RPM Machine or Speed-O-Motive Stroker Kit ?

[hmd100100]

I have a 2000 4x4 4.0L XJ sport that I mostly wheel on sand dunes. I would like to stroke the engine to a 4.6L size to gain some torque. I just need a simple stroker, nothing fancy, just crank, pistons and rods (No cam or valves …etc.). I would like to keep it as reliable as possible as it has been so far.

Let me give you some background before you ask. I don’t have hands-on experience doing mechanical work. Most of my mechanical knowledge is theoretical so I will be having a mechanic do this stoker project for me. Where I live, labor is inexpensive so he will do this for $500. And because of where I live, buying all the right parts from the U.S. will be a challenge so that’s why I was looking for a stroker kit.

I came across two kits that look O.K. I would like to see if any of you had any experience with any of them and which one would you recommend …etc.:

1. RPM Machine: “4.0L To 4.5L Jeep Stroker Kit”
http://www.rpmmachine.com/amc-stroker-kit-4l.shtml

2. Speed-O-Motive: “JEEP 4.0L TO 4.5L STROKER CRANK KIT”
http://www.speedomotive.com/ps-147-15-j ... k-kit.aspx


Thanks …….

[seanyb505]

Both probly offer the same or similar components. Call them up and see if you can get part numbers for all the parts. Whats your location?

[hmd100100]

I live in Saudi Arabia at sea level (In case that makes any difference). I'm planning to e-mail both suppliers and ask them a few questions, for example:

What is the cc of the pistons?
What's the thickness of the head gasket they assume will be used?
How much decking of the block should be done?
How much milling of the head should be done as well?

Any other questions I should ask?

I will ask about the parts numbers as well…

[seanyb505]

Yeah, ask RPM machine about the I-beam stage 1 rods they have. Are they stock reconditioned 258 rods? They probly list the CR for no block or head decking and for they stock headgasket, but it wont hurt to ask them.

[RAPTORFAN85]

Good luck with rpm machiene. I called them to try and get some spec's or even part #'s and they gave me zero help. The guy I talked to said "we don't have the specs for the parts." So, I asked for the part #'s and they couldn't even do that for me. All he could tell me was the pistons were "off the shelf pistons."
Turned me off wicked from them. They want me to buy a kit from them but can't tell me the specs or even part #'s?
don't think so...

[Alex22]

Good luck with rpm machiene. I called them to try and get some spec's or even part #'s and they gave me zero help. The guy I talked to said "we don't have the specs for the parts." So, I asked for the part #'s and they couldn't even do that for me. All he could tell me was the pistons were "off the shelf pistons."
Turned me off wicked from them. They want me to buy a kit from them but can't tell me the specs or even part #'s?
don't think so...

In all fairness its like calling up Coke and asking them for their recipe. If he told you what was in the kit then you could piece it together cheaper and not buy one from him.

I called RPM a few weeks ago about a crankshaft and they were helpful, didn't have what I wanted, but he took some time to call his suppliers and such, didn't find what I was looking for though.

~Alex

[seanyb505]

Yeah but Coke tells you how much fat, saturated fat, cholesterol, sugar etc. is in one serving size. I wouldnt put random crap in my engine.

[Cheromaniac]

I live in Saudi Arabia at sea level (In case that makes any difference). I'm planning to e-mail both suppliers and ask them a few questions, for example:

What is the cc of the pistons?
What's the thickness of the head gasket they assume will be used?
How much decking of the block should be done?
How much milling of the head should be done as well?

Any other questions I should ask?

I will ask about the parts numbers as well…

Both suppliers have what look like identical kits and the rods are indeed reconditioned 258 units.

[Alex22]

Yeah but Coke tells you how much fat, saturated fat, cholesterol, sugar etc. is in one serving size. I wouldnt put random crap in my engine.

valid point. If I was going to buy a kit I would want to know the brand of each piece in the kit so I could get an idea of the quality, but I would not expect the part numbers.

~Alex

[offroadin]

I called both RPM Machine and Speedomotive and RPM was the only ones who would talk to me. Speedomotive acted like my questions were putting them out or something. When you called RPM I think it must have been who you were talking to maybe? when I had particular questions the parts guy transfered to a guy named Dee and he not only knew exactly what parts were in the kit but gave me suggestions for 3 or 4 different ways to build my engine depending on what I wanted to get out of it and helped me with my whole kit. In the end they built me a head and put together a stroker kit combination that worked absolutely flawlessly. I would not only reccomend them but I will never have to go anywhere else for an engine part again.

[doublins]

I agree re: RPM Machine- they were immensely helpful over the phone in fielding questions about my stroker build, even though I was not buying their stroker kit. So much so, in fact, that I bought my KB 944 pistons from them rather than elsewhere simply because I WANTED to give them my business because I felt so thankful for the help they had given me in tracking down places to source a junkyard 258 crank and spending an absurdly long amount of time talking about my build w/ me. They were even willing to help me figure out how to build my head, where to source chevy valves, what machine work would need to be done, part numbers for springs, retainers, etc, and all this knowing that i wasn't ordering anything from them- they really were just paying it forward by helping me.

I would give them my business first, given other choices, simply because I want to do my part to ensure places like this stay in business.