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Refresh951's Hybrid Ultra Stroker Build

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Old 12-08-2012, 11:25 PM
  #46  
V2Rocket
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Originally Posted by CyCloNe!
Shawn I got a question for you, now atleast for the 2.85l engine is it nessessary to grind the crank or could you just use the new rods, larger pistons, sleeves and such? I'm not an engine builder but I'm sure the grinding is what makes the stroker portion. I ask because I'm planning on doing what you and sid have done but want to just lighten and knife the crank instead if possible.
Part of grinding the crank down is so that the rods actually fit. The Mitsubishi rod journals are a good bit smaller than the stock Porsche ones. Offset would be up to you if you wanted to use those rods.
Old 12-09-2012, 10:20 PM
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Been doing quite a bit of reading about rod/stroke ratios. Rod/Stroke ratio on the my 2.85L was 1.74 which is considered near ideal (1.75). I think the 2.85L will prove to be an incredible design for both power and reliability.

The 3.15L will have a ratio of 1.58 which is generally considered acceptable but will definitely result in greater stress on the rings and cylinder walls. Things that must be considered in a build. My 3.15L will have a stroke of 95 mm which is the max possible with an offset grind 3L crank (with the Mitsubishi rods). Should be a good case study in the extreme. Here are some interesting articles on the subject:

http://www.hondatuningmagazine.com/t...o/viewall.html

http://www.chevyhiperformance.com/te...building_tips/

http://victorylibrary.com/mopar/rod-tech-c.htm

Last edited by refresh951; 12-09-2012 at 11:53 PM.
Old 12-10-2012, 10:39 PM
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This will give me a bit more room

Old 12-10-2012, 11:33 PM
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Shawn are you changing your pistons to larger bore or plan on keeping same bore measurements?
Old 12-10-2012, 11:36 PM
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Originally Posted by refresh951
Been doing quite a bit of reading about rod/stroke ratios. Rod/Stroke ratio on the my 2.85L was 1.74 which is considered near ideal (1.75). I think the 2.85L will prove to be an incredible design for both power and reliability.

The 3.15L will have a ratio of 1.58 which is generally considered acceptable but will definitely result in greater stress on the rings and cylinder walls. Things that must be considered in a build. My 3.15L will have a stroke of 95 mm which is the max possible with an offset grind 3L crank (with the Mitsubishi rods). Should be a good case study in the extreme. Here are some interesting articles on the subject:

http://www.hondatuningmagazine.com/t...o/viewall.html

http://www.chevyhiperformance.com/te...building_tips/

http://victorylibrary.com/mopar/rod-tech-c.htm

Check out ENDYN also. Some reading material there. I mention them before somewhere on here.

Jason
Old 12-11-2012, 01:23 PM
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Originally Posted by refresh951
- Using 86 Block, dry sleeved, bored to just over 102mm, half filled (re-used)
- JE Small Block Chevy Pistons, Forged 4032
Are the pistons for 102.108mm/4.020" bore? Like these?

http://www.summitracing.com/parts/je...make/chevrolet
Old 12-11-2012, 07:26 PM
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Originally Posted by CyCloNe!
Shawn are you changing your pistons to larger bore or plan on keeping same bore measurements?
Same bore.

Originally Posted by gruhsy
Check out ENDYN also. Some reading material there. I mention them before somewhere on here.

Jason
Thanks, some nice info!

Originally Posted by V2Rocket_aka944
Are the pistons for 102.108mm/4.020" bore? Like these?

http://www.summitracing.com/parts/je...make/chevrolet
My pistons are 4.030". My pistons are similar. I initially used a basic engine calculator to choose components such as found here:

http://www.eaglerod.com
Old 12-11-2012, 10:15 PM
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Looks like my Nissan alt, one of the better mods I did. If you want it to look really nice order the factory harness connectors. They work great. I used this on both of my cars.
Old 12-12-2012, 12:16 AM
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Originally Posted by refresh951
My pistons are 4.030". My pistons are similar. I initially used a basic engine calculator to choose components such as found here:

http://www.eaglerod.com
Pretty cool calculator. I have a crank with a spun #2 that I could get ground to 85.5mm stroke (it is a bit ground down from the bearing), and with a 4.030 bore (I have found a sleeve in 4.031", is that 0.001" to account for piston ring gap?) should be ~2.81L and a 1.753:1 rod ratio...
Old 12-12-2012, 12:45 AM
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Originally Posted by URG8RB8
Looks like my Nissan alt, one of the better mods I did. If you want it to look really nice order the factory harness connectors. They work great. I used this on both of my cars.
Yep, Nissan alt. Thanks for the tip on the connectors.

Originally Posted by V2Rocket_aka944
Pretty cool calculator. I have a crank with a spun #2 that I could get ground to 85.5mm stroke (it is a bit ground down from the bearing), and with a 4.030 bore (I have found a sleeve in 4.031", is that 0.001" to account for piston ring gap?) should be ~2.81L and a 1.753:1 rod ratio...
Both Sid and I used .0055-.0060 clearance. See below:

https://rennlist.com/forums/9439454-post6.html
Old 12-12-2012, 12:56 AM
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Originally Posted by refresh951
Same bore.



Thanks, some nice info!



My pistons are 4.030". My pistons are similar. I initially used a basic engine calculator to choose components such as found here:

http://www.eaglerod.com
Shawn, what values did you put into the calculator on the site?
Old 12-12-2012, 03:14 AM
  #57  
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Originally Posted by refresh951
Yep, Nissan alt. Thanks for the tip on the connectors.



Both Sid and I used .0055-.0060 clearance. See below:

https://rennlist.com/forums/9439454-post6.html
The battery cables the VA 'listers were making had an option that I believe included the correct connector for the quest alternator. Very nice cables if you haven't upgraded yours yet it would definitely be worthwhile looking into.
Old 12-12-2012, 03:44 AM
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I have Iceshark harnesses on both cars, but did not include the Nissan connectors. The connectors were cheap, part number and price is listed in the "How To" write up. Robbie still makes the entire Iceshark harness, including the optional lighting harness for true European fog/driving light setups. I have yet to install all of the lights but I am sure they will be blinding just by the wattages. Thus the alternator mod. The added space was a giant plus!
Old 12-12-2012, 06:45 AM
  #59  
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^^btw, did you ever get your car in the Sig dyno'd?
Old 12-12-2012, 08:14 AM
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Patrick: That is a very long and disappointing story. Car has been in Oklahoma for nearly three years now! Finally back to LR this morning, maybe will have something soon. Don't really want to say much about this nightmare. I will post results once completed.


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