Anyone have a Renix Stroker?

[karter74]

So you guys think that if I get a set of rods from a another engine but take them to the machine shop, they will probably fit the rods to the crank?(Even if that means turning them a small amount, which I don't care about) Is this what you did, or were you lucky enough to get the rods and the crank together?

 

[Dr. Dyno]

The 258 crank & rods in my stroker came from separate sources (both from e-bay but different sellers). The crank journals had already been reground and the appropriate undersize bearings were supplied with it. The rods had also been resized, magnafluxed, and shotpeened, and they were weight-matched to within 1g. Pistons are Sealed Power 677P cast units and are weight-matched.
My stroker's just passed the 1000 mile mark and goes like $h1t on a shovel. I've taken it once up to 4750rpm and it was still pulling strong. There's a slight harmonic resonance at about 4000rpm but the engine smooths out again once past that point.

1992 XJ Laredo 4-dr - 4.6L I6 HO Stroker - 175k miles - AX15, NP231, D35c, D30
Estimated 261hp/322lbft, best 1/4 mile [email protected] before stroker install
Websites - Jeep 4.0 Performance, 4.6L Stroker Build-Up, Dino's Jeep Tricks

 

[CW]

I have an 89 stroker with an HO ported head 24# injectors and HO manifolds. It all works fine and It pulls hard all the way up to 4500 (I have never taken it past that) i went with the AP kit. After a lot of research I decided that the long rod option was best for me.

 

[Clean Racing]

Karter..

Get the rods, and the crank... take them to a machine shop. Have the crank either micro polished or turned if necessary, have the rods resized, use ARP rod bolts, and get the crank balanced and the rods match weighted.... Don't worry about what source they came from... When you get the pistons make sure the weights are within 5 grams of each other and you will be ok, no engine vibrations... To balance the 6 cyl crank does not require bobweights...pretty simple....

 

[Clean Racing]

I have an 89 stroker with an HO ported head 24# injectors and HO manifolds. It all works fine and It pulls hard all the way up to 4500 (I have never taken it past that) i went with the AP kit. After a lot of research I decided that the long rod option was best for me.

Do you have exact specs on what parts you used....I am interested in your set up... thanks for any information..

Scott.

 

[old_man]

My rig uses the early heavier 4.2L crank and stock 4.2L length rods.
Crane #750501 192/204 degree cam and springs
Ford 24lb/hr injectors with stock 39psi FPR
Block decked .025" Mopar Performance 0.043" head gasket
HP802CP .060" pistons
Renix Computer
Clifford Headers
Non-HO intake and TB.
Stock ignition.
ARB Snorkel ( actually helps highway speed power and mileage )

I've got 10k+ miles and it runs great. Runs on the cheapest gas I can buy. My only complaint was that with a stick shift, and the heavy crank, the low rpm torque allowed me to snap axles a lot easier. I have since converted to an automatic. Gets great gas mileage. Warning......this mod can get you a lot of speeding tickets.

 

[CW]

I used a '87 4.0 block
258 crank
4.0 rods
Accurate Power .030 over forged pistons
comp 250h cam
comp. lifters
HO pushrods
HO lifters
Melling high volume oil pump
hastings molly rings
HO head that I ported and pollished
91-97 intake manifold
91-97 header
HO fuel rail
ford 24# injectors
Bored HO throttle body
Relocated IAT
High altitude CPS
MAP adjuster
Air tube and cone filter
MSD 6a ignition

 

[Goatman]

I bought my motor and it already had the 24lb injectors. Now I need to replace one of them. Where is a good place to get one (or two) injectors quickly? What year or application Mustang injector do you ask for? If the price is reasonable, I can get one from work if I know what to get.

 

[old_man]

Many of the guys who built strokers picked their injectors up from ebay. Post in the wanted section. Normally you end up with 8 injectors for a 6 cylinder so you have two left over. I've got one somewhere, but God only knows where it is. From a dealer, they run about $90 each IIRC, but you can normally pick up a set that were pulled new and replaced with performance units for about $60-90 a set.

 

[Goatman]

Many of the guys who built strokers picked their injectors up from ebay. Post in the wanted section. Normally you end up with 8 injectors for a 6 cylinder so you have two left over. I've got one somewhere, but God only knows where it is. From a dealer, they run about $90 each IIRC, but you can normally pick up a set that were pulled new and replaced with performance units for about $60-90 a set.

Tom, do you know what application they are from? I have one 19lb injector and five 24lb, and I'd like to get one right away. I work at a Ford dealership, but I need to know what vehicle/motor combo those 24lb injectors come from, so I know what to ask for. On that site you linked above, I saw Mustang injectors from 19 to 24 lbs.

Thanks,

 

[Dr. Dyno]

Most of the Ford 24lb injectors are coming off Mustang Cobras and are being sold on e-bay by guys who are modding their vehicles and adding larger injectors. A lot of Mustang 65mm TB's are also sold on e-bay for the same reason. I bought one myself and I've modified it so that I can use it on my stroker. I'll post my write-up after I've done the conversion (just to make sure it works first! )
___________________________________________________________
1992 XJ Laredo 4-dr - 4.6L I6 HO Stroker - 175k miles - AX15, NP231, D35c, D30
Estimated 261hp/322lbft, best 1/4 mile [email protected] before stroker install
Websites - Jeep 4.0 Performance, 4.6L Stroker Build-Up, Dino's Jeep Tricks

 

[karter74]

Well, after much debating and talking to some local guys around here, I decided against building a stroker for now. A guy I talked to who works on Jeeps, advised that in my situation a stroker isn't something I should do right now. He said he has built 10+ stroker engines for customers but says that yes, you can build a decent budget stroker but says that the longevity of the engine is a cause for concern. He told me one they hit around 30k miles, problems start to arise and can cost money and some down time. He also said that if you run the stock computer with no re-mapping of the ignition and fuel curves, you won't be extracting the full potential for the engine and really doesn't run very efficiently. He said that if you want good, reliable horsepower, swap in a GM 4.3l V6 with the associated transmission. He said he has done this swap numerous times and said that its a great engine. He recommended to me that I just rebuild the engine to OEM specs but he said he has used the Comp cams 68-242-4 cam with great results in stock applications. I think this is what I am going to do, but I don't wanna drive an hour out of my way to take back the crankshaft I bought. Would anyone be interested in purchasing it? It came out of a newer 4.2l as it has the shorter snout on it. The crank is in excellent condition and has not been turned at all. If there are no takers, I may end up just taking it back and picking up a used stock LSD for my Dana 44.

 

[old_man]

Mine came from a Ford Mustand Cobra. Don't know the year, but if it's Bosch, just make sure the color of the injector is the same. They color code the flow rates.

 

[Goatman]

I'll have the guys at work check it out and see what they come up with. It may be more simple than I anticipate depending on the info in the parts guide......and what my price is. I also see that Jake's sells them, which is what I have since the motor came from there, so I'll give them a call on Monday too.

 

[Dr. Dyno]

Well, after much debating and talking to some local guys around here, I decided against building a stroker for now. A guy I talked to who works on Jeeps, advised that in my situation a stroker isn't something I should do right now. He said he has built 10+ stroker engines for customers but says that yes, you can build a decent budget stroker but says that the longevity of the engine is a cause for concern. He told me one they hit around 30k miles, problems start to arise and can cost money and some down time. He also said that if you run the stock computer with no re-mapping of the ignition and fuel curves, you won't be extracting the full potential for the engine and really doesn't run very efficiently.

I hope my budget stroker lasts a lot longer than 30k miles but then again, I've seen two $4600 Accurate Power long blocks go down in less than 12k miles so that's a bit worrying.
I think that if quality parts are used, the machine shop work is accurate (pun intended), the engine is carefully assembled, and the engine isn't beaten on early in its life, there's no reason why it shouldn't last at least as long as a stock rebuild.
I'd agree about remapping of the ignition and fuel curves being needed to extract the full potential of a stroker but then again you could say that about any production engine, otherwise there wouldn't be so many aftermarket chips around.

 

[Goatman]

Are there any options for improving the computer on a Renix motor, especially the '87-'88? Anyone know for sure what makes the '89-'90 motors have 27 more HP than the '87-'88's?

 

[old_man]

The horsepower is mainly from the differences in the head. The newer head has a bit more flow. I also believe that the combustion chamber is a bit smaller, yielding a higher CR. The new intake also flows better, the 2001+ even flows better. I'm not sure about the cam, but I think it changed as well. The injectors are also a bit higher flow. In all they tweaked everything a bit.

They must have tweaked the cam, because the HP is developed at a much higher rpm than the Renix motor. Better for the highway, worse for the trails.

 

[BrettM]

Are there any options for improving the computer on a Renix motor, especially the '87-'88? Anyone know for sure what makes the '89-'90 motors have 27 more HP than the '87-'88's?

I asked about that 27HP and 14 lb/ft difference and Eagle says it's a misprint: http://www.naxja.org/forum/showthread.php?t=19470

 

[Clean Racing]

Ok I don't want to be too much of a pest, but does anyone have any spec sheets from there pistons with the 4.2L crank and 4.0 rods??? Looking for pin height ect....
Thanks...

Scott

 

[Dr. Dyno]

If you use the 4.2 crank and 4.0 rods, you need custom forged pistons with a lower pin height than stock. If you don't mill the block deck, pistons with a piston pin height of 1.380" will leave the piston crowns flush with the block deck at TDC i.e. zero deck clearance.