Stroker engine questions.
#1
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To start, I'm currently in Afghanistan. I only have you guys as a Miata lifeline. What has been on my mind lately is my upcoming engine build. Yes I searched but all the discussions end up side tracked.
First my goals. (Click on my link for more info) I want to build the engine to take full advantage of the 3071 and 750cc injectors. I am thinking boost limited to 18psi to keep the engine living for a while. The transmission will end up 6 speed.
Now, the question is whether to stroke the engine to 2.0. My hope is to be above the 350hp range, it may require a 2.0 to reach this with my above goals. Based on parts that I already have; would the stroker be worth the extra cash? I am not so sure. Do I want one? Hell yes.
Flyin` Miata stroker kit $4999
Maruha 2.1 L Stroker Kit $5300
First my goals. (Click on my link for more info) I want to build the engine to take full advantage of the 3071 and 750cc injectors. I am thinking boost limited to 18psi to keep the engine living for a while. The transmission will end up 6 speed.
Now, the question is whether to stroke the engine to 2.0. My hope is to be above the 350hp range, it may require a 2.0 to reach this with my above goals. Based on parts that I already have; would the stroker be worth the extra cash? I am not so sure. Do I want one? Hell yes.
Flyin` Miata stroker kit $4999
Maruha 2.1 L Stroker Kit $5300
#2
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To make that kind of safe power, you should be thinking about some good internal parts whether you stroke the engine or not. Stroking the motor will be more expensive, and you will have much more into it than the cost of the kit. You can never beat more cubic inches, however the biggest question you have to ask yourself is if it is in your budget.
Add up all the costs that will be associated with the build, and then come up with a budget you can afford. Eliminate the upgrades you can not afford but you can live without, and wallah, you have yourself an engine.
Add up all the costs that will be associated with the build, and then come up with a budget you can afford. Eliminate the upgrades you can not afford but you can live without, and wallah, you have yourself an engine.
#4
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I considered a V8 swap before buying the turbo but being in the Army I dont have the time for the car to sit on jacks for weeks. So without getting side tracked.
When build time comes the engine will be filled with high quality parts, just not sure about the stroker. That one dicision changes the build price about $2500.
I guess what I am kicking around is the idea of balanced parts. If the compressor is only good for X amout of flow and the injectors are only good for X amount of fuel will the stroker get me in the sweet spot or over < X. I have a map of my compressor that is plotted for a 2.0 at 2 bar. It looks to be far over to the right and high.
Damn I feel lazy asking this but the only internet I have is my work computer that I share with 6 coworkers. I am going to search for injector sizing and try to figure out what my compressor will support.
When build time comes the engine will be filled with high quality parts, just not sure about the stroker. That one dicision changes the build price about $2500.
I guess what I am kicking around is the idea of balanced parts. If the compressor is only good for X amout of flow and the injectors are only good for X amount of fuel will the stroker get me in the sweet spot or over < X. I have a map of my compressor that is plotted for a 2.0 at 2 bar. It looks to be far over to the right and high.
Damn I feel lazy asking this but the only internet I have is my work computer that I share with 6 coworkers. I am going to search for injector sizing and try to figure out what my compressor will support.
#7
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Also, like Sav said. It would be easier to reach my power levels with a larger engine.
So, after digging around some other sites I see that my 750 injectors will support up to 400 with the right pressure. So I don’t need to worry about those. I also looked at the Garrett site to see what my turbo would support but I don’t know what trim it came with. I e-mailed FM to ask them what trim my turbo was sent with.
More later.
#9
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No, you don't need a stroker. GT3071+built nonstroked motor is a combination that has been successfully executed on the miata many times. Stroker will spool faster, make moar power everywhere, but seriously, unless you're rich, don't waste your money. If I had to spend that extra $2500 on my car I would spend it on... a brand new factory hardtop!
#11
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The engine is what is on my list when I get back from hell. I see some here have 1.9 on their signature info. How are you getting 1.9? Bore?
#12
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How noticeable is this difference?
I’ve been thinking for a long time if a stroker kit is really worth it when having a big turbo like the 3071. The difference in displacement sounds quite small. The FM Stroker kit increases displacement about 8.4% and the overbore pistons increase displacement too but not that much.
I’ve been thinking for a long time if a stroker kit is really worth it when having a big turbo like the 3071. The difference in displacement sounds quite small. The FM Stroker kit increases displacement about 8.4% and the overbore pistons increase displacement too but not that much.
#15
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If you want to read the parts list of somebody who is putting down 350whp+, here's one:
https://www.miataturbo.net/forum/t11340/ That is CEO. He's for real. And he has a 2.0 stroker.
https://www.miataturbo.net/forum/t11340/ That is CEO. He's for real. And he has a 2.0 stroker.
#16
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would the stroker be worth the extra cash? I am not so sure. Do I want one? Hell yes.
#17
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I know MRM is working on a less expensive 2.0 stroker solution. The rumor is someone local will be running one soon.
McCully Racing Motors- There's no Replacement for Displacement.
McCully Racing Motors- There's no Replacement for Displacement.
#18
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AFCO's already done. I have the torsen now but the 4.30's are killing me. 1st is gone in a heart beat. A MS rear with 3.90's and a 6 speed is on my list of to do's. FM anti-sway bars will be here soon. Brakes and wheels? Done.
The engine is what is on my list when I get back from hell. I see some here have 1.9 on their signature info. How are you getting 1.9? Bore?
The engine is what is on my list when I get back from hell. I see some here have 1.9 on their signature info. How are you getting 1.9? Bore?
Yup 1929cc with an overbore here too.
#20
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The GT3071R that FM specs is a 0.63 A/R, IIRC.
I'm running FM's stroker motor with 750 cc/min injectors and this turbo. It's a sweet combination, with low-end grunt with an addictive mid-range. Top end maxes out at about 7,500 rpm, but unless I change the cams and perhaps the intake manifold, I'll have to live with it![Stick Out Tongue](https://www.miataturbo.net/images/smilies/tongue.gif)
Regarding fueling: Even at 400+ rwhp, I still had lots of injector capacity left.
If you're going to spring for a stroker, my advice is to go with the FM kit. It's been tested to ludicrous power levels (550-800 rwhp) and, more importantly, the rod ratio (when coupled with their rods/pistons) is kept stock for "revability". The MRM kit appears to get the displacement only through increased bore, so you won't get the low-end torque a stroker affords.
Have fun - I know I do.
I'm running FM's stroker motor with 750 cc/min injectors and this turbo. It's a sweet combination, with low-end grunt with an addictive mid-range. Top end maxes out at about 7,500 rpm, but unless I change the cams and perhaps the intake manifold, I'll have to live with it
![Stick Out Tongue](https://www.miataturbo.net/images/smilies/tongue.gif)
Regarding fueling: Even at 400+ rwhp, I still had lots of injector capacity left.
If you're going to spring for a stroker, my advice is to go with the FM kit. It's been tested to ludicrous power levels (550-800 rwhp) and, more importantly, the rod ratio (when coupled with their rods/pistons) is kept stock for "revability". The MRM kit appears to get the displacement only through increased bore, so you won't get the low-end torque a stroker affords.
Have fun - I know I do.