strokers and CA smog?

Yea, that is true. Lawzy knows I could use more of that.

JohnX said:

Theres a reason my cummins has a 4.72" stroke.

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you're asian?

Vanimal said:

you're asian?

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Half asian, half black...it averages out.

JohnX said:

Theres a reason my cummins has a 4.72" stroke.

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Because you've always said you wanted a motor with twice the stroke you're used to?

Skwerly said:

I have considered stroking my 4.0

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Wow, have you grown an inch? I guess those pills work after all

You know, I even re-worded that to avoid such tom-foolery.

I had originally put something like, "I have considered stroking mine, but..."

You guyz iz nutz.

89 4.0 block bored 40 over with 4.0 40 over pistons
71 4.2 rods and crank (the 80 LB one)
24lb four brothers racing injectors
96 HO head
93 intake
93 Computer with NO mods
OBD2 race high flow cat
has to run on 91 octane
4.7L
Runs cleaner than stock, amazes my "California" smog guy.

Just my 2 cents
JOhn

HandBuiltXJ said:

89 4.0 block bored 40 over with 4.0 40 over pistons
71 4.2 rods and crank (the 80 LB one)
24lb four brothers racing injectors
96 HO head
93 intake
93 Computer with NO mods
OBD2 race high flow cat
has to run on 91 octane
4.7L
Runs cleaner than stock, amazes my "California" smog guy.

Just my 2 cents
JOhn

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nice, seems to be the norm for them to run cleaner than stock. i just dont want to run higher than 87 due to the cost of gas.

Vanimal said:

nice, seems to be the norm for them to run cleaner than stock. i just dont want to run higher than 87 due to the cost of gas.

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Take that into account int eh build.

Myself whenever I build up mine it'll run on premium, I can handle the extra $0.20/gal for my toy.

Chip Clip said:

By the way you can use stock rods, no need for the 4.2. I also think it is more for the crank like $200. Dont you also have to grind the front of the crank where the balancer goes on.

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You can use the stock 4.2L rods with stock 4.0 pistons.

The better way to do it would be using the stock 4.0 rods with custom 4.0 pistons with the wrist pin set closer to the piston face, this would reduce the angle of the rods while rotating and reduce piston skirt to cylinder wall contact which will eventually oval your cylinder walls.

I have about 5 or more years on my stroker and will be going the longer rod and custom piston route when i build my next one.

John

My Renix was advertised new with something like 177hp. What are realistic numbers from a mild stroker? I've always wanted to just dump a 318 in my Cherokee and be done with it, but I don't want a newer one, so it isn't possible without a green sticker.

Le sigh...

My stroker has no problem with smog. I do have to run 91 tho no big deal.

HandBuiltXJ said:

89 4.0 block bored 40 over with 4.0 40 over pistons
71 4.2 rods and crank (the 80 LB one)
24lb four brothers racing injectors
96 HO head
93 intake
93 Computer with NO mods
OBD2 race high flow cat
has to run on 91 octane
4.7L
Runs cleaner than stock, amazes my "California" smog guy.

Just my 2 cents
JOhn

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What pistons are you using. Also the 4.0 rods are supposedly stronger than the 4.2s. Last why is everyone having to run 91, did you raise the compression ratio?

Chip Clip said:

What pistons are you using. Also the 4.0 rods are supposedly stronger than the 4.2s. Last why is everyone having to run 91, did you raise the compression ratio?

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Pistons..
I am using generic 40 over 4.0L pistons.

Long explanation of why the 4.0 rods are better...
The 4.2: rods are approx 1/8" shorter than the 4.0L rods which helps lower compression back down a bit since the 4.2L crank adds about 1/4" more overall stroke (1/8" up and 1/8" down travel). There is a custom pisiton out there that moves the wrist pin 1/8" closr to the piston face so you can run the 4.0L rods on the 4.2L crank. The Geometry on the Longer rods throughout the rotation of the crank in relation to the piston doesn't change as drastically as the shorter rods reducing a lot of unneeded wear and tear.

Running 91
When you stroke the motor, you are adding more displacement into the stock engine space. Going from a stock 4.0 to a 4.6L add an extra .1L of air getting compressed into almost the same amount of space in the combustion chamber (combustion chamber could be massaged larger as well as using low compression pistons to help with this), which creates more heat. The hotter the air/fuel mixture is, the easier it is to combust and possibly detonate before the piston is where it needs to be in the stroke. Adding a higher Octane reduces the fuels ability to ignite under pressure/heat which is why it is needed in high compression engines to help prevent predetonation.

That being said, use the least octane that your engine needs to run in order for your engine to perform efficiently. If you use high octane and the engine does not need it, you will be losing power, wasting gas, and creating more pollutants due to the unburnt fuel.

Damn, the more I talk about this, the more I am wanting to build another Stroker, now
that I have a 14 year old son, would be a nice project for us...

John

That was a really good answer, HandBuiltXJ.

Skwerly said:

That was a really good answer, HandBuiltXJ.

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Why thank you, if only I could make a living out of this plethora of semi-useless information in my brain.

John