Fox Bench Racing

[RangerJoe]

Ok, I know this is a little silly, but I have been debating with my brother-n-law over the weekend. He is doing a coyote swap now, but ran a 347 for years. I have a 331, and I always hear from him that I should have gone 347. So I asked him Sunday how much HP he thought his 347 made, he says 450fwhp (guesstimate).

I think he is a little high. Here was his combo:

347 at 10.5:1
Box stock tfs 170 heads
XE282HR
1 3/4 long tubes
Systemax intake with 70mm TB

So, what's the verdict? 450? More or less?

Personally I think my 331 will hang with his old 347 numbers (what ever they truly were). I will have a touch more compression, custom cam and the new AFR renegade 185 heads. Everything else will be the same.

Joe

 

[elarm1]

My money is on you 331 spanking his Coyote whenever he gets done with it...

 

[bentley429isBAC]

Way less. Sounds like 350 to the tire max. So maybe 400ish at the crank.

 

[RangerJoe]

My money is on you 331 spanking his Coyote whenever he gets done with it...

Thanks for the confidence, but those coyotes are pretty bad. The biggest advantage his car has over mine is it's basically a race car on the street. Mine is pretty much full weight with AC, power steering and power brakes. He runs a 10.5" slick at the track and I run a 235 drag radial, so I know he will be faster, I just think the 347 wasn't as powerful as he thought.

Way less. Sounds like 350 to the tire max. So maybe 400ish at the crank.

That's about where I thought he was too, maybe 410 at the crank.

Joe

 

[fordjunky]

Ok, I know this is a little silly, but I have been debating with my brother-n-law over the weekend. ran a 347 for years.
So I asked him Sunday how much HP he thought his 347 made, he says 450fwhp (guesstimate).

I think he is a little high.
So, what's the verdict? 450? More or less?

I say he is a little high.

The combo I had in my hatchback street car had
372rwhp & 400rw torque.
Adding the standard 15% drive train loss for a manual transmission = 428hp-flywheel.

347
T5
Ported Cobra
6037 Edelbrock performers slightly ported
Off the shelf cam
Ran low 11s on Et-streets.

Personally I think my 331 will hang with his old 347 numbers (what ever they truly were). I will have a touch more compression, custom cam and the new AFR renegade 185 heads. Everything else will be the same.

Yes it should "hang" since your comparing dyno #s.

I always hear from him that I should have gone 347

The old 331 vs 347 debate has been done.
The 331 & 347 cost basically the same so its the buyers decision.
Mechanically speaking, the 331 "only" has to turn about 300 more rpms (per gear) to match the 347.
The buyer should ask there self if they believe in that "there is no replacement for displacement" or not.
ET wise they will be tit for tat if the vehicles there mounted in are basically set up the same.



ET wise I see your "new" combo ET between 12.5 to 11.8 depending on the 60ft & 118-125mph.



Other
Guys with the new 50 motor "in trucks" range in ET between high 11s to 15s.
A friend of mine ran 12.0s in a new full body mustang 50 with a programmer & exhaust on street radials.



.

 

[RangerJoe]

@fordjunky

I ended up with the 331 because of my previous budget build and having to run iron heads (compression issues), so not really trying to debate the 331 vs 347, which is better argument, just more along the lines of which engine would theoretically make more HP.

The entire plan for this car since day 1 has been to have a nice driver that could make a trip to the track with the AC blowing cold, air the tires down, make an 11 second pass, and drive home. So I will be pleased with any thing sub 11.90 really. I know my car could benefit greatly from weight reduction and a set of slicks, but that's not really where I want to go with it.

I think he will get low 11's, maybe even a high 10 with his truck coyote by the time he is done. It should be interesting to watch.

Joe

 

[fordjunky]

so not really trying to debate the 331 vs 347, which is better argument,

But you are.

just more along the lines of which engine would theoretically make more HP.

This is part of the 331 vs 347 debate.








It depends on how you build the combo.
It depends on the parts used in the rotating assembly.
A 289 & 302 etc can make more HP than the 331 & 347.

All rotating assemblys pump air so
if you want to know which 1 rotating assembly will pump more air @ a "set rpm" between the all the available cubes (for the stock 302 block) between 289 to the 350, the 1 with the most stroke will pump more air.



.

.

 

[RangerJoe]

But you are.


This is part of the 331 vs 347 debate.








It depends on how you build the combo.
It depends on the parts used in the rotating assembly.
A 289 & 302 etc can make more HP than the 331 & 347.

All rotating assemblys pump air so
if you want to know which 1 rotating assembly will pump more air @ a "set rpm" between the all the available cubes (for the stock 302 block) between 289 to the 350, the 1 with the most stroke will pump more air.



.

.

I wasn't intending an argument with you, but if you look at the actual question I posted:

"So, what's the verdict? 450? More or less?"

My real concern was whether or not he was making the HP he claimed, I just mentioned that he seems to think I screwed up by building a 331, whereas I think mine will make just as much if not more. Not based on the cubic inches, but based on parts selection (heads and cam mainly).

Please don't take my response wrong, I'm not one to get into internet arguments here, but I think everyone here, including you, did a good job of answering my question.

Thanks,

Joe

 

[fordjunky]

Oh gotcha LoL.

I see now it was your bro-n-law that was making it more of a debate as he was just comparing the stroke alone as he said "you should built a 347 over the 331".
I say you both are correct to a extent in a basic statement.

Its like the saying goes "its not the size of the boat that matters, its the motion of the ocean that does" LoL.

Hind site wise you made your decision & he should respect it.






Looking at rotating assembly's in a physics manner makes it more interesting LoL.


.

 

[Boosted92LX]

I think people underestimate 347s. Look what edelbrock can do with them..

http://www.edelbrock.com/automotive/mc/crate-engines/ford-sb-main.shtml

Not plugging edelbrock, my point is, if that's possible, imagine some big afr or tfs heads.. I've got rpms on my car and plan on hitting it with about 9 psi.

 

[hoopty5.0]

I think people underestimate 347s. Look what edelbrock can do with them..

http://www.edelbrock.com/automotive/mc/crate-engines/ford-sb-main.shtml

Not plugging edelbrock, my point is, if that's possible, imagine some big afr or tfs heads.. I've got rpms on my car and plan on hitting it with about 9 psi.

Had to put my shades on to look at those things, lots of chrome going on there.

 

[Gearbanger 101]

I think people underestimate 347s. Look what edelbrock can do with them..

http://www.edelbrock.com/automotive/mc/crate-engines/ford-sb-main.shtml

Not plugging edelbrock, my point is, if that's possible, imagine some big afr or tfs heads.. I've got rpms on my car and plan on hitting it with about 9 psi.

You speak as though everything in that link is 347 specific? All those goodies apply to the 331 as well.

 

[Boosted92LX]

Had to put my shades on to look at those things, lots of chrome goingcomponentsere.

Yeah. A little shiny for my taste. But you gotta admit 500 hp is impressive for an n/a 302 based engine with edelbrock components. HP tv did an episode on them on a dyno. It was hard to imagine, but numbers don't lie. And I think there was a reason they didn't use a 331.

 

[hoopty5.0]

Yeah. A little shiny for my taste. But you gotta admit 500 hp is impressive for an n/a 302 based engine with edelbrock components. HP tv did an episode on them on a dyno. It was hard to imagine, but numbers don't lie. And I think there was a reason they didn't use a 331.

I always thought the 331 was better after reading this:
http://www.stangnet.com/mustang-forums/threads/302-stroker-information.719569/

 

[Boosted92LX]

I always thought the 331 was better after reading this:
http://www.stangnet.com/mustang-forums/threads/302-stroker-information.719569/

I absolutely agree with everything there, Collin. Especially this:


331 (5.315"/5.400" rod) or 347 (5.315" rod) - Daily Driver
347 (5.400" rod) - Street/Strip or Track Car

For you, a 331 would make more sense. For someone like me who is going to roll it out of the garage on the weekend and trounce it, a 347 (or 363) isn't a bad choice.

 

[fordjunky]

http://sbftech.com/index.php/topic,6087.0.html

 

[hoopty5.0]

http://sbftech.com/index.php/topic,6087.0.html

link only works if you are a member there.

 

[Gearbanger 101]

And I think there was a reason they didn't use a 331.

Really.....what do you think that reason was?

I absolutely agree with everything there, Collin. Especially this:


331 (5.315"/5.400" rod) or 347 (5.315" rod) - Daily Driver
347 (5.400" rod) - Street/Strip or Track Car

For you, a 331 would make more sense. For someone like me who is going to roll it out of the garage on the weekend and trounce it, a 347 (or 363) isn't a bad choice.

If you've honestly convinced yourself that a 331 isn't as track capable as a 347, then no amount of date, or real world results are going to convince you otherwise.

My 331 is veeerrry rev happy. What SLIGHT amount of horsepower/torque it gives up to the additional 16ci offered by the 347, it more than makes up for in high RPM capability.

FWIW, a 331 makes for a better daily driver for longevity reasons, not because of performance limitation.

 

[hoopty5.0]

Really.....what do you think that reason was?



If you've honestly convinced yourself that a 331 isn't as track capable as a 347, then no amount of date, or real world results are going to convince you otherwise.

My 331 is veeerrry rev happy. What SLIGHT amount of horsepower/torque it gives up to the additional 16ci offered by the 347, it more than makes up for in high RPM capability.

FWIW, a 331 makes for a better daily driver for longevity reasons, not because of performance limitation.

I didn't read that he said anywhere that a 347 is more capable. And while I wont assume I can speak for him, I wouldn't expect a response.

 

[Gearbanger 101]

331 (5.315"/5.400" rod) or 347 (5.315" rod) - Daily Driver
347 (5.400" rod) - Street/Strip or Track Car

Perhaps I misread it....but I was basing my response off of this breakdown. Not sure what other way there could be to take it?