306 vs 347 stroker

[90mustangGT]

I'm with you on that one ... ohhh how I know your pain

However many things look great on paper, and Voila! ... work out in the real world as well ... like the new MGW shifter I just ordered

Your right sometimes they do. I guess it all depends on the quality of the engineer and where their priorities and goals are set. The engineers that designed the newer GM trucks and SUVs I would like to shake thier hand, the one's who designed the Chrysler Concord, LHS, Intrepid I would like to kick them square in the nuts. Back to the stroker...

We can argue about rod ratio's and how they effect longevity but when your racing someone that is the last thing on your mind. We all know that the weak point of the 302W block is right down the middle, not the cylinder walls, so with that in mind STROKE IT LIKE A ASIAN MASSAGE PARLOR!!!

 

[_jb_]

Wow...I was having a hard time deciding to go with 331 or 347...now it's even more confusing...

Oh well, I still have most of the summer time to think about it

 

[5.0_Gil_89]

I agree if it's built right it'll last, plus what are you building it for? Longevity, race street strip? I'd want a bullit "proof" assemble myself. But if it was me I'd go Dart 8.2 and stroke it to 360 CID plus. 4.100 X 3.40, or 4.125 X 3.40 363 CID. That's what I'm shooting for next year depending on where Uncle Sam puts me next. If the 347 scares you go with a better choice of block and parts. Go for longevity, unless you are racing the thing. JMO...too many folks build or ask for a race motor then get mad when it doesn't last. Go for longevity, you can always race it. You want something that is fast but can take the riggers of everyday stop and go traffic. Thanks USA!!!!

 

[SPEED FREAK]

Oh i was an engineering major, now a geo major because engineering was booooring.

LMAO me too

 

[SPEED FREAK]

OK riddle me this batmen.... The ford falcon of australia (the current model) uses a 347!!!!! It's the 302 based stroker some of you seem to fear... So why if it is such a bad motor why is it original equipment in some cars??? Fact is the days of the oil burning piston slapping 347's are over LONG OVER so get over it and stroke away. While your at it why not just step up and do a 351w based stroker not that I'm biased or anything.. BE WARNED I will slap the crap out of anyone dumb enough to tell me a 351w conversion is expensive or hard.

 

[2000xp8]

Just get the god damn motorsport 347, it's $2300 bucks, and is factory reliable.

 

[SPEED FREAK]

Ahmen.

 

[89CopCoupe]

Just get the god damn motorsport 347, it's $2300 bucks, and is factory reliable.

Cheers ...

Did motorsport ever correct the pin/groove intersection issue with their 347 design

 

[89CopCoupe]

Originally Posted by 89white50
Oh i was an engineering major, now a geo major because engineering was booooring.

LMAO me too

You betcha ... 'cause most every other profession is SOOOOOOO exciting

 

[89CopCoupe]

OK riddle me this batmen.... The ford falcon of australia (the current model) uses a 347!!!!! It's the 302 based stroker some of you seem to fear... So why if it is such a bad motor why is it original equipment in some cars??? ....

Oh yes, and Ford produced the Pinto too .... Ka-BOOM!!
.. and Peugeot built .... well, the Peugeot.

 

[5spd GT]

OK riddle me this batmen.... The ford falcon of australia (the current model) uses a 347!!!!! It's the 302 based stroker some of you seem to fear... So why if it is such a bad motor why is it original equipment in some cars??? Fact is the days of the oil burning piston slapping 347's are over LONG OVER so get over it and stroke away. While your at it why not just step up and do a 351w based stroker not that I'm biased or anything.. BE WARNED I will slap the crap out of anyone dumb enough to tell me a 351w conversion is expensive or hard.

I would like to see a link to this Falcon with a 347...and see what it's market is.

It is simple. More piston up and down motion causes more wear which ='s the 347 compared to the 302/306.

 

[89CopCoupe]

We can argue about rod ratio's and how they effect longevity but when your racing someone that is the last thing on your mind....

100% with you there .. I stated so in a prior post about preferrring a 347 ... this all started 'cause someone made a comment about longevity and so I kicked a lil' knowledge out.

That's all.

 

[89CopCoupe]

I would like to see a link to this Falcon with a 347...and see what it's market is.

It is simple. More piston up and down motion causes more wear which ='s the 347 compared to the 302/306.

Some people live in a zero friction world, logic is pointless here.


I'm with you, I'd almost always take a 331 to a 347 ... exception being a heavy vehicle that needs the bit extra torque down low.

 

[2000xp8]

Cheers ...

Did motorsport ever correct the pin/groove intersection issue with their 347 design

I was never fully aware of the actual problems with the original (although i knew there was one), but i see it used on a constant basis with no problems. It's probably the most cost effective way to get 400+ to the wheels NA.

 

[89CopCoupe]

A few years ago they were built with the standard (302) 8.2" deck height block ... 5.4" rods ... and a crank with 3.4" throw ... plus pistons with typical centered pins ...

Based on these factors the piston pin bore intersects the oil control ring land (bottom ring)...

They will consume a little more oil. Just wondered if they made the necessary changes?

 

[Grn92LX]

It is simple. More piston up and down motion causes more wear which ='s the 347 compared to the 302/306.

Which also ='s 4.6's, 331's, 351's, 408's, 418's and any other engine with more stroke than a 302 (going by your logic) If your going to use that logic, be fair

 

[90Notch]

Longevity:

The piston in a 347 travels faster (at the same rpm) than a 302 due to the longer stroke ...

Simple physics : 1000rpm .. distance traveled by piston = 3.0" (302) vs 3.4"(347) per revolution

... the 347 must travel a greater distance in the same amount of time ... therefore it moves faster in the cylinder.

Plus a 347's rotating assembly has sharper angles and greater force in typical direction changes due to both size engines being confined within the same size box or block.
... 347s side load the piston into the cylinder with greater force therefore creating greater friction and greater friction creates greater wear.

First I have a question for you, have you ever built a 347ci stroker ran it then tore it down to evaluate this greater wear? I have and you might want to try it...interesting results. Also, I have a few friends running 347 right now, one is approaching 90,000 miles, another just over 100,000 and last one has @ 50,000. All beat the hell out these motors and they are all still running very strong.

Using your engineering/pyhsics theory how do you explain the longevity of Honda motors specifically the B18C5, which has the following specs:

8.347" deck height, 3.189" bore, 3.433" stroke, 1.195" compression height, 1.89" journals and makes 195 HP @ 8000rpm? This motor is clearly making more friction, as well as, applying more force to the side wall than a 347.

 

[2000xp8]

A few years ago they were built with the standard (302) 8.2" deck height block ... 5.4" rods ... and a crank with 3.4" throw ... plus pistons with typical centered pins ...

Based on these factors the piston pin bore intersects the oil control ring land (bottom ring)...

They will consume a little more oil. Just wondered if they made the necessary changes?

Well, supposidly the hypertectic pistons help keep oil consumption low, and it's now made with the sportsman block, not the stock one.

 

[5spd GT]

Which also ='s 4.6's, 331's, 351's, 408's, 418's and any other engine with more stroke than a 302 (going by your logic) If your going to use that logic, be fair

Oh so they use the exact same piston rings/rods/skirts/ratios/etc...

I didn't know that...so if your going to use that logic...make the variables the same

So 351's are in your average performance vehicle meant for longevity/performance, as well as 408's or 418's??? Why compare them to the 302/306 as far as longevity or the 347. They all have their different reasons for what they are. Are all 331's ratios the same...nope. So if your going to use that logic...make it fair

So the 4.6 has the same setup as a 5.0L based engine

Again it is very simple...more up and down piston motion (friction as alluded to) will cause more wear. You can't leave that on the table...it is there and always will be until the end of time. It doesn't solve the wearing issue of a 347 from the past...because of the laws of friction. You can't solve that completely like what has been said about how "those are of the old days" type problems...

 

[Grn92LX]

Again it is very simple...more up and down piston motion (friction as alluded to) will cause more wear. You can't leave that on the table...it is there and always will be until the end of time. It doesn't solve the wearing issue of a 347 from the past...because of the laws of friction. You can't solve that completely like what has been said about how "those are of the old days" type problems...

You just proved what you tried disproving According to you, "more up and down movement = more wear". 331, 4.6, 408 whatever ALL have MORE up and down movement than a 302.

Well said, 90Notch Experience > text books

I wonder how erik K from hardcore50 managed to get over 185k out of his 3.40 stroke car?