Stroker

[RED_AWD_BLUR]

http://www.powderblastco.com/ 2.4

http://www.magnusmotorsports.com/ 2.4

http://www.ffwdconnection.com/ 2.3

 

[talonted_one]

uh thanks for the links but...what does that have to do with what we are talking about?

 

[RED_AWD_BLUR]

Originally posted by NosLaser
Come on Tev, I expected more than that. Enter Devil's advocate mode: Since you need to push the pin up higher with any stroker application, you begin to interfere with the oil control rings which can cause premature wear, although oiling may be slightly improved. Once you push the pin up, it usually means pushing up all three rings including the upper ring land which you really don't want too close to the heat of combustion anyway. Remedy? Taller block deck. Wouldn't that be nice. The rod stroke ratio on our cars is pretty good (roughly 1.70) and it's ideal to keep a good rod/stroke ratio on a turbocharged car. With just a custom piston and the same length rod, DISPLACEMENT ASIDE of course, you would have to run more timing to make the same power. I would think that a longer rod would be more beneficial from a rod/stroke ratio standpoint. With a longer rod, you would have more piston dwell at top dead center thus allowing more time for cylinder pressure to act on the piston, and wouldn't require as much timing to make the same power. I'm very interested in the stroker motors, just trying to see both sides of it. I'm curious as to what changes in tuning had to be made, and where the car comes on power, and if there have been any notable drawbacks to the strokers with regards to reliability, power potential on pump gas, wear and tear, etc.

Regards,

NosLaser is right increasing the rod lenght would go a long way in helping things out. Not just in dwell time but more importantly something called transmissin angle...

Transmission angle- the angle between the output link and coupler.

a.k.a. the measure of the quality of force transmission at the joint.

your trying to get this thing called your crank to turn right? this is best done by applying a force directly perpendicular to the end of the crank.
thus Force*sin(transmissionangle)*distancefromcenterofcrank=torque. the problem with this is the connecting rod pushing down on crank is NEVER perpendicular. that sucks. but the more you increase your stroke and don't increase your rod length the transmission angle shrinks. of course the trans. angle changes as the crank rotates. but this is probabbly getting boring. questions comments welcome. anyway ttyl

 

[na90dsm]

I think that was a answer for my where to get the parts question.

 

[RED_AWD_BLUR]

http://www.jepistons.com/pdf/2002-sportcompact-dodgenissan.pdf

gives good specs on stoker motors.

btw rodlength/stroke=5.906/3.937=1.50013

optimal ratio is 1.7, 1.5<<<<1.7

1.5=bad

but you are talking about more displacement.= more power. I really wish someone would dyno some engines. 2.0 vs 2.3

 

[talonted_one]

oh...Red awd blur has a very good point. now the question remains ....how can you fix the stroke ratio and rod angles. I doubt that you can but I would like to know from someone with more knowledge.

 

[talonted_one]

what will the stroke ratio be on a complete 4G64 bottom?

 

[RED_AWD_BLUR]

the (4G64) 2.4 motors supposedly have the same rod as the 4G63 right????? or are they borne w/ an inherently bad ratio?

longer rod =better transmission angles

raisdeck & use longer rod... way easier said than done

 

[talonted_one]

well from what i remember the 4g64 has the same rods as a 2g 4g63. and I believe the stroke is 6mm higher tdc and 6mm lower bdc

 

[RED_AWD_BLUR]

Sorry about the 1 sided convo. I have to update quicker.

I saw in one of my old issues of sport compact car where the machined a thick flat aluminum plate (like an xtra thick head gasket) and welded it to the aluminum block. thus the comp. ratio was lowered and the could use rods that would normally be impossible. keep in mind the rod+piston_height+stroke can only go up to about the top of the cylinder sleeve. (correctme if I am wrong). so there is only a limited amount of space. I guess it would be possible to get cylinder sleaves that were longer custom made and then all the other mods... but that is why we drive DSM's bang/$$$ otherwise we would all have twin turbo V8's

btw as rodlength goes to infinity transmission angle approaches 90 degrees thus sin(90)=1 but of course the mass of your infinitely long rod would be a little high.

 

[talonted_one]

funny ok with all that said the stroker motor has flaws ...but are they that bad of flaws?

 

[RED_AWD_BLUR]

I could stay up all night frantacally modeling w/ equations but I got to take some final exams. and it would take a LLLllllooooonnnggg time to get an aproximate anwser. I may toy with it some time. thus...

....only the dyno will tell

-Imperical data the BEST

 

[talonted_one]

you think like me ...thanks for your time and good luck with school...i wish i was there

 

[RED_AWD_BLUR]

In my personal opinoin I would definately get the 2.3 kit for the 4G63 block.

 

[RED_AWD_BLUR]

Originally posted by RED_AWD_BLUR
In my personal opinoin I would definately get the 2.3 kit for the 4G63 block.

I mean the 4G64 has been living w/ this rod/stroke ratio all its life? right? (assuming the rods are the same length) The 4G64 drops into the 4G63 block so rod/stroke ratio is the same, instalation is probabbly easier w/ less parts having to be sourced for the motor that you know fits in your car easily (4G63). but I don't know enough about the 4G64 block so I can only make a guess.

 

[talonted_one]

from what i see its basically the same just the deck height is 6mm taller, and no oil squirters.

 

[RED_AWD_BLUR]

Originally posted by talonted_one
what will the stroke ratio be on a complete 4G64 bottom?

1.5 is the rod/ stroke ratio for the 4g63 rod on a 4g64 crank

btw
where are the specs on the 4g64?

 

[talonted_one]

what specs are you looking for? alot of the info i go i read on dsmtalk

 

[RED_AWD_BLUR]

you know, if it is truly 6mm higher deck then you could use the low stroker pistons( JE,weisco,etc..) from the stroker for the 4g63 and order custom rods you could get the same cr as the pistons you ordered but get the con. rods 6mm longer than stock thus...
mm=>in is mm/25.4=inches
so 6/25.4=.23622
so orginal rod length =5.906
new rod = 5.906+.23622 =6.1422
so new rod/stroke = 6.1422/3.937= 1.56

1.56 is way better than 1.5 but still less than optimal. with a deck extender as mentioned eailier ther are probably a few more mm to be gleened. and to increse or rods length. in fact if you have enough money for custom rods you could easily afford to get someone to machine a cast iron plate and weld it to your engine. and this seems like a viable option. it would take more cash but I could eeasily see it being @ $1000 for custom rods and making/ welding a cast iron plate.

 

[na90dsm]

so would the deck plate be the only way to obtain the 6mm of extra stroke.

 

[RED_AWD_BLUR]

No the deck plate would add to that height. the 6mm comes from the supposed increased deck height of the 4G64 vs the 4G63. as long as your piston is inside the cylinder walls the plate is okay. In fact it may not have to be welded maybe 2 gaskets/ O-ringing instead? also I really would like to know were a source of the specs on the 4G64 could be found. I need this 6mm increase in deck height confirmed.

 

[RED_AWD_BLUR]

cheapest I have seen

http://monkeywrenchracing.com/mitsubishi_4g63_2_3l_stroker_kit.html

$1795

 

[na90dsm]

yea but how is there work.

 

[talonted_one]

I can refer you to various websites that will say it is 6mm higher but as far official documentation i cant find a thing.

 

[na90dsm]

anyone know of anyone on this site that could measure the 2 deck heights to prove this 6mm.