331 stroker

[Ethyl Cat]

It's just a passionate exchange of ideas and opinions.

With a lack of conversational nuances "

Yes Pace I know. I got a little carried away.

A guy from NZ quoting NWA! Now that is bad ass. New Zealanders with Attitude?

Gift for you Xctasy. A long rod 302 combo that I have never seen built in my life in any article in any book ever. Not gonna say it has never been done though. I was saving it to build as an experiment some day ( And maybe prove myself wrong, huh?) . Should be right up your alley as some of the parts come from down under.

P.S. I never said I did not like long connecting rods!

Prepped 302 hyd roller block.

Prepped stock stroke 302 crank

Holden 308 connecting rods 5.627" long. You can have the rod journals widened when the crank is ground then cut the big end slightly narrower to get rod side clearance. The crank pin on the Holden is 2.124 vs the Ford 2.123" so you can get Ford bearings to work.

347 stroker piston of your choice 1.090" compression height. Cut .015 off the top to get 0 deck on the 8.2" 302 block. Pin is .927 on the Holden as it is in all 347 pistons.

Rod/stroke ratio comes out to be 1.88:1

Should work best on engines using stock type heads that are going to be spun up to 7000 rpm or a little more.

Cam will definitely be the key to getting the combination optimized.

Anybody on FEP wants on let me know. You could be the first one.

My resources are everywhere. Books (hundreds in my library), discussions with other engine builders (of all types of engines), my engine builds (all types) , simulation software, applying mathematical formulas to every engine I can get full data on to find trends thru spreadsheets and on and on.

I try to do my best to trim it down to the basics and cut the BS out. I do not post links, you have to choose to believe me or not.

Formula one engines (pre 6 cylinder turbo) BMEP comes in at around 220-230. I would not say that is a fail for an N/A engine.

Please do not go away X, you are the only person that butts heads with me! I gave you a nickname now, you're stuck

[xctasy]

LOL...As if I would go away. Where and in what Galaxy??. Hmm, The Snickers bar you offered above was nice..at least has stopped me playing like Betty White...

Oh and just for the record...


You gave the cam info...I didn't. Because I pay the man at Ivan Tigue or Kelford Cam tech, and they use similar programs to you, but don't have access to even half the master profiles you would. So ball one, I missed.

Ball two.

What a pissing match this has become.
Call Ed Curtis and be done with it.

Wasn't even a p___ing match...Steve won, I missed

Ball three

It's just a passionate exchange of ideas and opinions.

With a lack of conversational nuances

Mostly my opinions...with a tenous base, I missed the factual home base, and I'm tagged out..


In the final analysis, As for the long rod thingy, yeah, I know, its the substantiation of hp loss that is mixed up with a whole bunch of things that the V8 jury says are the caustive factors. And probably right on the money. I may have taken 10 or 30 years to think wronly, Add 2 and 2 and get 22.

My gut instincts think that mathematically, you can filter out the details by dimensional anaylses. It took years for use to discover how pushrod engines rocker arms rubbed, and some really daft ideas were proven via Harland Sharp/Harvey Crane/ Jim Millers comparisons. Sometime the answers right under your rocker.

Whatever, here's the David Vizard article. Chapter 14, pages 385 to 391 of the 2nd Edition of the 192 page Paperback by Fountain Press Ltd; New edition edition (Jan. 1984), so called Second Edition, ISBN-10: 0863430414, ISBN-13: 978-0863430411


Its base engine a bored out, stock 1275 5.75" rod engine with 3.206" stroke and 74 mm 2.913" pistons. 1399 cc. L/R = 1.794:1

The other so called 74 mm bore engine has a 91 mm 3.583" stroke with 5.75" rods engine is 1566 cc. L/R = 1.605:1

For simplicity, like DV does, the capacity difference is normalised to 1.142, 1400 to 1600 cc. If it was actually 1.142 bigger, due to it maybee had 74.7 mm Triumph TR6 2500 piston Omega make, taking its capacity to 1595 cc. He was pretty vauge on that, but the deck and the chamber had to be massaged, but its as apples verses apples as you can get. 0.7mm is almost 30 thou.

http://i1215.photobucket.com/albums/..._80850_385.jpg

http://i1215.photobucket.com/albums/..._80860_386.jpg

http://i1215.photobucket.com/albums/..._80870_387.jpg

http://i1215.photobucket.com/albums/..._80912_388.jpg

http://i1215.photobucket.com/albums/..._80912_388.jpg

^ Page 388

http://i1215.photobucket.com/albums/...G_8092_389.jpg

http://i1215.photobucket.com/albums/..._80921_389.jpg

^Fig 14.4 on Page 389

http://i1215.photobucket.com/albums/...G_8093_390.jpg
http://i1215.photobucket.com/albums/..._80932_390.jpg
http://i1215.photobucket.com/albums/...G_8093_390.jpg

^Text and Fig 14.5, 14.6 on Page 390

http://i1215.photobucket.com/albums/...ee686921db.jpg
^Fig 14.6 Page 390

http://i1215.photobucket.com/albums/..._80941_391.jpg
^ Page 391 Conclusion

On the table losses described. Its all about hp per liter for him, but for me, its about why the difference. For those of us with SBF 5.0's on a Stroker Ace mission, perhaps the similarities aren't there becasue of the over square nature, but for me, I've epxerienced the latancy of big inch strokers in small blocks, and would give anything to get the sweetness of the smaller engine. The normal frictional losses and inertial ramming chart that Stan Weiss uses for specfic power verses engine size covers some of this, but frictional losses for me were due to L/R.

[Fearnot]

So tonysilver82, did you get anything out of this?

[FUKAZ28]

So tonysilver82, did you get anything out of this?

[Walking-Tall]

That is way too much duration at .050" for the OP's engine. 236@.050" degrees would put the peak hp closer to 7000 with his heads. The exhaust port on the OP's heads are killer so .595" and a ton of duration are not necessary.

If he had gt40p heads with a 331 it might be closer to ideal. Remember the better the head the less cam you need.

With the cam I suggested (20 degrees less seat to seat and 16 degrees less @.050) I have his engine cranking at 200-220psi and making 460+hp at 6200-6500 and around 440 tq. It also averages 384 lb/ft from 1500-6500!

I am surprised that your peak is @ 6000. What math/software are you using to arrive at that number?

A 2.02 valve has enough cross section to feed even a 331 up to and past 7000 rpm. With more than enough head one must be careful not to allow too much curtain area, slowing the air down or closing the intake valve too late and not trapping maximum intake charge.

Peak piston demand on a 331 @6500 is only 264 cfm and the 185 cnc flows 300cfm @ .600

Just read the second link that Pacefever provided and it is a great example of what I am talking about.

Yes, people get paid quite a bit of money to tell you in private what I am telling you here. I have about 40 minutes of time with $1000 plus in software and my experience in this thread already. Just on the camshaft stuff mind you. The discussion with Xctasy more than doubles that!

Just an opinion, based on a number of equipment assumptions, with interpretations of the OP's descriptive wanted running manners, as well as heavy consideration of available pump gas octane, based on what I've read and learned over the years (David Vizard comes to memory), is that apparently 200psi is pretty much the ceiling for pump gas use without having to pull a bunch of ignition timing out of the equation.

[Ethyl Cat]

Just an opinion, based on a number of equipment assumptions, with interpretations of the OP's descriptive wanted running manners, as well as heavy consideration of available pump gas octane, based on what I've read and learned over the years (David Vizard comes to memory), is that apparently 200psi is pretty much the ceiling for pump gas use without having to pull a bunch of ignition timing out of the equation.

And I may be a little close to the limit with the cam suggestion. I tend to look a little more at how the dynamic compression turns out along with how modern the combustion chamber is and make sure the builder puts the engine together with proper squish.

This one ended up at 8.6:1 dynamic which is a maximum value for pump gas, so it can be adjusted some from there. I have not had a conversation with the OP and by the looks of it probably will not.

My intentions for street cams is to maximize the averages, that way it has more manners, good bottom end and pulls hard to red line.

The amount of pcm tuning also would come into play on this one as well.

[tonysilver82]

So tonysilver82, did you get anything out of this?

yes the third reply and when I received the engine the cam in it is a compcam #35-775-8 was told that was what dss specified for this engine

[Ethyl Cat]

Wow, is this a strip/street application you intend for this 331?

Peak torque is going to be around 5500 rpm. You better put some 4.10's or 4:30's in that thing.

Pretty sure that cam will knock the bottom end tq right out of it.

[tonysilver82]

Wow, is this a strip/street application you intend for this 331?

Peak torque is going to be around 5500 rpm. You better put some 4.10's or 4:30's in that thing.

Pretty sure that cam will knock the bottom end tq right out of it.

yea that some of the reason was gonna get a different cam its a driven street car and partial track

[Walking-Tall]

yes the third reply and when I received the engine the cam in it is a compcam #35-775-8 was told that was what dss specified for this engine

lol... I should apply for a job at DSS? That Comp Cam is a near match to the TFS grind I mentioned, but with less lift and 114-degrees lobe separation, where the TFS has 110-degrees lobe separation. I think you'll be hard pressed to make "a dog" out of a 331 stroker, even with 236-degrees at 0.050, and besides, for a probable comparatively small trade-off, who doesn't like some rumpity-rump idle with their pump gas friendly compression ratio?

Good luck with it,
Mike

[Ethyl Cat]

lol... I should apply for a job at DSS? That Comp Cam is a near match to the TFS grind I mentioned, but with less lift and 114-degrees lobe separation, where the TFS has 110-degrees lobe separation. I think you'll be hard pressed to make "a dog" out of a 331 stroker, even with 236-degrees at 0.050, and besides, for a probable comparatively small trade-off, who doesn't like some rumpity-rump idle with their pump gas friendly compression ratio?

Good luck with it,
Mike

Two wrongs do not make it the right cam.

The upper green and red lines are my cam. The other two are the Comp cam that came with the engine

[FUKAZ28]

That is a big difference.

[Ethyl Cat]

It sure is.

[Walking-Tall]

Two wrongs do not make it the right cam.

The upper green and red lines are my cam. The other two are the Comp cam that came with the engine

Wrongs? No comment... besides that your (honestly very impressive, maximized area-under-the-curve, etc.) resultant theoretical expectations are debatable as well (though I'm not here to argue with you), which brings to the forefront that this question was asked for opinions, bringing about everybody's interpretations as to what's "good" or "right".

Friendly advice to the OP: be sure to come back here to thank "Ethyl Cat" for his opinion if you follow it closely to the letter duration-wise, for if/when the car requires 105+ octane gas, commonly available at airports, or for having to do timing tables editing/tuning to the computer to decrease ignition timing across the board so that it doesn't end up detonating itself to death. Whichever route you choose, good luck and have fun with it.

[Ethyl Cat]

Wrongs? No comment... besides that your (honestly very impressive, maximized area-under-the-curve, etc.) resultant theoretical expectations are debatable as well (though I'm not here to argue with you), which brings to the forefront that this question was asked for opinions, bringing about everybody's interpretations as to what's "good" or "right".

Friendly advice to the OP: be sure to come back here to thank "Ethyl Cat" for his opinion if you follow it closely to the letter duration-wise, for if/when the car requires 105+ octane gas, commonly available at airports, or for having to do timing tables editing/tuning to the computer to decrease ignition timing across the board so that it doesn't end up detonating itself to death. Whichever route you choose, good luck and have fun with it.

I understand your concern about cylinder pressure as it is a concern of mine as well.

Rest assured that this cam cranks at 175 psi and has a dynamic of less than 8:1.(Not at my fun computer right now or I would give the actual) I did back the ICL up 4 degrees to 107 for the graph provided to help insure that the very real things you warn about do not happen.

Point of reference: Just completed an EFI 406 SBC (10.3:1 AFR 195 comps) Cam installed was a 280/282 221/223 @.050.

I did not spec this one but it did come from one of the top designers in the country. Pump gas deal at the limits. 200 psi crank and 8.5:1 dynamic.

It can be done....

Steve

[xctasy]

All of your references are for engines that are induction limited and a longer rod can help these engines dues to a delay in demand from the piston. Your math was done 30 yrs ago! In your specific examples your theory may have merit, but you are missing the real reasons why the increase/decrease happened. Also, you most definitely cannot apply it to every engine.

EC. Rather than stealing your info without payment.

I've thought about the 5.6" Holden rods on a 302, but it ends up back tracking to the error ridden reverse stroker issues, not furthering the science.

I've through about this long and hard. I'll take "our" tonysilver82 Level 10 D.S.S 331 5.0 EFI stroker with Trickflow 185 CNC heads, Trickflow Upper and Lower intake. It is indeed a Non induction limited engines.

Challenge you to a Stroker 331 engine duel.

I've got access to a 30 thou over 302 9.206" deck Cleveland block,
Which can fit those Trick Flow 185 heads with a 1.1" deck 347 piston.
Calibration of ECM is easy, there's many suppliers.
The TFS intake is easily replaced with a cut down 5.8 lower intake to suit the 1" deck height difference.
Down here 1972-1982 Y, P and B VIN code 4.9liter 302C Clevelands out number 1970-1982 T, K and H code 5.8 351C engines 5 to one anyway. The only made 3/4 of a million, and 425,000 were 302C's, 75,000 were 351C's.
From 1992 to 2003, only 50000 5.0 302W engines were imported into Australia for Falcons, Fairmonts, Fairlanes and LTD's. So I can get a 4.9 Cleveland easy as.

Cleveland closed chamber 57 cc 302c 2V heads usually either crack, or get sold off. So you find losts of Kiwi market blocks that are planned for 351C duty were born understressed 240, 207, or 188 hp 2 or 4-bbl 4.9 Liter Falcon, Fairmont, Futura, Fairlanes and LTD engines anyway.

I have access to a stock 302c crank which can easily be indexed via offset grinding to a 3.25" stroke crank, with small journal 6.5" rods. Main bearings can be downgraded to 302 Windsor 2.4" via machined shims, reverse stroker 400 Chev style.

Something similar was a common jet boat category engine since way back.

6.50"/3.25"= L/R 2:1 verses your best 5.4/3.25 L/R 1.66:1.

20.8% difference in ratio.

Lets settle on all the stock with the assumption the ECM is stock A9L modified to suit, with upgrade to whatever injectors safely meet the pulse width requirements.


My first enginerebuild was a 5.8 351c 2v with 375 hp.

I can build and sell an engine like your best 331 choice, but with a Cleveland block for the same cost as a factory roller cam 5.0 block.

The early 302C engine blocks are 569 pounds dressed (same as the Boss 351, and were in fact made in the US and exported to Australia), and Cleveland iron blocks just need the upper deck plugged to run Windsor alloy heads, and engine like that would fit into any modern Fox engine bay with an afterarket sump and dipstick tube. And maybee a Capri or aftermarkt hood scoop.

If I supply my two best optimized roller cam specs, would you please be kind enough to plot on your program the relative increases in hp and torque?

The percentage difference in max power and torque, you can be the final judge.

[PaceFever79]

Someone say Cleveland power?

[Ethyl Cat]

I am intrigued but a little confused Xctasy.

1st do you think this should be a different thread in the race section? If so , start one and I will meet you there.

I am all for doing something that will have the potential to educate.

Are you saying that you want to run the numbers on the same engine with different cams? Am I designing something?

I need real good details on the engine you want to build so the numbers are accurate. PLease post everything you have.

Try to condense your thoughts into bullets so we can all play along.

Sounds like fun

[xctasy]

Cool. I'll pop it into another post. 2:1 rod ratio stroker verses 1.66:1 rod ratio stroker.

"Cost effective 331 stroker base Windsor 5.0 or Cleveland 351?"

http://vb.foureyedpride.com/showthre...65#post1765565


It is however very relevent to the D.S.S 331 Stroker because of what Tom Naegele says below.


from http://www.mustangandfords.com/how-t...l-block-build/

When rebuilding a tired 5.0, the question is not if a stroker kit makes sense, but which one. For years, 347s reigned supreme, but currently 331s are the rage. We asked D.S.S.' Tom Naegele for his opinion, and we got a scientific answer.

"It depends on the application," Tom says. "The 331s are typically 40 hp better at 6,000 rpm (than a 347). If you have a light car-3,200 pounds or less-and a five-speed and a gear, a 331 will usually outperform the 347. In a heavier car, the 347 will outperform the 331. We recommend 347s to the guys with lower rpm, higher-torque applications."

Why does the 331 outperform the 347 at higher rpm? Because, as Tom puts it, "the 347s have too much piston speed at 6,000 for the best ring seal. They have a poorer rod ratio, rub the cylinder wall, and are not the most efficient combination, but they make good torque at 2,000-3,000 rpm."

So, the higher the rpm the more the 347's inefficiencies come into play. At lower engine speeds, the 347's greater torque speaks loudest, but even so, "the 331 usually does better on the typical 5.0 street car," Tom says.