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I have been obsessed with the idea of upgrading to a 2 liter stroker. Does anybody have a dyno for the monkey wrench stroker kit? Anybody have other recommendations for a kit? I want to build and balance it myself. Coming from the air cooled VW world where I got 207 horses out of a 1600 cc engine I would very much like to build up an engine for my Elise.
 

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No experience with that kit but would that kit make you lose max rpm? I assume that you would get lighter pistons and rods but there has to be a max piston travel speed. If you increased the distance they travel, seems like you could lose rpm. I would rather be able to spin to 9 or 10,000rpm than have more power down low. I love the close ratio trans, keeps the motor above 6k always when it is time to have fun. I feel like any amount of power below that is kind of useless except when on the road.

Increasing your redline will get you more power too as long as torque does not drop like a stone. Red-lining a 426 Hemi at 9,000 is how the drag racing guys are able make crazy N/A power out of an old school block of iron
 

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Acme Super Moderator ** The Enforcer **
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I have been obsessed with the idea of upgrading to a 2 liter stroker. Does anybody have a dyno for the monkey wrench stroker kit? Anybody have other recommendations for a kit? I want to build and balance it myself. Coming from the air cooled VW world where I got 207 horses out of a 1600 cc engine I would very much like to build up an engine for my Elise.
Not sure that's the route I'd go. Usually you give up high rpms with a stroker.

San
 
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Generally, if you stroke, you have to reduce RPM. So you'll sacrifice a bit of HP for torque.

Most people who buy that kit don't leave it as it so no dyno sheets available.

Best way to get NA power from a stroker kit would be to get 14:1 cr pistons and tune to 93 Octane gas or better.
 

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Generally, if you stroke, you have to reduce RPM. So you'll sacrifice a bit of HP for torque.

Most people who buy that kit don't leave it as it so no dyno sheets available.

Best way to get NA power from a stroker kit would be to get 14:1 cr pistons and tune to 93 Octane gas or better.
The problem with that is that even 93 octane might not be adequate. 93 in one state is crap in another. The other issue I'd have is you're only a bad tank of gas from a disaster.

San
 

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Discussion Starter #6
Must keep in mind this will still be supercharged so increased compression is not desired. High octane tunes fail as fuel consistency varies so much. Of course lightweight pistons and high strength rods would be used, give me a break. What would projectred rpm loss be? 500 to 750 rpm? Custom head porting, full balance, etc. My questions are about the quality of parts supplied in the kit. I am not familiar with thier quality. Anybody can sell a crank, but through experience I know that some suppliers use softer steel grades or have wider tolerances for quality. I am asking about quality they supply.
 

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Must keep in mind this will still be supercharged so increased compression is not desired. High octane tunes fail as fuel consistency varies so much. Of course lightweight pistons and high strength rods would be used, give me a break. What would projectred rpm loss be? 500 to 750 rpm? Custom head porting, full balance, etc. My questions are about the quality of parts supplied in the kit. I am not familiar with thier quality. Anybody can sell a crank, but through experience I know that some suppliers use softer steel grades or have wider tolerances for quality. I am asking about quality they supply.
I've had no experience with the vendor you mentioned. That said I'd look elsewhere. TurboPhil would be who I'd contact. I believe the local shop that builds the motors he uses is probably where he'd point you.

Race Solutions | Lotus Specialty and Performance Tuners

If I'm mistaken I apologize in advance.

San
 

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The stroke of the stock 1.8 is 3.35 inches, the piston must travel that distance 2 times to do 1 rotation. With a stock red line of 8,500rpm, the piston travels 17,000x3.35 inches in a minute, 56,950, which is 4745 feet/min or 53.9 miles per hour. Crazy to think that at that rpm they have to completely change direction of travel 141 times in a second!!!

What is the stroke of this kit, do you know? I was unable to find that

The 2zz's bore is 3.23, stroke 3.35

Using the formula for volume of a cylinder, pi X radius squared X height. So 3.14 x (1.615x1.615) 2.60 x 3.35 gives a cubic inch per cylinder of 27.34 or 109.39 for the whole motor or 1.78L. A liter is 61.2ci so you need a full 122.4ci. Assuming that the bore stays the same (does it??) you can only increase the stroke length and you need 30.6ci/cyl. You need a stroke of 3.75 to do that.

To make your engine spin to 8500 still, the pistons now travel 63750in/min or 60.3mph. To keep the same max piston speed you drop down to about 7500rpm.....Worth it????
 

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Except a tuned stock motor turns over 9k pretty readily, with the proper parts/precautions -- so the stroker might be fine to 8k+.

I have been interested in a 2-litre, too, but n/a. Hard to find any dyno sheets or anecdotal reports. Best source was the Newcelica forum. I was hoping for 160 rwtq. Cosworths make 175, but they are exceptional.
 

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Sorry if the 8500 was wrong, I was just using it as a figure.

Does anyone know the max shift speed of the transmission by chance?

I also wanted to add that if you were able to increase your max piston speed to that 63,750in/min but keep the stock stroke, your max rpm would jump by 1000. If the max rpm was 8500, now you have 9500. If you have a current dyno graph, draw a line with thru the current curve and follow it to 9500 to see where you could be
 

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Here's a 2 liter Coker
 

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Been there and done that... twice... wouldn't do it again... The rather small power gain is just not worth the short comings and headaches.

They do make more power. I posted about it a few years ago with dyno results. That said, I certainly do not recommend them--- especially for a car that might see track time. Seemed interesting at the time of the project but when they both expired in short order from rod bearing failure (purchased as assembled long blocks from kit maker), it was we bit alarming. :huh:

I did the tear down on both motors and saw the strategy to make it work: the piston design, rod angles, crank, spacers, bearing size, etc all a bit questionable to say the least...

Well, we live and learn;) Perhaps you can avoid the same mistakes.

Phil
 

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Discussion Starter #15
Been there and done that... twice... wouldn't do it again... The rather small power gain is just not worth the short comings and headaches.

They do make more power. I posted about it a few years ago with dyno results. That said, I certainly do not recommend them--- especially for a car that might see track time. Seemed interesting at the time of the project but when they both expired in short order from rod bearing failure (purchased as assembled long blocks from kit maker), it was we bit alarming. :huh:

I did the tear down on both motors and saw the strategy to make it work: the piston design, rod angles, crank, spacers, bearing size, etc all a bit questionable to say the least...

Well, we live and learn;) Perhaps you can avoid the same mistakes.

Phil

Thanks for the info. Was everything properly balanced?
 

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With 138mm rod length on a stock 2zz-ge engine and a stroke of 85mm, this gives a R/S ratio of about 1.62. This is a good value for a high reving engine. Once the rod angle starts to become more acute (when you stroke the engine) side loading of the piston and stress on rod bearings begin to become more of an issue. As a general rule, engines with (stock designed) long rods tend to accept being "stroked" with fewer problems. They also tend to be lower RPM motors as a design intent. Think of the 2zz-ge engine as being designed with short rods, high revving, and not generally stroker friendly. Someone may design a clever kit to overcome the challenges, but I would have to see how their longevity is before I would pull the trigger.
 

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Agreed. Not worth it.

Money is much better spent upgrading the existing motor, putting the extra you save in your pocket for a supercharger upgrade.
 

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Discussion Starter #18
Agreed. Not worth it.

Money is much better spent upgrading the existing motor, putting the extra you save in your pocket for a supercharger upgrade.
Already supercharged! I have extensive experience stroking short stroke engines. Keep in mind I used to design and build racing engines.
 

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Already supercharged! I have extensive experience stroking short stroke engines. Keep in mind I used to design and build racing engines.
Do you have a TVS/twin screw blower? If not, like I said a better blower is key.

Brush up on positive displacement blowers.

P.S. As mentioned before if you are dead set on having more cubic inch then a Honda engine would be the way to go. A k20 with basic mods would be a better engine than the MWR stroker. However it would be a lot of work in comparison to a simple build and supercharger upgrade your on your existing setup.
 

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K24 or 2GR-FE for max displacement!
 
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