DirtyComanche Posted October 14, 2007 Share Posted October 14, 2007 Who has done what? Handling improvements? Braking improvements? Weight savings? All around drive-ability? Just looking for ideas. Link to comment Share on other sites More sharing options...
TNT Posted October 14, 2007 Share Posted October 14, 2007 In a street truck I would start with a SWB MJ and add the following: ZJ upcountry coils with 1 coil removed The largest swaybar that an XJ uses 4.0HO stroker built and camed NP3500 NP242 transfercase Rear D44 with a detroit geared 4.88 ZJ rear discs In cab adjustable proportioning valve Front non-disconect D30 with a true track geared 4.88 WJ front knuckles and brakes Add a rear swaybar Custom stiff rear springs built for proper ride hieght Bilstein 7100 shocks 285/40ZR18 BFG KDW tires 18x10" forged alumium rims I could go on and on Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 14, 2007 Author Share Posted October 14, 2007 I was thinking similar things. OTher than I'd use a LWB. In the front I thought I'd use the V8 ZJ coils and hack them until I got about a 2" drop, and maybe about 170lbs rate. And use the ZJ anti-sway if it'll fit (not sure on that one). And probably use the WJ brakes/knuckles if I could get them. Otherwise, I'm not sure. And add a truetrac (have one on the shelf) and 4.56 gears. For the rear I think I'd use one of my isuzu 12Bs. They're lighter than an 8.8, have 4.56s, limited slip, larger than D44 axle shafts and disk brakes. And a sway bar. And probably a 4-link and mount the gas tank differently/elsewhere and use some cut down TJ rear coils. It should be lighter than leaf springs, and maybe better... I was thinking poly bushings for the front suspension too. But, any good ideas on weight reductions? Wheels obviously. Perhaps removing the factory carpet/sound deadening and replacing with dynamat (is it lighter, hmm?) and lighter carpet. Link to comment Share on other sites More sharing options...
over2land Posted October 14, 2007 Share Posted October 14, 2007 Having put dynamat in my 715, and just yanked the carpet and crap out of the MJ, I'd say straight across that the dynamat is heavier than the stock stuff... that is, if you are planning on putting it everywhere the stock stuff was. There is also a lot of weight in the dash and HVAC. Ditch the whole bed and get some fiberglass bedsides. Replace glass with lexan, or just lose the glass. Basically build a Jeepspeed MJ lowered to run on the street. FWIW, 4.56s and smaller than stock tires will make for like a 50mph top speed. Why not a 9-inch with aluminum center and lightened gears? Why LWB instead of SWB? . What is your goal for the truck? I guess I should have asked that first. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 14, 2007 Author Share Posted October 14, 2007 Something I can DD but have fun with... Decent power, AWD, and a lower curb weight than stock. So no removing the glass or entire bed. As tempting as it is. Lexan isn't street legal and won't survive wipers. But it'd be tempting for the rear window as it doesn't get abused. The HVAC/Dash can be removed/simplified, or entirely rebuilt, but looking at the stock parts there is little weight to be saved there if I want to keep a reasonable amount of fucntionailty. I should have weighed all the parts I took out of my trail rig. There is glass front fenders and a hood avaliable, AFAIK. They'd be worth a few pounds but would cost a considerable amount. And I haven't done the math on the gear ratio, but I doubt it would be that bad for top speed. I doubt any tires I put on it would be height wise smaller than stock (at least, not by much). 50mph = 80km/h. My MJ with 3.07s and a 5spd would tach about 2400rpm at 130km/h. That'd be like 3600rpm at 130km/h. But I'm not sure just yet. My transmission choice would be part of it... Link to comment Share on other sites More sharing options...
cherokee Posted October 15, 2007 Share Posted October 15, 2007 There are some ford coils that are virtually the same as stock xj coils with a similar spring rate and shorter length. I haven't actually tested this out yet so it's still sort of theory based. What are the advantages of the WJ brake/knuckle assembly? Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 The WJ had larger brakes. AFAIK you have to run the WJ knuckles to use them. Which makes life a little harder. Link to comment Share on other sites More sharing options...
TNT Posted October 15, 2007 Share Posted October 15, 2007 FWIW, 4.56s and smaller than stock tires will make for like a 50mph top speed. 50mph would be 2400rpm :nuts: 245/40-18's with 4.88 gears and a NV3550 would have a top speed of 110mph. And it would launch hard. The power would be great. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 I guess I could save a few pounds and maybe my back with some aftermarket seats. The stockers feel like they're 50lbs each... Link to comment Share on other sites More sharing options...
87manche Posted October 15, 2007 Share Posted October 15, 2007 aluminum driveshaft? that would save a few pounds right there, and it would reduce the inertia of the drivetrain. other than that, I can't come up with anything. I know addco makes some big beefy swaybard for the front. Rear, probably take something from a dakota. Link to comment Share on other sites More sharing options...
over2land Posted October 15, 2007 Share Posted October 15, 2007 50mph would be 2400rpm :nuts: And 2400 is right where I like to be for 70-75 mph, not 50. Regardless, I was throwing that out there not as chapter and verse, but just to think about it. There was talk of lowering, which normally brings smaller tires, which will increase the RPM. Really, we can all do the math, but without tire size, and transmission choice nailed down, its kinda pointless. 245/40-18's with 4.88 gears and a NV3550 would have a top speed of 110mph. And it would launch hard. The power would be great. I agree it'd launch wicked hard. But, I drive a lot of freeway. My 715 has 5.87s and 38's. Comfortable cruising speed in that truck is 55. Here, 55 will get you run off the road by even big rigs, whose legal limit IS 55. Anyway, I don't use the 715 much except for around town as a result. I couldn't imagine building a Comanche that would give me the same limitation that the 715. The Comanche is such a nice truck to drive comparatively I wouldn't want to ruin it by needing to run the thing at like 4,000 RPM (again, just WAG) just to maintain speed on the highway. That's why I asked what he was going to be doing with the truck. If highway trips weren't in the plans, and it was just going to be a canyon carver, the highway cruising didn't matter and you could gear the snot outta it and have a ton of fun. Link to comment Share on other sites More sharing options...
over2land Posted October 15, 2007 Share Posted October 15, 2007 On brakes, Vanco has a big brake kit out that I've been eyeing. It is kinda pricy, but maybe not a ton more than the WJ stuff by the time you done buying everything. Didn't the WJ have isssues with warped rotors? Anyway: http://www.vancopbs.com/product_p/dkj1000.htm And, depending on rear axle, TSM has some nice kits for decent prices. http://www.tsmmfg.com/Rear_Disc_Brake_Kits.htm I've put on the one for a 9-inch before and the install went well. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 The early WJ brakes would warp the rotors. They would however fit in a 15" rim. I'd probably run 16" rims at least anyways. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 aluminum driveshaft? that would save a few pounds right there, and it would reduce the inertia of the drivetrain. Very pricey though. But on a AWD rig there'd be decent gains from doing both. Although, maybe not? 6061-T3 tubing isn't that expensive, it's just if the ends are? I'd run the slip yoke in the rear since the NP242 sees no strength gain to a SYE, which makes for a cheaper/simpler driveshaft. However, the front would need a slip. It also comes down to te power output nunbers, because that would dictate my driveshaft size... It might be an idea for me to call tom woods/JE Reel/1-ton CV and see if they do aluminum and for how much? Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 Regardless, I was throwing that out there not as chapter and verse, but just to think about it. There was talk of lowering, which normally brings smaller tires, which will increase the RPM. Really, we can all do the math, but without tire size, and transmission choice nailed down, its kinda pointless. Lower =/= smaller tires. Not really at least. The stockers rocked 215/75R15s and 225s. I could fit those with a dropped truck with the suspension that I'm talking about. I can go to a reasonably wide tire too. It's not as big of a deal as an off-road truck where the tire moves all over the forking place as the suspension travels. At least, from what I've seen other jeeps with similar drops running. OD ratio would be somewhere in the name of .71 - .78. Not a huge difference. I only cruise at about 130-140 hm/k, the limit legally is 110. TNT would go about 10% lower in the gear ratio than me, but that's not a huge difference again. Like I said, I'd be in the rounds of 2400 in OD there. And FWIW right now I'd not be running a AMC I6 engine - they can't rev and that bothers me. Link to comment Share on other sites More sharing options...
feerocknok Posted October 15, 2007 Share Posted October 15, 2007 Something like a 4.3L maybe? Downsizing tires would be beneficial to reduce your rolling mass, and help out your breaking. Aluminum wheels would be a good choice as well. I don't think that an aluminum driveshaft would make up for the cash, but I also don't know how much $ we're talking. Running bedsides only, with no actual bed, would save alot of weight. Also, avoid power windows and door locks. Ounces lead to pounds. Pounds lead to speed. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 15, 2007 Author Share Posted October 15, 2007 Ounces lead to pounds. Pounds lead to speed. I've heard that before. But I don't think I'd ditch the inner bed, I'd want it still to be functional, at least reasonably. Power plant options aren't totally though out. Buick 3.8 turbo, the more modern EFI 3.8 (like jeepco's), or a 4.3L vortec perhaps. Also on the potential list includes a LT1, or a regular SBC. Both the V8s present other problems. But, it's all hypothetical so it doesn't really matter... Couldn't tell you for sure on the tranny either. Link to comment Share on other sites More sharing options...
Oizarod115 Posted October 15, 2007 Share Posted October 15, 2007 wow! 4.88s are deeper than stock on a 35" tire... holy CHRIST i can't imagine attempting to drive a stock truck with 4.56 much less 4.88 Link to comment Share on other sites More sharing options...
HOrnbrod Posted October 16, 2007 Share Posted October 16, 2007 Save weight by ditching the rear step bumper and installing an aftermarket tubular bumper, it's about 1/2 the weight. And the fiberglass hoods are actually a couple of pounds heavier than the stock hood. Street rig would look great with the Reflexxion cowl hood, same weight. I'm saving my pennies for one........ And Addco sways are overpriced. An XJ Country or ZJ V8 sway is as thick as the Addco for a whole lot less $$. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 16, 2007 Author Share Posted October 16, 2007 And Addco sways are overpriced. An XJ Country or ZJ V8 sway is as thick as the Addco for a whole lot less $$. So the ZJ one does fit? I'd have tried one before buying anything aftermarket. No tube bumper, would probably just make a roll pan out of aluminum. Not technically legal, but w/e. As long as it looked alright. Thanks for the warning on the glass hood's weight. Link to comment Share on other sites More sharing options...
HOrnbrod Posted October 16, 2007 Share Posted October 16, 2007 So the ZJ one does fit? I'd have tried one before buying anything aftermarket. No tube bumper, would probably just make a roll pan out of aluminum. Not technically legal, but w/e. As long as it looked alright. Thanks for the warning on the glass hood's weight. Yes, the ZJ V8 bar bolts on. The one I got is a bit over 1-1/8" thick. I don't know about an alum roll pan in the rear in your AO Dirty. Too much slippin' and slidin' in the winter; I'd want something back there. Link to comment Share on other sites More sharing options...
DirtyComanche Posted October 16, 2007 Author Share Posted October 16, 2007 I wouldn't drive it in the winter... I have a CTD to be my actual DD/winter driver. If I get a MJ to make into a street truck, I'd want it to be nice. The winters here quickly reduce vehicles to NOT being nice. So it'd just be a 6 month of the year thing, or something... Link to comment Share on other sites More sharing options...
TNT Posted October 16, 2007 Share Posted October 16, 2007 wow! 4.88s are deeper than stock on a 35" tire... holy CHRIST i can't imagine attempting to drive a stock truck with 4.56 much less 4.88 It would make a wicked MJ. Around me are mainly county roads with a 55mph max speed. Lots of tight twisty roads with 25mph-35mph rated turns. It would be sweet. :brows: The more I think about it the the more I think an AW-4 would be the way to go with some 295/35zr19's. :chillin: 110mph is just about perfect. With the 60 foot time it should run 110mph would be a good trap speed. 4.56 gears would be ok too. Living life a 1/4 mile at a time A better combo would be 4.10 frt gears with 275/35ZR19 tires and 4.88 rear gears with 305/40ZR22 tires. This would have a top speed of 130mph with 2500rpm at 65mph. That would be a 26.5"x10.9" front tire and a 31.5"x12.4" rear tire. Now that would be wicked Link to comment Share on other sites More sharing options...
zjrog Posted October 16, 2007 Share Posted October 16, 2007 Reading through this I got an evil grin... Take one wrecked or rusted 5.2 ZJ, and swap all the pertinent parts over to the MJ! I would think a NP242 would be preferred since you are looking for AWD in a pavement pounder. Link and coil the rear, but watch your anti-squat numbers, You want it to launch but not look like its reaching for the sky. And the 5.2 could be tuned up a bit. Use both ZJ sway bars. I couldn't imagine needing anything lower than 3.73s... And if you found a 98 5.9 ZJ that was trashed, well, no replacement like displacement! Cut some cooling vents in the hood though... Just my useless opinion! Link to comment Share on other sites More sharing options...
TNT Posted October 16, 2007 Share Posted October 16, 2007 Wanting and needing are 2 different things. I want to be able to holeshot an EVO. 8) And waste him in the 1/4.... I have almost enough parts that will be left over, I'd just need another MJ... Maybe next year. :brows: Link to comment Share on other sites More sharing options...
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