Which stroker is best?

[Zack Huffman]

I'm late to the party but thought I'd throw something in here since there's so much discussion on what parts are needed for each engine.

The practical limit in bore size is 88mm, or 0.060" overbore for a 2.4L(very risky and usually only done on 2.4L blocks).

The formula for displacement is 3.1415 * (bore/2)^2 * stroke * number of cylinders.
(Rod ratio is simply rod length divided by crank stroke.)


Using an 88mm (stock 2.0L) crankshaft:

85mm bore = 1997cc
85.5mm bore = 2021
86mm bore = 2045
86.5mm bore = 2068
87mm bore = 2092
87.5mm bore = 2116
88mm bore = 2141

Rod Ratios:
All are off the shelf parts

stock piston and 150mm rod = 1.70​

stroker piston and 156mm rod = 1.77​

stroker piston, 2.4 block, 162mm rod = 1.84​

For a 92mm Magnus crankshaft:

85mm bore = 2088cc
85.5mm bore = 2113
86mm bore = 2138
86.5mm bore = 2163
87mm bore = 2188
87.5mm bore = 2213
88mm bore = 2238

Rod Ratios:

Custom Rod Length​

stock piston, 148mm rod = 1.61​

stroker piston, 154mm rod = 1.67​

stroker piston, 2.4 block, 160mm rod = 1.74​

Custom Piston Compression Height​

150mm rod, 33mm CH piston, 2L block = 1.63​

150mm rod, 39mm CH piston, 2.4L block = 1.63​

156mm rod, 27mm CH piston, 2L block = 1.69​

156mm rod, 33mm CH piston, 2.4L block = 1.69​

162mm rod, 27mm CH piston, 2.4L block = 1.76​

For a 93mm 4D68 crankshaft:

85mm bore = 2110cc
85.5mm bore = 2135
86mm bore = 2160
86.5mm bore = 2186
87mm bore = 2211
87.5mm bore = 2236
88mm bore = 2262

Rod Ratios:

Custom Rod Length​

stock piston, 147.5mm rod = 1.586​

stroker piston, 153.5mm rod = 1.650​

stroker piston, 2.4 block, 159.5mm rod = 1.715​

Custom Piston Compression Height​

150mm rod, 32.5mm CH piston, 2L block = 1.61​

150mm rod, 38.5mm CH piston, 2.4L block = 1.61​

156mm rod, 26.5mm CH piston, 2L block = 1.67​

156mm rod, 32.5mm CH piston, 2.4L block = 1.67​

162mm rod, 26.5mm CH piston, 2.4L block = 1.74​

For a 94mm Eagle crankshaft:

85mm bore = 2134cc
85.5mm bore = 2159
86mm bore = 2184
86.5mm bore = 2209
87mm bore = 2235
87.5mm bore = 2261
88mm bore = 2287

Rod Ratios:

Custom Rod Length​

stock piston, 147mm rod = 1.56​

stroker piston, 153mm rod = 1.63​

stroker piston, 2.4 block, 159mm rod = 1.69​

Custom Piston Compression Height​

150mm rod, 32mm CH piston, 2L block = 1.59​

150mm rod, 38mm CH piston, 2.4L block = 1.59​

156mm rod, 26mm CH piston, 2L block = 1.659​

156mm rod, 32mm CH piston, 2.4L block = 1.659​

162mm rod, 26mm CH piston, 2.4L block = 1.72​

For a 97mm Crower crankshaft:

85mm bore = 2202cc
85.5mm bore = 2228
86mm bore = 2254
86.5mm bore = 2280
87mm bore = 2306
87.5mm bore = 2333
88mm bore = 2360

Rod Ratios:

Custom Rod Length​

stock piston, 145.5mm rod = 1.5​

stroker piston, 151.5mm rod = 1.56​

stroker piston, 2.4 block, 157.5mm rod = 1.62​

Custom Piston Compression Height​

150mm rod, 30.5mm CH piston, 2L block = 1.54​

150mm rod, 36.5mm CH piston, 2.4L block = 1.54​

156mm rod, 24.5mm CH piston, 2L block = 1.60​

156mm rod, 30.5mm CH piston, 2.4L block = 1.60​

162mm rod, 24.5mm CH piston, 2.4L block = 1.67​

For a 100mm (stock 2.4L) crankshaft:

85mm bore = 2270cc
85.5mm bore = 2296
86mm bore = 2323
86.5mm bore = 2350
87mm bore = 2378
87.5mm bore = 2405
88mm bore = 2433

Rod Ratios:

stock pistons, 144mm rod = 1.44​

stroker pistons, 150mm rod = 1.50​

stroker pistons, 2.4 block, 156mm rod = 1.56​

For a 102mm Crower crankshaft:

85mm bore = 2315cc
85.5mm bore = 2342
86mm bore = 2370
86.5mm bore = 2397
87mm bore = 2425
87.5mm bore = 2453
88mm bore = 2481

Rod Ratios:

Custom Rod Length​

stock piston, 143mm rod = 1.40​

stroker piston, 149mm rod = 1.46​

stroker piston, 2.4 block, 155mm rod = 1.52​

Custom Piston Compression Height​

150mm rod, 28mm CH piston, 2.0L block = 1.47​

150mm rod, 34mm CH piston, 2.4L block = 1.47​

156mm rod, 28mm CH piston, 2.4L block = 1.529​

For a 106mm Crower crankshaft:

Crower states the 106mm crank must be used in a 2.4L block, stock 2.4L bore is 86.5mm.​

85mm bore = n/a
85.5mm bore = n/a
86mm bore = n/a
86.5mm bore = 2491cc
87mm bore = 2520
87.5mm bore = 2549
88mm bore = 2579

Rod Ratios:

Custom Rod Length​

stock piston, 2.4 block, 147mm rod = 1.39​

stroker piston, 2.4 block, 153mm rod = 1.44​

Custom Piston Compression Height​

150mm rod, 32mm CH piston, 2.4L block = 1.41​

156mm rod, 26mm CH piston, 2.4L block = 1.47​

These are all of the crankshaft stroke lengths I have ever heard of anyone actually using. There are probably some other custom length ones out there (Japanese made), but most of those are pricey and unproven. If I've forgotten any, I'll edit this post as I'm made aware of them.

For reference the 2.4 blocks have a deck height of 235mm and the 2.0 blocks have a deck height of 229mm. The compression heights for the custom pistons I listed are based on zero deck, slightly taller heights can possibly be used if the pistons are carefully designed, a thick head gasket is used and/or a higher compression ratio is desired.

If I had an unlimited budget for a race only car I'd probably build a 2.2L. If I had an unlimited budget for a road going car, I'd build a long rod 2.4L. For anything else, or on my actual budget, I'd build a 2.3L.

 

[v8s_are_slow]

Good info getting posted up. Think I'm personally going with the 2.3 I was already thinkin about I guess. Now if only I can figure out if aluminum rods will work in it or not. Probably end up clearancing so much that I'd have to go right through the girdle. Lol.

 

[autotalon]

That is an excellent post, Delta. I vote this thread gets stickied.

 

[dsmusmc]

I'm late to the party but thought I'd throw something in here since there's so much discussion on what parts are needed for each engine.



If I had an unlimited budget for a race only car I'd probably build a 2.2L. If I had an unlimited budget for a road going car, I'd build a long rod 2.4L. For anything else, or on my actual budget, I'd build a 2.3L.

You should update the 92mm Magnus crank with there pistons and 150mm rods is a 1.63 rod ratio.

The 2.2 stroker is a great all purpose engine. After talking with Marco before making my choice he was telling me how it would have the low end power/torque of a 2.3 yet the capability to rev like a 2.0 ("safe" limit 9.5K). It's expensive but IMO the best of both worlds.

 

[Zack Huffman]

You should update the 92mm Magnus crank with there pistons and 150mm rods is a 1.63 rod ratio.

Quoted post and above post edited to reflect custom piston choices as well as custom rod choices.

For future reference,
2.0L block = 229mm deck height
2.4L block = 235mm deck height

So, if you want to know the compression height (in millimeters) of the piston that will allow you to use X rod length with Y stroke length in a 2.4 block;

CH = 235mm - X - (0.5 * Y)

or for a 2.0L block;

CH = 229mm -X - (0.5 * Y)

You can divide that number by 25.4 to change the compression height from millimeters to inches.

 

[WES_393]

I thought the 4g64's in the galants up until 03 were ok. I've been looking for a split thrush main seven bolt to built a 2.1.

I'm not sure if the 00-03 Galant engines are DSM trans compatible. I've honestly never looked into which specific years you can use, so your word trumps mine. But I know for certain the 4g64 blocks from the 3g Eclipse and Outlander don't quite bolt up. I made the mistake of purchasing one only to find out it would require some kind of adapter plate or bell housing extension that doesn't yet exist. So the only useable part from those engines as of now is the 100mm crankshaft. Since its identical to the crank found in the DSM compatible 4g64, it too can be stuffed in a 4g63 to make a 2.3 stroker. Here's the thread on my 3rd gen 4g64 project, which is unfortunately on the back burner for now.

http://www.dsmtuners.com/forums/cylinder-head-short-block/428378-newer-4g64-2g.html

Sorry to stray off topic a bit, still relevant to the stroker discussion though.

 

[v8s_are_slow]

Just wondering but who's using balance shafts in your strokers to help with the harmonics? I took mine out in my 2.0 but wondering if it'd be worthwhile to put them back in if I stroke it, or just leave them out. If vibration inside the car is the only concern, then I wouldn't care about that. But if it helps with engine life then I probably would.

 

[blizz99]

I'm running prothane sides and avid front mounts with no balance shafts in and the vibration is wicked . Can't speak of longevity yet because I only have 200 miles on the setup. I've heard you should use a Fluidamper. I'll eventually get one for reassurance of longevity.

 

[gprix1]

I do not run balance shafts on my 2.4L and it is barely more vibration than my stock 2.0L with BS. I did have my rotating assembly balanced which probably helps with that but I can say that it is not bad at all on my car. Also, I did WindoWeld on all my mounts.

 

[gofer]

Just wondering but who's using balance shafts in your strokers to help with the harmonics? I took mine out in my 2.0 but wondering if it'd be worthwhile to put them back in if I stroke it, or just leave them out. If vibration inside the car is the only concern, then I wouldn't care about that. But if it helps with engine life then I probably would.

Jackson Auto (JAM) won't even assemble a stroker without leaving the BS's in, they actually take the time to machine/clearance the BS's because they think it's so important. Just call and ask.

On another note, the Fluidampr harmonic damper IS NOT SFI certified, the only one that is manufactured for our cars is the ATI damper. SFI certification is important if you're racing, which I assume you are if you are building a stroked 4g63.

 

[v8s_are_slow]

I guess my biggest debate with a stroker motor is the rod selection. I've planned on aluminum rods for a 2.0 for a long time. But I'll be going with a 2.3 instead, and not sure how much clearancing will be needed, or what would have to be done to make it work without destroying the main caps/girdle/whatever ya call it.

So anyway, debating on those or steel rods. Wonder what people suggest, and why. H-Beam? I-Beam? I know Buschur doesn't even offer aluminum rods on his page for a 2.3 short block. Not sure why. So has me wondering. "His" page says the shortblock comes with Manley rods. But not sure which ones.

 

[gofer]

From the desk of Dr. Zimmer regarding my personal 2.3 build...

I would strongly recommend upgrading the rod bolts to the better material, along with running the thick-wall tool steel wrist pins, they should be like .220-.240" thick depending on manufacturer, and you would need it in the 22mm flavor for diameter since you are running a 2g rod/bushing diameter. Run with wire locks also.

Be sure to clearance the block and give some extra room for thermal expansion. You will likely need to do some webbing grinding, and maybe a bit at the bottom of the cylinder wall and main oil galley. Thankfully it shouldn't take too much since you are running a small rod, if you were running aluminums I would tell you to run steel rods or get a lot of time and a good machinist to get it done properly in a 2g motor. Also, plug the oil squirters or weld them shut.

When you do run the BSEK, change the stock 2g oil pump gears to 1990 straight cut gears in the 2g oil pump case assembly and debur/detail the gears.

As well, I would strongly recommend installing a Kiggly HLA restrictor and a quality oil pressure gauge off of the oil filter housing with an isolated -4an line as the pressure sender or map sensor will last a lot longer.

Tim Zimmer via Evo Phone

I run aluminum Mitsubishi mains with ACL coated rod bearings. My old steel rod 2.3L ran Mitsubishi/clevite rod and they pounded themselves apart above the 700awhp mark where it was fine in the 600-650whp range. Personally, I would go with a soft bearing like a Mitsubishi or ACL coated bearing on a steel rod stroker, as there is a lot of thrust loading put onto the bearings. I would also only run a 15w50-20w50 oil in it. Brad Penn, Schaeffer's, Rotella T, Lubrication Engineering, or Valvoline synthetic racing high zinc (blue color oil), or CAM2 oil. All are high zinc and the Lubrication Engineering has a parrafin base which requires a bit more cooldown so it doesn't coke the bearings, but its film protection is outstanding.

I will respond more tomorrow.

Tim Zimmer via Evo Phone

I didn't shot-peen my rods; but I used an H-beam design instead of an I-beam as it has shown better structural rigidity on a high rod angle motor such as the 2.3L. I simply used off-the-shelf Eagle H-beam's with no issues up to 766AWHP/713TQ on the GT4088R on a 0.94A/R divided T4 housing.

As for the butchered crank, I saw jump-roping (crank deflection/bending) when we started running above 650AWHP and 35psi of boost up to 8600rpm. Funny enough, I was running the regular thin-wall wrist pins that come with the pistons instead of the upgraded ones. If I was to do it again, I would have upgraded the rod bolts and the wrist pins to the thicker wall tool steel pins and wire locks as those things seemed to be the weakest link in the setup other than the heavily cut down crank. Currently, I am simply running a stock crank with a micropolish and that's it. No issues up to 835+AWHP and as high as 55psi boost on the 74mm BW turbo. If you are running an uncut crank, I don't think you will see an issue with crank deflection. As for bearings, the Tri-Metal's from Clevite looked like shit very quickly once the crank bent (0.015" out of straight ), and the outer bearings looked great, the inner mains and thrust was smoked, the side washers were fine though, just the main journal bearing was smoked. It was also taking out crank angle sensors when it got to this point, as well as it threw the OEM crank harmonic balancer pulley counterweight twice in a short period of time (pulley seperated).

The oil pump gears you linked are the proper straight-cut 1990 gears that I use with a Mitsu stub shaft. I did not port the oil relief. Guys on NABR discussed in the past of porting the oil drain back passsageways on the head and block to get more oil back into the pan quicker since our oil pumps are so high capacity and you would shit out a pump if you sucked air instead of oil. I always ran around 5 quarts in my motor and if I did it again, I would shroud the oil pump pickup screen like Kiggly did along with a HLA restrictor.

As for block clearancing, yes, you will require some clearancing, but nothing near the amount of an aluminum rod motor. I needed to clearance the girdle, main oil galley, block webbing, and bottoms of the cylinder walls to clear the aluminum rods as well as give extra space for thermal expansion. I also had to filers cut the rods at the big end curvature and balance the entire rotating assembly, and then the pistons and pins were custom, skirt coatings, .240" wall H11? Tool steel wrist pins, 7/16" ARP custom age fasteners, etc. I went a bit overboard. I have some pictures of this work when the block was assembled from my cell phone, however I cannot find the old pictures I took of the old engine bearings showing the jump rope effect on them, but it is self explanatory.

 

[v8s_are_slow]

Thanks. I spoke to him about it a bit but he didn't discuss everything he had to do for the clearancing. Guess I'll be sticking with the steel rods. Just not sure what the HLA thing is so guess I need to research on that.

And although I guess I'm sticking with steel rods, I just found this page for anyone who cares to read about aluminum rods....
Debunking Aluminum Rod Myths With GRP - StangTV

 

[gofer]

Kiggly Racing - kigglyracing.com

 

[JacksonAuto]

Based on feedback from our customers the debate for us has been narrowed down to this-

Street/AutoX/DD or any combination of the three = 2.3L
Strictly drag racing = 2.0L
2.1 or 2.2 = for the guy that likes to over-analyze things

We've never built a 2.3 that the customer wasn't happy with the torque/power/RPM. We have, however, had customers disatisfied with a 2.0 and built them a 2.3.

 

[Hal]

Street/AutoX/DD or any combination of the three = 2.3L
Strictly drag racing = 2.0L
2.1 or 2.2 = for the guy that likes to over-analyze things.

Perfect summary

 

[TunaTalon]

2.1 or 2.2 = for the guy that likes to over-analyze things

Not necessarily. The research of and drafting of http://www.kidzuku.com/StrokeOrNot.pdf should put me at the head of the list of over-analyzers, and clearly mark movement over to the dork side. And my Talon pulls me under fresh green lights with a 2.3L stroker.

I think the emotional appeal of the 2.1L is making the Eagle scream and feeling the rush when the big turbo spools up. Or to the 2.3 L drivers; when the power finally comes on.