Jump to content

Stroker porn


Recommended Posts

Now that my subject line got "asses in the seats"

 

Been gathering parts to build 3 strokers...last week had a good soild 3727 (90 4.2) shipped from out west

 

Yesterday....a farm find.....the white wale......the mythical 4723......no need to go into the specs....a picture is worth a thousand words...

 

 

Maybe it is just me....but it is the first one i have ever seen......without listing the specs....can you see the difference and benefits?

 

. :MJ 1: .  :banana:

Link to comment
Share on other sites

The one on the left has much less mass meaning it'll rev more happily and be better suited for high-revving, high-hp applications.

The one on the right has much more mass and will make for a better low-end-torquey workhorse engine.

Link to comment
Share on other sites

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal..... . :MJ 1: .

Link to comment
Share on other sites

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal..... . :MJ 1: .

Possibly. He's got more dyno time on 4.6 strokers than anyone in the country. What would he know? 

Link to comment
Share on other sites

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal..... . :MJ 1: .

 

That is the problem with bench racing and the butt dyno.  No real difference, but it just "feels" better.  Placebo effect.

 

When I get home, I will take a real "stroker porn" picture and see about posting it.  A Jeep 4.095 stroke crankshaft.  Good for an extra 14 cubic inches on any stroker.  Up to a full 5.0 if you like.

Link to comment
Share on other sites

Well like I said I am building 3 Strokers....the crank above on the left is a 4 weight 3727 casting so I will not have to speculate on differences I will be able to compare them side by side...

But research....logic and experiance tell me this...

The 12 weight 4723 casting is a stronger crank that will offer me more low end/rpm torque...and (when touched by an installer who is knowledgeable) will give me a smoother running more balanced finished product.... If Chad or anyone else has a different opionion.....good on 'em 'eh   . :MJ 1: .  

Link to comment
Share on other sites

For warm fuzzies when you hit the go-go pedal, I don't expect you'll notice a significant difference between the two. But I think it'll be opposite of what you expect, the lighter crank would give better acceleration with less mass to get moving.

Link to comment
Share on other sites

 

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal..... . :MJ 1: .

Possibly. He's got more dyno time on 4.6 strokers than anyone in the country. What would he know?

 

I think Lee Hurley at Hesco has built and dynoed a few more than the above. 

Link to comment
Share on other sites

For warm fuzzies when you hit the go-go pedal, I don't expect you'll notice a significant difference between the two. But I think it'll be opposite of what you expect, the lighter crank would give better acceleration with less mass to get moving.

Your assuming I am seeking drag strip acceleration to get my warm fuzzy fix....I will be happier with that long strong pull that I will get on the road in 5th with a load or pulling a trailer... . :MJ 1: .

Link to comment
Share on other sites

Wouldn't an extra heavy flywheel do exactly the same thing?  Just a question

 

Are you building all three strokers exactly the same?  What cam are you using for best low end?  I kind of think the stock Renix era cam set for 8 degree retarded is the best I have seen for low end torque.

Link to comment
Share on other sites

They use weighted fly wheels on jeep 4 bangers and on RX rotary mills so the same theory applies.

 

As for the second question....I might ....

The first will be a 2000 XJ block/intake/exhaust with a 1995 YJ ho head and the 12 weight crank.....cam and pistons both have a list (but not a decision) so far...

 

. :MJ 1: .

Link to comment
Share on other sites

4-bangers aren't typically very well balanced so the extra weight contributes to smoothness. The Wankel is a completely different animal, but not a very torquey motor, needs the pants revved off it to make power.

They also sell light-weight flywheels for racing applications, because less rotating mass makes for better acceleration.

 

I haven't been around that long, so I won't profess to know everything. We can speculate all we want, but we'll have to wait till you've got it done to find out. I'm curious either way... either I'll have confirmed my hypothesis, or I'll learn something new. Just have to wait and see.

Link to comment
Share on other sites

Actually they market add on weights to the 4 bangers to do the exact same thing the 12 weight will do...keep the mass rotating at a low RPM....helps in tight slow crawling situations.....The rotary add on gives the boys the rotating mass they don't have but want.

Link to comment
Share on other sites

I feel real special now cause I've got two 12cw cranks in my garage just waiting to be used. :D

 

Didn't know they had achieved mythical status.

 

 

BIG question, whats the deal with this crank spacer I keep hearing about?

 

What connecting rod/piston combo is going to be used? What about injectors and fuel management?

Link to comment
Share on other sites

Yup, the 12 weight crank needs a 10mm spacer to tighten the balancer on all the way.  Or you can have whatever shop does the crank take 10mm off the snout. 

 

As for the benefit of the heavy crank, it depends on your transmission.  With an auto, you won't be able to tell the difference, and there really is no benefit. 

With a manual, it'll be better equipped to idle over things without stalling with the heavier crank, and it'll also smooth out the power delivery at low RPM's.  Heavier flywheels do the same thing, which is to smooth out the low speed torque delivery by being a giant mass damper. 

From a seat of the pants performance perspective (0-60mph), or even dyno hp and torque, there is pretty much zero difference. 

 

I'm hoping to start a stroker project too soon for my TJ.  (2003 engine in a '98) I have two 12 weight cranks to choose from, and I'll be getting rid of the 0331 head in favor of either a 0630 or 7120 for better exhaust flow.  Aside from hearing that everyone loved the Mopar purple cam, I can't find much good on aftermarket cams.  Lots of guys saying the higher lift cams don't last because the lobes are narrow and we have no zinc in oil anymore.  Plus most of them require different valve springs and keepers, plus machining on the head to use it depending on which ones you go with...   I've read many places that for a daily driver/trail rig, you may as well keep the stock cam, and just advance it 4°.   Because I have a newer engine, there is no cam pin to drill out for an offset bushing, so my only solution is an offset crank key, which can provide 4° at the crank, but that's only a 2° cam timing change.  :(     Well, 2° is better than nothing, so that what my Jeep is getting.  

 

And you advance the cam for low end torque, you retard it for HP. :)

And 8° of advance is a LOT.  The most I've seen suggested was 4°.   (Aside from a very misleading thread on Jeep Strokers that was actually talking about a simulation program, not the real world...)

 

I already have new Silvolite Hypereutectic pistons, as there were piston skirt failures in some of the later 4.0's, or I'd have re-used the stock pistons.  

 

You use the 258 rods if you want to go that route.   If you want to spend big $$, then you can buy special pistons and use the longer 4.0L rods, but you don't gain that much on a daily driver, aside from a lower compression ratio allowing regular gas. 

 

SBEC engines at low elevation like a little fuel pressure increase, JTEC engines seem to do fine without at all elevations.   At altitude, you don't even have to mess with fuel pressure on SBEC.  You'll probably have to run mid-grade lower than ~6k feet because of the bump in CR.  Above 6k, you'll probably be fine, even on regular.  

 

Keep us posted!!

Chris

Link to comment
Share on other sites

Yup, the 12 weight crank needs a 10mm spacer to tighten the balancer on all the way.  Or you can have whatever shop does the crank take 10mm off the snout. 

 

As for the benefit of the heavy crank, it depends on your transmission.  With an auto, you won't be able to tell the difference, and there really is no benefit. 

With a manual, it'll be better equipped to idle over things without stalling with the heavier crank, and it'll also smooth out the power delivery at low RPM's.  Heavier flywheels do the same thing, which is to smooth out the low speed torque delivery by being a giant mass damper. 

From a seat of the pants performance perspective (0-60mph), or even dyno hp and torque, there is pretty much zero difference. 

 

I'm hoping to start a stroker project too soon for my TJ.  (2003 engine in a '98) I have two 12 weight cranks to choose from, and I'll be getting rid of the 0331 head in favor of either a 0630 or 7120 for better exhaust flow.  Aside from hearing that everyone loved the Mopar purple cam, I can't find much good on aftermarket cams.  Lots of guys saying the higher lift cams don't last because the lobes are narrow and we have no zinc in oil anymore.  Plus most of them require different valve springs and keepers, plus machining on the head to use it depending on which ones you go with...   I've read many places that for a daily driver/trail rig, you may as well keep the stock cam, and just advance it 4°.   Because I have a newer engine, there is no cam pin to drill out for an offset bushing, so my only solution is an offset crank key, which can provide 4° at the crank, but that's only a 2° cam timing change.  :(     Well, 2° is better than nothing, so that what my Jeep is getting.  

 

And you advance the cam for low end torque, you retard it for HP. :)

And 8° of advance is a LOT.  The most I've seen suggested was 4°.   (Aside from a very misleading thread on Jeep Strokers that was actually talking about a simulation program, not the real world...)

 

I already have new Silvolite Hypereutectic pistons, as there were piston skirt failures in some of the later 4.0's, or I'd have re-used the stock pistons.  

 

You use the 258 rods if you want to go that route.   If you want to spend big $$, then you can buy special pistons and use the longer 4.0L rods, but you don't gain that much on a daily driver, aside from a lower compression ratio allowing regular gas. 

 

SBEC engines at low elevation like a little fuel pressure increase, JTEC engines seem to do fine without at all elevations.   At altitude, you don't even have to mess with fuel pressure on SBEC.  You'll probably have to run mid-grade lower than ~6k feet because of the bump in CR.  Above 6k, you'll probably be fine, even on regular.  

 

Keep us posted!!

Chris

Well stated.

Link to comment
Share on other sites

 

 

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal..... . :MJ 1: .

Possibly. He's got more dyno time on 4.6 strokers than anyone in the country. What would he know?

 

I think Lee Hurley at Hesco has built and dynoed a few more than the above. 

 

That's also possible. Which crank does he prefer? 

Link to comment
Share on other sites

 

Never asked him. :dunno:

Probably no need to.

We seem to now have a self proclaimed stroker expert now anyway.

 

:yes:   For stroker matters I only listen to people who have a running stroker with dyno results.

Link to comment
Share on other sites

Hornbrod....what crank was used in the 4.6 you are putting your foot into daily?

 

The Hesco kits I was able to see all had the 4 weight...is that their standard?

 

I personally never put Dyno on my list of things to do...2 of the motors are going in Jeeps that I have owend and driven for years...any performance gains or loses will be easy to judge.

Link to comment
Share on other sites

Hornbrod....what crank was used in the 4.6 you are putting your foot into daily?

 

The Hesco kits I was able to see all had the 4 weight...is that their standard?

 

I personally never put Dyno on my list of things to do...2 of the motors are going in Jeeps that I have owend and driven for years...any performance gains or loses will be easy to judge.

Whoa, whoa, whoa. You're gonna use a butt dyno and bench race this stuff? 

 

Your quote below:

 

 

Well good on Chad....but me thinks all those extra counter weights flailing around in my oil pan as I cruz down the highway will give me a warm fuzzy feeling inside every time I push down on the go-go pedal.....

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...