[89coupe]

Id say in the Piston Choice for one. Most just wanna use your basic Mom and PoP piston(IE non offset pin).

[vristang]

Originally Posted by n2omike

Jay, what does a 347 take that a 302 does not? Where do most shops screw up 347 builds? What specifics do they "like"?

Thanks!

Wasn't that already answered before you asked?

what rings and how the rings were filed that will make or break any engine

[n2omike]

Originally Posted by vristang

Wasn't that already answered before you asked?

Specific common mistakes. I already know the machinist has to do a good job, but I was asking what SPECIFICALLY seperates the machine work requirements between a 302 and a 347.

Thanks!

[Jay Allen]

Hey Mike.

Now being serious, try finding a guy who can bore a straight hole and then hone it with zero taper. I have a block here right now that came from a very prestigious shop. This engine has burned oil from the get go. Has 10K miles has never run right and still smokes.

Its a 3.25" stroke, 5.400" rod and a 4.140" bore. Its the same platform as a 331 [ LOL ] but this engine was built for a class with a 350 cid max. It never performed, cam was swapped and became a 100% street engine.

The block work is a mess. I hate doing engine work any more.........this is darn near a total rebuild.

So the machine work is first.

Then when a guy sees a rail support, his brain falls out. To this day I don't get that one.......

Filing rings. What may seem as a mundane task is really quite important. Every engine builder has "their way" of doing it. Funny how each piston company wants wall to skirt clearance checked differently and filing rings is not tough if you pay attention.

The bore finish is pretty important too.

Mike now you know the way I post. I'll open your eyes and send you along your way, but I am not going to put in type how to build an engine so a dirt track guy in BFE can learn how to do it. It does not matter what the CID is, what the piston is, what the R:S ratio is, if the engine builder and machinist are good, then the results speak for themselves.

People should not blame a part for their incompitence.

Originally Posted by n2omike

Specific common mistakes. I already know the machinist has to do a good job, but I was asking what SPECIFICALLY seperates the machine work requirements between a 302 and a 347.

Thanks!

In terms of a high performance build with good parts, none.

If it is an OEM rebuild with 1/16 x 1/16 x 3/16 rings and a 600g piston, Stevie Wonder could rebuild that.

So one of you [maybe more] disagree with what I have been saying. On a pretty high end board with proven people, here are a few excerpts from a thread I find amusing as it relates to this train wreck.

Originally Posted by Darrin Morgan

People put WAY to much importance on this preconceived " ideal rod ratio" idea. Rod ratio is not a primary consideration when designing an engine. You get the deck as short as possible so the piston does not come out of the bore. That gives you better manifolding which will make ten times the power any " ideal rod ratio" would net you. You shorten the pushrod and make the valve train stable above 9000rpm. You make the piston ring package as compact as possible to get the pin as high as possible and that will make for a light weight, balanced (not top heavy) piston design, THEN you decide what rod connects the piston to the crank. Its not magic, its simple mechanics. People look at what Smokey yunick said and they take it out of context in my opinion. He said you should put the longest rod YOU CAN not the longest rod YOU CAN CRAM JAM OR MANIPULATE into the engine. I see people all the time screw up the engine combination to facilitate some preconceived ideal rod ratio and they wonder why the thing wont turn up and make power. The difference in the GM 358 NASCAR test engine from 5.250 inch long rods to 6.1 inch long rods was maybe 2ft/lbs and 2 HP. Not much to worry about. That satisfied the GM engineers that there is nothing there. Does a short rod make more TQ? Does a long rod make more top end power? It probably does but its such an insignificant amount, its not even worth messing with! If there was a major advantage or power gain in this, it would have been proven a long time ago and we could all put this to rest but no one has. I wonder why???????????

Originally Posted by Darrin Morgan

Yes, your correct. A "long" rod engine will side load the skirt less than a 'short" rod will. I will not argue that because its a fact, But, What is a LONG rod engine and what is short rod engine. Your perspective can change depending on who you talk to and what mind warping falsehood they may have read in a magazine this week.The current pro stock engines have rod ratios of 1.71 to 1. I don't think anyone can say that's a short rod engine. The one point I am trying to make is that trying to HIT some "ideal" rod ratio at the expense of other more important design criteria is a big mistake.

Originally Posted by Shaun

The 24 hours of Le Mans GTS class winning Corvette C5Rs (427 CID) ran a rod ratio of 1.5 (6 inch rod on a 4 inch stroke) on Nikasil liners by Perfect Bore. They decisively won GTS class in 2001 and 2002 I believe. They lost to the Ferraris in 2003, but beat them this year. The C5Rs also have done very well in other major endurance races.

Originally Posted by Darrin Morgan

In my opinion it has less to do with rod ratio and more to do with piston speed. Average, not instantaneous. Endurance engine builders try and maintain a mean piston speed of 4500 to 4800 ft/min. An endurance engine that operates above 5000 is considered HIGHLY stressed. The current NASCAR engines operate in that range and they are pushing the limits of metallurgy in order to achieve that. It has everything to do with longevity due to the inertia loads on the parts over time. The pistons do not start to" outrun the flame front" until the piston speeds exceed 6800 ft/min. The Asiatech engine has a mean piston speed of 4977 ft/min and the Corvette Le Mans motor has a mean piston speed of 4333 ft/min. That's not even close to 6000 ft/min.

IRL engine = 4225 ft/min
Pro Stock = 5991 ft/min
average comp eliminator engine = 5800 ft/min
IHRA Pro Stock = 7400 ft/min OUCH! They don't last long at this speed and they nose over after the power peak big time!

Originally Posted by Mike of Lewis Racing Engines

Here is my take on rods, I posted this on another forum a while back in response to losing power in a 400 small block from using a "short" rod:

Short answer, Basically you are not losing anything.

My preference is a 6" rod simply because it makes internal balancing much easier with reasonablly priced parts but power wise don't expect any "magical" gains with a longer rod.

There are arguments for both short & long rods & in my opinion the best rod is the one that is long enough to connect the piston & crank together & leave you enough room for internal balancing.
Their is a minimal gain in regards to cylinder wall loading which gets way overblown in a longer rod,, but the shorter rod will move away from TDC SLIGHTLY faster which should tend to help crappy heads or restricted intake stuff.

I feel Rod length is one of the most over rated, over discussed parts of engine building.
I favor a rod long enough in strokers to be able to clear the needed counter weight as it normally makes balancing easier. If the rod is too short you can't get enough counterweight on the crank to balance it.
If you were to take the crank angles differences between say a 5.7 & 6" rod & overlaid them on a graph you probably wouldn't be able to differentiate between the two lines on the graph!

This subject was brought up & was summed up pretty good at the Advanced Engine Technology Conference a year or two ago in a round table discussion with some of the very best in the business of engine design in NASCAR.

This ain't a direct quote but I believe it went something like this:
You decide on a stroke, design a piston to fit your needs, measure the deck height of the block & then make something to hook them together. As I recall, that was pretty much the consensus on the importance of rod length in overall engine design.

Originally Posted by Racer7088 (Erik Koenig - Teacher at SAM in Houston, TX)

This is also what I have seen so I don't at all believe the hooplah about the long rod motors being any better at all. Also how could these large stroker turn in such nice BSFC numbers if they had extreme "sideloading" and friction? When cylinders are long enough to accomodate the stroke the wear even seems to be fine on the stroker stuff with the "short" rod ratios. I think cylinder heads and cams may need to be slighty different for each type of motor and that leads some people to think that low or high rod ratio motors are some how "better" before they really dial in either motor and see what it can really do. I know cubic inches always seem to be a good thing and they rarely come with better rod ratios either!

I can get more too.

[89coupe]

The details like Jay has pointed out, not to mention all the other factors, will quickly seperate the engine assemblers from the engine builders. And will also be shown at the track. Ill consider myself an assembler, as I'm far from having enough knowledge to be considered a Builder. I'm not afraid to admit it.

And this is not directed at anyone, but even if you have put together 50 engines, it still doenst make you a builder. These two titles are worlds apart, and only becomes apparent, when you actually talk or run across a true Builder.

It takes Experience, Knowledge, Attention to detail to be considered a builder in my opinion. Most guys only have one of the three. My only asset would be attention to detail

[Hanzou]

Originally Posted by Hanzou

I've read a lot about stroker kits in the last couple of months in preparation for a winter project. I do not have first hand experience at all... yet .

From what I have read the kits do not perform based upon their displacement. It there exist a happy medium for every block. This pretty much holds true for this argument. One side says displacement, lower rpm, etc. The other says higher rev limit, better clearance, longevity, hardly any difference in power output. One kit or two kits seem to have just the right setup to make optimum power. I think unfortunately maybe happy medium landed in between the 331 and 347


Personally I would go with the 331 and for no other reason than the fact that it does rev higher. On the street I feel it is more fun to have a larger range than more power.

What would be an estimate of the HP / TQ difference between the two kits? I can't imagine the HP is much different but TQ is probably significant.

I apologize for posting any of my thoughts on this topic. Thought I knew something about engines. I don't know sh!t.

[RLG34750]

Originally Posted by 89coupe

The details like Jay has pointed out, not to mention all the other factors, will quickly seperate the engine assemblers from the engine builders. And will also be shown at the track. Ill consider myself an assembler, as I'm far from having enough knowledge to be considered a Builder. I'm not afraid to admit it.

And this is not directed at anyone, but even if you have put together 50 engines, it still doenst make you a builder. These two titles are worlds apart, and only becomes apparent, when you actually talk or run across a true Builder.

It takes Experience, Knowledge, Attention to detail to be considered a builder in my opinion. Most guys only have one of the three. My only asset would be attention to detail

I will agree i too am a assembler......

attention to detail is one of the most important attributes you can have.....

also i found it not as important of knowing the right answer but knowing where to find it......

In so many words its not what you know its who you know.....

(now 89coupe stop calling me.....)

Originally Posted by Hanzou

I apologize for posting any of my thoughts on this topic. Thought I knew something about engines. I don't know sh!t.

No need to apologize this thread has humbled a few of us myself included......

the important thing is that you have learned something from it.......

[347Vert]

Originally Posted by 89coupe

In other words, to market their block( which they screwed the pooch on) they had to use the 3.250 stroke

While you and a few others apparently think Ford Racing "screwed the pooch on" the Boss four bolt main block by their designed limited deck height, how about an alternative view? Why would they do this on a four bolt main block?

Just suppose they did not make a mistake and purposely lowered the deck height to limit the stroke. Maybe Ford Racing wanted the stroke limited to keep the rod/stroke ratio within a "good ratio" when preparing a "race motor" - isn't this where a four bolt main block is needed? Just suppose, they do know the importance of rod/stroke ratios as not only do they make a "race block" limiting the stroke to the magical 3.25 stroke, but then again chose the 331 for their all out race crate motor as a result.

But some want to discount Ford Racing, "comic books" Hot Rod and MMFF, and my points as not knowing or making mistakes or hidden revenue agendas detracting away from the fact of the importance of rod/stroke ratios in race motors. Anyone who totally disregards rod/stroke ratios in preparing a race motor is someone to be wary of taking advice from.

Moving on and it sounds like some others are needing it more than me. Take care and GOD bless.

[Joel5.0]

Originally Posted by 347Vert

While you and a few others apparently think Ford Racing "screwed the pooch on" the Boss four bolt main block by their designed limited deck height, how about an alternative view? Why would they do this on a four bolt main block?

Just suppose they did not make a mistake and purposely lowered the deck height to limit the stroke. Maybe Ford Racing wanted the stroke limited to keep the rod/stroke ratio within a "good ratio" when preparing a "race motor" - isn't this where a four bolt main block is needed? Just suppose, they do know the importance of rod/stroke ratios as not only do they make a "race block" limiting the stroke to the magical 3.25 stroke, but then again chose the 331 for their all out race crate motor as a result.

But some want to discount Ford Racing, "comic books" Hot Rod and MMFF, and my points as not knowing or making mistakes or hidden revenue agendas detracting away from the fact of the importance of rod/stroke ratios in race motors. Anyone who totally disregards rod/stroke ratios in preparing a race motor is someone to be wary of taking advice from.

Moving on and it sounds like some others are needing it more than me. Take care and GOD bless.

From the FRPP catalog regarding M-6010-BOSS302 block, the third "Tech Note" specifies:

• Maximum recommended stroke 3.400"

However, in the case of the Boss 302 block I would go with a 4.125" x 3.250" 347 instead, due to the cylinders length issue and even though the real Ford Racing specified stroke limitation is 3.400".

The point of this discussion is not a "total disregard of rod/stroke ratios", the point of this discussion is that at the level of both alternatives (aka 331 and 347 configurations) rod/stroke ratio does not have the significance it is given to make it a decisive factor to choose one over the other. When ALL the other characteristics for a street or racing setup are evaluated...... specially when all the factual experience regarding performance and durability from the track, from the street, is evaluated; a 347 does have the upper hand. No conjectures, no what if's, no suppositions..... facts.

[vristang]

Originally Posted by 347Vert

While you and a few others apparently think Ford Racing "screwed the pooch on" the Boss four bolt main block by their designed limited deck height, how about an alternative view? Why would they do this on a four bolt main block?

Just suppose they did not make a mistake and purposely lowered the deck height to limit the stroke. Maybe Ford Racing wanted the stroke limited to keep the rod/stroke ratio within a "good ratio" when preparing a "race motor" - isn't this where a four bolt main block is needed? Just suppose, they do know the importance of rod/stroke ratios as not only do they make a "race block" limiting the stroke to the magical 3.25 stroke, but then again chose the 331 for their all out race crate motor as a result.

Make no mistake about it... this guy is going WAY out on a limb making ASSumptions about what Ford was doing in their design. This 'average Joe' hasn't a clue about any of the design features that the engineers were limited to (same as anyone on this board).

ASSuming that the deck height was limited in order to keep the R:S in a specific range is a mistake.

This is what is known as 'Twisting the Data'....

As evidenced by Joels quote from the FRPP catalog....

Maximum recommended stroke 3.400"

This 347Vert guy is ignoring certain data and only acknowledging the data that supports his theory.
Not a good thing to do if you want to continue to improve yourself and/or your ride.

Originally Posted by 347Vert

But some want to discount Ford Racing, "comic books" Hot Rod and MMFF, and my points as not knowing or making mistakes or hidden revenue agendas detracting away from the fact of the importance of rod/stroke ratios in race motors. Anyone who totally disregards rod/stroke ratios in preparing a race motor is someone to be wary of taking advice from.

Moving on and it sounds like some others are needing it more than me. Take care and GOD bless.

The magazines are in business to sell advertising space to automotive retailers/manufacturers. Magazines do not exist in order to provide you with tech, they exist to SELL you parts. They print what ever the paying customer wants them to print.
If you want to use a true technical resource, then I suggest spending some time and $$$ on the SAE site searching their archives. SAE documentation is written by PROFESSIONAL Engineers working in the Automotive Industry, as opposed to magazines which are written by English/Communications majors....

As an example....
I read in MM&FF several months back, that they couldn't 'Set their TPS' after an engine replacement, because they didn't have the right equipment.
All you need is a fracking Volt Meter... and that only applies if your TPS is our of the EEC range!
Instead these teabaggers waited until they got to the chassis dyno to have the TPS set and fuel pressure adjusted.
The point is, the author didn't own the most basic automotive tools, and didn't have an understanding of the basics of tuning an EEC-IV Mustang.
These are the same guys that 347Vert is taking technical advice from

In regards to spreading technical information.... the magazines do more harm than good.

[Jay Allen]

Originally Posted by 347Vert

While you and a few others apparently think Ford Racing "screwed the pooch on" the Boss four bolt main block by their designed limited deck height, how about an alternative view?

You? Singular or Plural? Who is this even tossed at?

Now make no mistake, what I am about to do is ALL at you. Singular of course.

Where did I say anything about a boss block being limited by deck height? Funny how I had my hands on a Boss 351 block about 3 months ago.

Ought Oh.......Ford has another block?

Put a 3.00" stroke in a 9.500" deck block. Use a 1.250" C/H pistons and a 6.750" rod! You'll have a 2.25 R:S ratio and it'll do everything you need it to do!!!

But it won't turn the tires over in wet grass.

Originally Posted by 347Vert

Why would they do this on a four bolt main block?

Do what? You think they "purposely" lowered the deck height? Funny, I thought a 289 and 302 blocks since 1964 1/2 were all 8.2 deck?

Ford did NOTHING purposely

Originally Posted by 347Vert

Just suppose they did not make a mistake and purposely lowered the deck height to limit the stroke

It makes me vomit when I hear about stroking a 302 (8.200" deck) and how 3.400" is pushing it.

I have built engines with 3.550" strokes in them. You use a SBC 434 piston (1.00" C/H) and a SCAT 5.400" rod. In a stock block at 4.030" you can have a 362.2 cid engine. And BTW Pastor Vert, a 1.00" C/H 434 SBC is very common in the real world.

I know of guys who run 3.600" stroke, regularly. Chris Uratchko (URE - one of the BEST engine guys) is toying with a 3.700" stroke and a 1.00" C/H using a 5.350" rod and a Honda 1.880" bearing. This is in a 4.200" bore block.

Wait! Stop the press! You Cannot Do That!

4.200" Bore x 3.700" stroke = 410.1 cid from a 302 block.

5.350" rod / 3.700" stroke = 1.446 R:S

Originally Posted by 347Vert

Maybe Ford Racing wanted the stroke limited to keep the rod/stroke ratio within a "good ratio" when preparing a "race motor"

Yes, I am sure Brian Wolfe and the Boys built an engine to appease you.

Its about the MONEY!

Originally Posted by 347Vert

isn't this where a four bolt main block is needed?

Turbo 347's that shift at 6800 RPM that run bottom 8's high 7's on DR tires.......that's where a 4 bolt block is needed.

Originally Posted by 347Vert

Just suppose, they do know the importance of rod/stroke ratios as not only do they make a "race block" limiting the stroke to the magical 3.25 stroke

Did you NOT read the posts from Darrin Morgan I brought over?

Originally Posted by 347Vert

But some want to discount Ford Racing, "comic books" Hot Rod and MMFF

Even at a discount they are not worth buying. For free they are good to start a fire with while camping.

Originally Posted by 347Vert

and my points as not knowing or making mistakes or hidden revenue agendas detracting away from the fact of the importance of rod/stroke ratios in race motors

Dude, you have been flat PROVEN what works.

I ASKED YOU SEVERAL TIMES FOR THE DELTA CHANGE IN TORSIONAL LOAD. I ASKED YOU WHEN WOULD MY 347 FAIL AND HOW MUCH MORE LIFE WOULD A 3.25" STROKE HAVE.

Originally Posted by 347Vert

Anyone who totally disregards rod/stroke ratios in preparing a race motor is someone to be wary of taking advice from

The truth is I have done it and you can only dream of it.

[89coupe]

As far as I know, its not a deck height issue, its cylinder length. Meaning the cylinders are shorter. The R:S ratio is a minimal factor at the most, considering the block can handle it. Why build a block that keeps customers from using one of the most popular stroker combos there is. Technically this would hurt their sale. Unless they came up with an escape route. Which they did by using the R:S factor. Again, what about the offset pin that some of the piston manufactuers use?

Why the R:S maybe the same, wouldn't the offset pin put the side loading amount close to that of the 331? I would think so. As the angle of the rod has changed during the stroke.

Dang, Jay posted about the deck height while I was posting it seems.

[ScottHalliday]

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For those of you who participated in this thread in good faith and found themselves under personal attack for voicing their opinion, I sincerely apologize on behalf of AllFordMustangs and our moderator team.

We encourage ALL members to voice their opinion without fear of retaliation, ridicule and personal insults. Instead of personal attacks and ridicule to fight what one may consider "disinformation" we encourage members to post their opinion as to what they perceive to be correct and proceed from there with a healthy respectful debate from which others will learn. As long as the correct information is posted, members and viewers are quite capable of picking the bones out if it. Our job as moderators of this site is to facilitate that discussion and encourage members to post their differing opinions by having respectful and informative discussions. Not to encourage or tolerate flame wars or personal insults between members.

Over the last two hours each post within this thread has been carefully reviewed. As a result, all posts containing frivolous comments, inappropriate comments and/or disrespectful comments have been deleted, or have been edited and those comments removed.

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Regards,

[Joel5.0]

Originally Posted by ScottHalliday

Administration Notice

This thread was reported to our site administrators for containing inappropriate and disrespectful comments towards members of this site. This is clearly against our site rules and will not be tolerated under any circumstance.

For those of you who participated in this thread in good faith and found themselves under personal attack for voicing their opinion, I sincerely apologize on behalf of AllFordMustangs and our moderator team.

We encourage ALL members to voice their opinion without fear of retaliation, ridicule and personal insults. Instead of personal attacks and ridicule to fight what one may consider "disinformation" we encourage members to post their opinion as to what they perceive to be correct and proceed from there with a healthy respectful debate from which others will learn. As long as the correct information is posted, members and viewers are quite capable of picking the bones out if it. Our job as moderators of this site is to facilitate that discussion and encourage members to post their differing opinions by having respectful and informative discussions. Not to encourage or tolerate flame wars or personal insults between members.

Over the last two hours each post within this thread has been carefully reviewed. As a result, all posts containing frivolous comments, inappropriate comments and/or disrespectful comments have been deleted, or have been edited and those comments removed.

Any further violations of our site rules within this thread will result in an immediate infraction being issued which can result in an immediate and permanent suspension of your membership privileges.

Regards,

Let me use that statement highlighted above to express the following opinion regarding opinions then:

1. May I humbly inquire what is the title of this section? ... Isn't it "5.0L Tech"? ...as in "technology"? Which is "The scientific method and material used to achieve a commercial or industrial objective." or, "The application of science, especially to industrial or commercial objectives."
2. Are "opinions" valid in regards to technology, other than speculating their future trends?
3. Is it acceptable, as an example, to steer the decision of a member regarding his project's body paint with magazine based information, even though I'm a neophyte with no real experience in today's body paint tech, by using the "opinion" excuse?
4. If the above is allowed, and fostered, even after causing that member to waste $$ based on my inexperienced/ill-informed opinion and is left untouched, accessible to public view, so others may incur in that waste..... who could be identified as liable?
5. Opinion is an acceptable political, medical or juridical term, where the probability of failure, or lack of accuracy, are very well expected..... yet this is a car performance technology related area. FYI.... even the lack of proof or real knowledge is included in one of the definitions for opinion: 1. A belief or conclusion held with confidence but not substantiated by positive knowledge or proof.
6. I work solving car related problems every day.... "opinions" are the #1 cause for customers to waste money trying to solve car problems w/out a proper diagnostic and the reason why I'm always busy ...... but that is also the #1 reason why I will never provide an opinion based diagnostic, which is an oxymoron concept. A diagnostic requires proof, facts and data to hold validity, and ensure the customer only spends what is required to solve a problem... not waste his hard earned money.
7. The above is not only the correct business practice to follow.... it is the right thing to do. Or why do you think the "opinions" joke cliche exists?

Now... opinions aside. Do you really expect that a person, with God only knows how much experience with real stroker setups, should keep a passive/patronizing discussion attitude on a topic in which, the debating side has no REAL facts and experience, other than 3rd party information (aka: magazine articles, speculation on engineering approach, etc).... and expect a courteous reply, when all his field based facts are questioned? .... without any real proof to the contrary?

OK... never mind the explanation above. Do you know that you have a misinformation/disinformation tech topic in the stickies above regarding "How to properly set your TPS"? ... or haven't you noticed the facts based replies I have posted in that sticky?.... yet the misinformation is kept, w/out tagging it as such, so EEC-IV neophytes can continue doing something that a) is not required, and b) can cause damage to their properly functioning TPS....... why?

Finally.... and before this gets misinterpreted.... this is not a "flame" to your post. I do know the pressures admins go through, under a more facts/tech oriented environment by the way. However....... it is my opinion, that any reply made by any member, that cannot be sustained by personal facts/experience, is the continuance and nurturing of the ricer approach. Ricer approach and TECHNOLOGY is also an oxymoron..... in my humble opinion, that is.

[fast88]

EXCELLENT post Joel

.....Hopefully it wont get pulled down or edited.

Rich