-all, just staying grounded in reality. I also forgot about the 4.2L block. I've been told that the newer 4.0L will not go real big at all and that 4.6L is teh maximum it will handle. But the older engine I think is from the AMC years and a completely different engine. That can go big and I've seen resleeved ones get very close to 5.0L of displacement. Then again, that is really pushing that block too.

I've heard up to 4.9l out of a stroker. Don't know about the different blocks.

As far as weight's concerned, the Cherokee doesn't way all that much over 3000lbs. Ever been in one? They're pretty small, and unibody.

http://jeephorizons.com/tech/xjstockspecs.html
"Curb weight 4wd = 3,057 lbs - 3,386 lbs"

Posted by: John

Quote:

Originally Posted by DeckSetter


	I've heard up to 4.9l out of a stroker. Don't know about the different blocks. As far as weight's concerned, the Cherokee doesn't way all that much over 3000lbs. Ever been in one? They're pretty small, and unibody. http://jeephorizons.com/tech/xjstockspecs.html "Curb weight 4wd = 3,057 lbs - 3,386 lbs"

Actually, I think it's a Grand Cherokee. Sorry, my bad. I might be wrong though.

Yes, I have been in one before and they honestly don't feel that light. On top of that, they have a good deal of unsprung weight and much more drivetrain than a Mustang. That all factors in. Plus, your numbers there, the low end is likely for the 4 cylinder engine on the 2WD chassis. His big 6 with the older, heavier block and 4 wheel drive is probably passed the high end of your scale.

Posted by: bl3wbyu

What? You don't think it feels light?

Posted by: DeckSetter

Quote:

Originally Posted by John


	Actually, I think it's a Grand Cherokee

ooooo that's another animal entirely, probably close to another 1000lbs. Those weight numbers I posted are right in line with stock 4x4 Cherokees (the 2wd base models are listed right at 2900lbs believe it or not), but I think the ZJ (93-98 Grand Cherokee) comes in around 3800lbs. Don't quote me on that, I'm too tired to look it up at the moment (stupid benadryl...).

Posted by: John

I looked it up. The 4.0L versions weigh in at 3600 pounds and they can top 4200 depending on options packages. Maybe a little light than I thought but still quite a bit porkier than a Fox chassied Mustang. A newer SN-95 Mustang, yeah, it'd be all over it but a GFox chassied Mustang is just too light. Even the heavy GT's are still at least 600 pounds lighter than that and 50 horses will not make up for it.

Anyhow, yeah, I didn't think the Cherokee felt light. The main reason is all the unsprung weight. Those big wheels, beefy suspension parts and live axles are all heavy and they slow response. Off-road they are quite nimble but they never felt "light" to me. My Lightning feels light. I can throw that around a turn and it doesn't feel like it's 4700-4800 pounds. That doesn't have a whole lot of unsprung weight though and most of it is in the rear axle. Also, I'd be willing to bet that the chassis is stiffer too and that makes a difference also.

Now my Ranger, THAT felt light. It was only 2WD but I could take it places that most of my friends with 4x4 would go and it went like a mountain goat over some of the hariest obstacles. It was great in the mud too because it didn't sink as easily. Then again, weighing in at about 3200 pounds, it was fairly light to begin with. Also, teh unsprung weight was deceiving with the twin I-beam front suspension.

Posted by: DeckSetter

Quote:

Originally Posted by John


	I looked it up. The 4.0L versions weigh in at 3600 pounds and they can top 4200 depending on options packages.

Yeah, I could believe that in a Grand. My Cherokee was a Sport, manual windows and locks, not much sound deadener, etc. It felt really light to me, very nimble. Not sports car / pony car nimble mind you, but for an SUV with that much clearance underneath it felt like it really held the road.

The Grand is more in the category of an S10 Blazer. They put a lot more options on them. The only Grand I ever drove was a '98 with a 318 and full time 4x4. It didn't feel nimble at all to me.

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