Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 I never had a need to use the Renix sensors, but i understand that Hesco makes an adapter to use the renis sensos on a later throttle body. It is pricey at a little over $100, but i believe you only need it if you have an automatic trans. I would say that if you are going with a stroker you should go with he HO head, later intake and exhaust. You will have to move some sensors around, but i don't think this is a major problem. The Mopar Crate engine comes with a HO head. so if you use it, you will have to address the above issues. I think the crate engine is half a product. to be areal product it should come with everything you need to make it work, includng a re flashed computer. Link to comment Share on other sites More sharing options...
Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 The siren song on the mythical "budget stroker" is OOOOOHHHH so tempting. I followed the maiden for several years, doing research, doing more research, talking to people who had built strokers, talking to people who had BOUGHT strokers, and then doing more research, then crunching the numbers ... The "budget stroker" is a myth. IMHO it involves too many compromises to be a cost-effective substitute for a good rebuild. You either have too much compression, or you don't have enough. One of the solutions for the compression issue is to buy a non-stock cam with a lot of overlap, to bleed off excess compression pressure. I finally saw the light -- unless you're prepared to buy special, custom pistons to get the compression ratio correct, I think you're better off to build the engine stock, with a .030 overbore and new pistons, and then put a mild RV cam in it for more torque. Or buy a 4.2L engine, rebuild that, and throw the 4.0L head and injection on it. Things change, recently the KB944 pistons have been available for less than $400.00 per set, since they use stock 4.0 rods, the cost of the project is still reasonable and the compression ratio ends up in the low 9's A 4.2 with a 4.0 head is a real bad idea. Because of the small cylinder bore they don't breathe very well. just look at the HP numbers of a stock 258 and a stock 4.0 Link to comment Share on other sites More sharing options...
Eagle Posted November 3, 2009 Share Posted November 3, 2009 just look at the HP numbers of a stock 258 and a stock 4.0 That's not comparing apples to apples. The 4.2L never had multi-port injection, and it used an older ignition system with a rather lousy carburetor. Aside from that, the raw numbers are deceptive. It's a function of what you're looking for. The 258 didn't wind up real quick, like a short-stroke V8 engine does, but it had gobs of torque off the line and it just kept pulling all the way through the RPM range. Yes, we had a few. My brother raced a 258 Gremlin, and we had a Hornet AMX in the family for a number of years. Link to comment Share on other sites More sharing options...
Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 5.0 liters is virtually guaranteed to break through the cylinder walls. Even if it doesn't, there won't be enough metal left to dissipate heat. The only way to do a 5.0 liter stroker is to completely hog it out and then sleeve it. For all practical purposes, .060 over is the limit. Once you hit .090 over you start to worry about core shift and thin walls/heat transfer. WRONG! I built a 5.0L 4" bore, 4" stroke 13:1 cr I used a 92 WJ block which has thicked cylinder walls. The thinest part of the wall was .090 thick, this was between the cylinders. The thrust side was generally .220 or more. and the drivers side was not much less. the cylinders on the jeep motor are on about a 4.3" spacing, so if you have a 4" bore that leaves you .3" If the cylinders were touching the cylinder walls would be .150 thick per cylinder (.300 total) you do need some space for water to flow, so if the space between the cylinders is 1/8" (.125) this would leave about about enough material for a .080 cylinder wall. the outside of the cylinder is not round, it is oval, with the thin parts in the front and back of the cylinder and the thick patrts on the drivers side and the passenger side. The thin wall only exists for about 3/8" . You do have to sonic test your block to make sure it will work. The 2000+ blocks are the ones you want. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 3, 2009 Share Posted November 3, 2009 I never had a need to use the Renix sensors, but i understand that Hesco makes an adapter to use the renis sensos on a later throttle body. It is pricey at a little over $100, but i believe you only need it if you have an automatic trans. I would say that if you are going with a stroker you should go with he HO head, later intake and exhaust. You will have to move some sensors around, but i don't think this is a major problem. The Mopar Crate engine comes with a HO head. so if you use it, you will have to address the above issues. I think the crate engine is half a product. to be areal product it should come with everything you need to make it work, includng a re flashed computer. Nope, it's not half a poduct, the new Mopar crate engine is a replacement alternative for an HO engine, 91 and above. It's not designed to replace a Renix system engine and all the Renix electronics. Of course you can buy adapters from Hesco or another vendor (pricey is right) to retain certain Renix sensors, and maybe the throttle body and computer. But why? It makes better economic and practical sense to wire in an HO harness from the yard including throttle body, HO sensors, and the HO ECU. Link to comment Share on other sites More sharing options...
Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 just look at the HP numbers of a stock 258 and a stock 4.0 That's not comparing apples to apples. The 4.2L never had multi-port injection, and it used an older ignition system with a rather lousy carburetor. Aside from that, the raw numbers are deceptive. It's a function of what you're looking for. The 258 didn't wind up real quick, like a short-stroke V8 engine does, but it had gobs of torque off the line and it just kept pulling all the way through the RPM range. Yes, we had a few. My brother raced a 258 Gremlin, and we had a Hornet AMX in the family for a number of years. Maybe someone who has put the Mopar efi kit on their 258 can chime in here. The EFI does somthing but i do not believe that the 258 with efi will output more Hp than a 4.0 even though more displacment. If it did everybody would not be rebuilding their 4.0L, they would be looking for those 258s in junkyards to put their HO heads on. Link to comment Share on other sites More sharing options...
Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 Nope, it's not half a poduct, the new Mopar crate engine is a replacement alternative for an HO engine, 91 and above. It's not designed to replace a Renix system engine and all the Renix electronics. Of course you can buy adapters from Hesco or another vendor (pricey is right) to retain certain Renix sensors, and maybe the throttle body and computer. But why? It makes better economic and practical sense to wire in an HO harness from the yard including throttle body, HO sensors, and the HO ECU. So i install a engine with more displacment than stock, i think somthing has to change. At least bigger injectors. It would probably work better with a bigger than stock throttle body. Maybe a better exhaust? Stock computer will work, but maybe a modified one will work better. Sounds like you are on the ATK payroll Link to comment Share on other sites More sharing options...
dakineJ Posted November 3, 2009 Share Posted November 3, 2009 http://media.chrysler.com/newsrelease.do;jsessionid=A50907E9AD2F278511533B59A2B4AA70?mid=1&id=9219 One word: WOW! I wonder how much a crate 4.7L costs? I know what I'd like to drop into the '88 MJ 4-banger sitting out front ... 572 c.i. Hemi ? :D hornbrod , I hav'nt found the article on their website yet. If not already, you might want to pickup the last issue. Link to comment Share on other sites More sharing options...
dakineJ Posted November 3, 2009 Share Posted November 3, 2009 You do have to sonic test your block to make sure it will work. The 2000+ blocks are the ones you want. Is this just for maximum overbore?, I was under the impression that the Renix block was a stronger casting. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 3, 2009 Share Posted November 3, 2009 Nope, it's not half a poduct, the new Mopar crate engine is a replacement alternative for an HO engine, 91 and above. It's not designed to replace a Renix system engine and all the Renix electronics. Of course you can buy adapters from Hesco or another vendor (pricey is right) to retain certain Renix sensors, and maybe the throttle body and computer. But why? It makes better economic and practical sense to wire in an HO harness from the yard including throttle body, HO sensors, and the HO ECU. So i install a engine with more displacment than stock, i think somthing has to change. At least bigger injectors. It would probably work better with a bigger than stock throttle body. Maybe a better exhaust? Stock computer will work, but maybe a modified one will work better. Sounds like you are on the ATK payroll Who said that! I don't post a lot of stroker info here, and I'm not on the ATK payroll (be nice to be though :D ). Of course many improvements over stock have to change. I run a Hesco 4.6L crate motor (NOT ATK) w. a few mods, including injectors, throttle body, headers, intake, exhaust system, intake, and a Unichip to mod the stock OBDI ECU. This is all on detailed on the strokers forum w. progressive dyno results. I've followed your WFC build there w. your the projected dyno results. Unless I missed it, haven't seen any proof mate. Link to comment Share on other sites More sharing options...
Worlds Fastest Comanche Posted November 3, 2009 Share Posted November 3, 2009 We had some problems with the oil system on the engine, so I did not post any dyno numbers. The problems with the motor were posted on the stroker site, so I am not hiding anything. I stand by my statment that the MOPAR stroker is half a product. To get maximum performance out of it you will have to change and add stuff. Most of the Comanches built were Renix EFI. It is not easy to find a ODB1 Comanche. So if you want a HO head on your pre 91 comanche ( stroker or not) you really have 3 choices. 1. Keep the Renix, go with a later intake and throttle body. if you have an automatic you may need to buy the TPS adapter from hesco. For a stick vehicle the later tps should work. You will have to use the renix sensors, i think their could be an issue on the later head with one of the temp sensors, doesn't seem like a big deal. The exhaust manifold will work, but you may want to go to an aftermarket exhaust for better flow. 2. Pull the wiring harness computer and gauges out of a later model cherokee or maybe a ODB1 Comanche and rewire the truck. If you have an automatic you will need a TCU ( transmission control unit) from the later vehicle. I have stick vehicles, so I am not sure of the compatibility of the different TCUs to the different vintage transmissions. 3. Buy the ODB2 wiring harness from Hesco, I think it is about $500.00 This is the same harness used on the MPI conversion kit. Not sure of the support for the auto trans. In all cases you will need a new intake and trottle body, maybe a throttle cable or two, a stroker will need bigger injectors. Seems like keeping the Renix would be the cheaper and eaiser way to go. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 3, 2009 Share Posted November 3, 2009 Specs and price on the Mopar/ATK stroker HERE (From ATK) From Chrysler it's $4690.00 and the part number is P5155210. A $1,896 markup over ATK's price for dealer support I guess. :eek: Link to comment Share on other sites More sharing options...
WahooSteeler Posted November 3, 2009 Share Posted November 3, 2009 I couldn't believe it when someone said from Mopar it was under $3k, $4800 is what I would have expected for a dealer price. Don, IYO is the ATK price a good value? From what I remember of what you have in yours and other numbers I've seen from people, it seems like it is. Did everyone notice the higher HP/Torque ratings on the ATK site over the Mopar site? Link to comment Share on other sites More sharing options...
dakineJ Posted November 3, 2009 Share Posted November 3, 2009 There is a DIY mod for the Renix TPS. Would the other Renix sensors work with a 7120 head and a 99+ intake/throttle body? Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 3, 2009 Share Posted November 3, 2009 I couldn't believe it when someone said from Mopar it was under $3k, $4800 is what I would have expected for a dealer price. Don, IYO is the ATK price a good value? From what I remember of what you have in yours and other numbers I've seen from people, it seems like it is. Did everyone notice the higher HP/Torque ratings on the ATK site over the Mopar site? Yes, that is a damn good price for the ATK stroker. But I know nothing about these engines, and there isn't a whole lot of info on them in the Strokers forum either. The Golen and Titan strokers (about the same price) however have a lot of info there, mostly bad. Not because I have one, but you seldom see any bad feedback on the Hesco motors, except how expensive they are. Guess it's like anything else - you get what you pay for. :D Link to comment Share on other sites More sharing options...
WahooSteeler Posted November 3, 2009 Share Posted November 3, 2009 I couldn't believe it when someone said from Mopar it was under $3k, $4800 is what I would have expected for a dealer price. Don, IYO is the ATK price a good value? From what I remember of what you have in yours and other numbers I've seen from people, it seems like it is. Did everyone notice the higher HP/Torque ratings on the ATK site over the Mopar site? Yes, that is a damn good price for the ATK stroker. But I know nothing about these engines, and there isn't a whole lot of info on them in the Strokers forum either. The Golen and Titan strokers (about the same price) however have a lot of info there, mostly bad. Not because I have one, but you seldom see any bad feedback on the Hesco motors, except how expensive they are. Guess it's like anything else - you get what you pay for. :D Well, even though Mopar says upfront that they are built by ATK, Mopar still has it's name on it so you have to assume they have done some testing to feel confident about outsourcing it to ATK. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 3, 2009 Share Posted November 3, 2009 Well, even though Mopar says upfront that they are built by ATK, Mopar still has it's name on it so you have to assume they have done some testing to feel confident about outsourcing it to ATK. Yeah, you would think so Wahoo. They have been around a long time. http://atkvege.com/content/index.php/spanish/Baja-1000-win.php Link to comment Share on other sites More sharing options...
dakineJ Posted November 4, 2009 Share Posted November 4, 2009 ATK is also a major sponser of Jeepspeed. Link to comment Share on other sites More sharing options...
Blue XJ Posted November 4, 2009 Share Posted November 4, 2009 There is a DIY mod for the Renix TPS. Would the other Renix sensors work with a 7120 head and a 99+ intake/throttle body? Yes, it would work. I am running a 95 block and manifolds with a 7120 head in my Renix era jeep. I made my own adapter for the TPS and EVERYTHING else just plugged right in. I agree with the above as well, there is no budget stroker. I spent $1200 just on machine work for my block and head on mine. I think I have just under $3k into my stroker, I kind of stopped counting once it hit 2k. :dunno: Link to comment Share on other sites More sharing options...
Paul Bruchal Posted February 21, 2011 Share Posted February 21, 2011 The siren song on the mythical "budget stroker" is OOOOOHHHH so tempting. I followed the maiden for several years, doing research, doing more research, talking to people who had built strokers, talking to people who had BOUGHT strokers, and then doing more research, then crunching the numbers ... The "budget stroker" is a myth. IMHO it involves too many compromises to be a cost-effective substitute for a good rebuild. You either have too much compression, or you don't have enough. One of the solutions for the compression issue is to buy a non-stock cam with a lot of overlap, to bleed off excess compression pressure. I finally saw the light -- unless you're prepared to buy special, custom pistons to get the compression ratio correct, I think you're better off to build the engine stock, with a .030 overbore and new pistons, and then put a mild RV cam in it for more torque. Or buy a 4.2L engine, rebuild that, and throw the 4.0L head and injection on it. "Or buy a 4.2L engine, rebuild that, and throw the 4.0L head and injection on it." What would that do? The Mitsubishi Eclipse is all I know about engines the 4G63 and the 420A. I'm really wondering on this one. Link to comment Share on other sites More sharing options...
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