stroker kits

There are so many variables that a test like that would be so subjective. Its really a silly thing to even say, i mean really, its a performance motor, that is most likely going into a car that putts around on the street, or gets its ass handed to it at the track. Theres not much middle ground and i'd say about 2% of people would be concerned if they lasted for 100k miles.
 
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where is a good place to get a stroker kit,, i ve been lookin at dss and there not bad. summit dont anwser my questions.. lookin to do a 331 or a 347, my motor gave out after 1339 miles built buy a local shop, oil pump failed, took out the crank 3 rods and a e cam, all toast,
Your location says tri-cities im guessing in Washinton. You should call AD Performance in the seattle area. He has stroker kits on the shelf. I think the last time i looked forged kits were around 1300.00. I bought an assembled Dart SHP shortblock with forged internals recently and was about 4100.00. That was the best price I found anywhere!
 
There are I beams that will take over 1000hp, it is all about having the proper parts for the application.

sorry Rick I should have been a little more specific

"you get what you pay for"

put a $1200 stroker kit in a stock block

put a $$$$ parts in a dart or boss block

Which one is gonna out last the other?

And really, if you are putting a 347 or a 331 together how can anyone realistically worry about longevity? You aren't putting it together to baby it all the time are you?
 
EXACTLY. I agree with everything you said. There hasn't been any testing. There isn't any true evidence.

And yes, the logic behind the side loading is sound. The thing is, why do some people believe that there is some magic line drawn between a 3.250" stroke and a 3.400" stroke? As if the 331 will last forever and the 347 will spontaneously combust at any given moment. There is less than 5% difference in displacement between the two engines. I'd laugh if there was a test done and it was determined that there was a 5% difference in longevity, and the 331 lasted 100,000 miles but the 347 only made it to 95,000. It's a completely moot point, because you know neither one is going to last as long as a 302/306 would. If someone wants to cry about longevity, then don't build a stroker to begin with. Buy a Honda.

The funny thing is, a lot of the people who build 331s will take them to the track and absolutely beat the car like a scalded dog. And they're concerned with reliability?

I dunno, that's my take on it. I'll take a definitive power advantage over a mythical reliability advantage every day of the week.

I agree with this^^^

Also, consider this. Who on this forum is actually going to put 100k on their mustang's engine without pulling it out to upgrade something, freshen it up, or change setups completely?

Nik, I'll bet that fresh engine of yours never sees 100k because A) you're not going to drive it that much. OR B) I'm bored! let's make more horsepower!
 
And really, if you are putting a 347 or a 331 together how can anyone realistically worry about longevity? You aren't putting it together to baby it all the time are you?

I (and I can't thing of anyone else) don't always baby my stock 302, but it's gone 200,000+km without issue. Why should I expect less longevity because I added more displacement? I only drive the car hard about 1% of the time....but if the wear has increased to a significant amount 100% of the time, that's not much of a positive trade off as far as I'm concerned.

Adding power, shouldn't cost you longevity.
 
Also, consider this. Who on this forum is actually going to put 100k on their mustang's engine without pulling it out to upgrade something, freshen it up, or change setups completely?

Fair enough....but should changing out your top end set up also have to include pulling and rebuilding your bottom end everytime you get bored?

I put 3-sets of head and intake combinations in my last 302 and only went with new rings and bearings for piece of mind because of the mileage....not because it needed it. Big difference between wanting to and having to? :shrug:
 
I agree with this^^^

Also, consider this. Who on this forum is actually going to put 100k on their mustang's engine without pulling it out to upgrade something, freshen it up, or change setups completely?

Nik, I'll bet that fresh engine of yours never sees 100k because A) you're not going to drive it that much. OR B) I'm bored! let's make more horsepower!

Haha yep. I'll take option "B", please. I'm already plotting my next performance mod, and it will likely be a stroker bottom end of some sort... And it'll happen waaaaaaaaaaaaaaaaaaaay before 100K. Hell, probably before 10K on this engine, haha.

I (and I can't thing of anyone else) don't always baby my stock 302, but it's gone 200,000+km without issue. Why should I expect less longevity because I added more displacement? I only drive the car hard about 1% of the time....but if the wear has increased to a significant amount 100% of the time, that's not much of a positive trade off as far as I'm concerned.

Adding power, shouldn't cost you longevity.

Well, regardless of the 331 or the 347, you're increasing rod angle/side loading and increasing piston speed over a 302, so you're theoretically going to reduce engine life. There is a tradeoff there, and I'm not sure there is a way around it.
 
Well, regardless of the 331 or the 347, you're increasing rod angle/side loading and increasing piston speed over a 302, so you're theoretically going to reduce engine life. There is a tradeoff there, and I'm not sure there is a way around it.


How many documented failures have there been where the rod angle cause a 347 to fail?
 
Well, regardless of the 331 or the 347, you're increasing rod angle/side loading and increasing piston speed over a 302, so you're theoretically going to reduce engine life. There is a tradeoff there, and I'm not sure there is a way around it.

Perhaps not, but as I stated above. The 331 kits has been around for a long time and have proven themselves not only as a great performers, but to have the legs as far as longevity is concerned. When considering the two a few months back, I Googled for opinions and found dozens upon dozens of users that had 80...90....100K+ on their 331's. Couldn't find any high mileage 347's though? :shrug:

Perhaps the latest 347 kits are still too young to tell, perhaps they aren't making the mileage because of rod angle issues? There just doesn't seem to be a concrete answer?

How many documented failures have there been where the rod angle cause a 347 to fail?
There were plenty of issues with the old kits where the oil ring placement caused a useage and wear issues. Since the “fix” though, the results seem to be….inconclusive. It may no longer be an issue, or it may just be a case of too early to tell?
 
There were plenty of issues with the old kits where the oil ring placement caused a useage and wear issues. Since the “fix” though, the results seem to be….inconclusive. It may no longer be an issue, or it may just be a case of too early to tell?

The ring placement issue was an issue over 10 years ago, a 347 or 363 that is built right will not burn oil. Oil consumption also has nothing to do with the rods stressing the pistons.
 
The ring placement issue was an issue over 10 years ago, a 347 or 363 that is built right will not burn oil. Oil consumption also has nothing to do with the rods stressing the pistons.

That's why I said "older" kits. ;) The fact remains....that those older kits were faulty to the point where they were being rebuilt, redone, replaced with the newer style kits later on down the road.....which in turn means there aren't really many, or any high mileage newer 347's around to disprove the rod concerns. Get what I'm saying? :shrug:
 
What fails in a motor? Is it really the cylinder sidewall? It's not as if this puts more stress on the rings. Is it really related to the piston speeds? I mean, 3.4" really isn't that long a stroke. Piston speeds at a given RPM are higher in most of the american V8s today. There are also numerous examples of motors that defy the "rule of thumb" 1.7:1 rod:stroke ratio. Many are much shorter. I'm not buying the theory that a 347 is less durable or has less longevity, and I think you guys saying that there are no examples of 347s running to higher mileage are wrong. Absence of evidence is not evidence. We need guys with 347s to chime in and let us know how many miles they got out of their motors. We also need to take into account how they used the motor. Typically people building strokers are putting around on the highways. Slamming gears every day with a 302 would significantly decrease longevity, too.

Oh, and I'm thoroughly confident in my I-beam rods :)

Chris
 
Nik... I would prefer not to get back into the full explanations, but there are viable reasons to build a 331 instead of a 347 that do not rest on oil consumption or longevity concerns. You have seen those arguments, right?
 
Nik... I would prefer not to get back into the full explanations, but there are viable reasons to build a 331 instead of a 347 that do not rest on oil consumption or longevity concerns. You have seen those arguments, right?

Jog my memory...? I can't think of any off the top of my head. I could probably guess a couple, but I'd rather hear what you have to say first. :)
 
I mean, 3.4" really isn't that long a stroke. Piston speeds at a given RPM are higher in most of the american V8s today. There are also numerous examples of motors that defy the "rule of thumb" 1.7:1 rod:stroke ratio. Many are much shorter. I'm not buying the theory that a 347 is less durable or has less longevity, and I think you guys saying that there are no examples of 347s running to higher mileage are wrong.

I read a couple good articles after this thread on rod to stroke ratio. One was a post from a guy that works for reher morrison, basically saying that if there was a top 10 list on things to be concerned about when trying to make power, rod length would come in about 15th. You just want to fit the longest rod in the engine that the block will allow. The rod length is what it is. What i did find interesting is they said to use a short deck motor because the use of a shorter, straight shot, intake manifold and valvetrain package are far more important.



Importance of Rod Ratio? • Speed Talk

Good read on 331 vs 347 debate
http://www.strokerengine.com/RodStroke.html

That's why I said "older" kits. ;) The fact remains....that those older kits were faulty to the point where they were being rebuilt, redone, replaced with the newer style kits later on down the road.....which in turn means there aren't really many, or any high mileage newer 347's around to disprove the rod concerns. Get what I'm saying? :shrug:

You also answered my first question with another OLD 347 issue, So how many documented failures have there been where the rod angle cause a 347 to fail?
 
You also answered my first question with another OLD 347 issue, So how many documented failures have there been where the rod angle cause a 347 to fail?

None that I'm aware of.....but that's not because the rod angle was or wasn't an issue, it's because they had piston and pin placement location problems shortening their lives and causing oil usage issues that prevented the owners of these engines from putting on any miles.

Can't exactly test a crank and rod combination long term if it can't make it past the first 40,000-miles because of issues at the north end of the rod, can we? :shrug:

At best, that leaves the results as inconclusive. And last time I checked, the word inconclusive, didn’t translate to “proven”!

Look guys....don't misunderstand. I'm not against running a 347, if it’s longevity can be established. But thus far, it hasn't been.
 
Well Brian I think you may have explained it in your top post, you're running a 302 and are hard on it less than 1% of the time. It's a factory engineered piece. Now yes we can debate all day long how well a factory motor is built i.e. tolerances etc but a stroker is only as good as the person who builds it.

Everyone I know who owns a stroker motor beats on it 100% of the time and never put that kind of mileage on because of why they built the stroker motor in the first place. Kind of hard to gauge longevity at a 1/4 mile or cruise at a time!

There is no replacement for displacement!