306 or 331??

[fivespeedsteed]

if your trying to go sleeper, or even close to it, dont go 347. they have a distinctive sound. the wrist pin issues have been solved as said above... shouldnt have to notch the block to clear 331, but you will for 347. i vote 331.

 

[86nu]

I could understand the 306 for a car that's getting h/c/i, but paying for all new gaskets and seals, just to put stock parts back on, just doesn't make sense to me.

I realize not everyone has h/c/i money lying around, that's why i say in this case, get a complete maf engine from the JY, comp and all.

Head bolts, hg's, and the rest of the parts are going to add up quicky.

86nu, i've seen a bunch of 347 combos run 10.50-11.0 NA, in a street car, a 351 isn't going to do much better, if any.

Ive seen 351's goin 9's n/a, we can play whos balls are bigger all day long

 

[Modular2v]

a 331 will have to have the cylinder skirts notched for the rod bolts to clear!

 

[2000xp8]

Ive seen 351's goin 9's n/a, we can play whos balls are bigger all day long

Not sure how many fully equiped street cars i've ever seen in the 9's NA, but it really doesn't matter anyway here, he's re-using the stock top half of the engine.
Which is why i say to just get a used complete engine.

 

[ninety15.0]

I would also say theres no point to a stroker of any kind with a stock Head and cam car. A cobra intake really isnt enough to supply a good 331 or 347 and the stock heads are going to kill that setup. I would say build a nice solid 306 bottom end and then you can always throw a mild HCI on there and FI and get to respectable power numbers around 400 RWHP. Strokers are way more expensive than just the extra couple hundred bucks for the rotating assembly.

 

[1991vert]

347.

i had a 347 and decided to bore it out even more to a big bore 363. i plan on boosting the crap out of it. it's all in the machine work. too many internet warriors on it whining about the 347 "problem" that has LONG AGO been solved.

think about it. if 347s were that poor of a design and had that many problems, would they still sell them?

 

[5spd GT]

347.

i had a 347 and decided to bore it out even more to a big bore 363. i plan on boosting the crap out of it. it's all in the machine work. too many internet warriors on it whining about the 347 "problem" that has LONG AGO been solved.

think about it. if 347s were that poor of a design and had that many problems, would they still sell them?

The 347 isn't a 'poor design', but it's design on the piston with a 5.4" rod causes the wrist pin to move into the oil control ring. Blow-by will occur, but I didn't say immediately

What rod you using by the way?

Also, I have read a user on here saying that they would have got the 5.4" rod if it wasn't on backorder. This makes no sense to me. I would not 'supplement' my engine with something I wouldn't want and would drive with if that is all I needed. I would wait.

Like I said, if you get a 347 and want longevity and better 'oil control', get the 5.315" rod. I don't think anyone said it is a 'poor design.' It has it's pros and cons. You can make a 5.4" 347 go for quite sometime, but the 5.315" rod is a better design ergonomically.

In short, for the 347, get the shorter rod, taller compression height piston and not the longer rod, shorter compression height piston. Get the same cubes and more efficient life

 

[1fastsn95]

I would also say theres no point to a stroker of any kind with a stock Head and cam car. A cobra intake really isnt enough to supply a good 331 or 347 and the stock heads are going to kill that setup. I would say build a nice solid 306 bottom end and then you can always throw a mild HCI on there and FI and get to respectable power numbers around 400 RWHP. Strokers are way more expensive than just the extra couple hundred bucks for the rotating assembly.

I do plan on getting a custom cam that will support S/D setup. Then later on down the road get some better heads and MAF. Im wanting a good solid foundation to start with. I understand that the stock heads are going to choke the hell out of it, but Im preparing for the long haul. Also the 331 stroker kit is not "way more expensive" than the 306. Check out Summit. The kit is only like $800 or so. I know it doesnt come with as much, but overall its not that much more than the 306.

 

[5spd GT]

Check out www.adperformance.com for stroker prices and kits. When you call, speak with Brian, I hear he is the man to talk too on getting people hooked up with good prices and everything you or your machinist will need.

Prepare to buy a new flywheel and balancer along with that stroker kit.

 

[1991vert]

Check out www.adperformance.com for stroker prices and kits. When you call, speak with Brian, I hear he is the man to talk too on getting people hooked up with good prices and everything you or your machinist will need.

Prepare to buy a new flywheel and balancer along with that stroker kit.

i bought my stroker kit from brian and it's a 5.4" rod.

i always see you running your mouth about how a 5.315" rod is better than a 5.4" rod. do you actually have a 347? have you ever had one fail or seize up on you? has one ever had "severe blow-by" ? have you ever seen a rotating assembly besides online?

 

[Rick 91GT]

The 347 isn't a 'poor design', but it's design on the piston with a 5.4" rod causes the wrist pin to move into the oil control ring. Blow-by will occur, but I didn't say immediately

What rod you using by the way?

Also, I have read a user on here saying that they would have got the 5.4" rod if it wasn't on backorder. This makes no sense to me. I would not 'supplement' my engine with something I wouldn't want and would drive with if that is all I needed. I would wait.

Like I said, if you get a 347 and want longevity and better 'oil control', get the 5.315" rod. I don't think anyone said it is a 'poor design.' It has it's pros and cons. You can make a 5.4" 347 go for quite sometime, but the 5.315" rod is a better design ergonomically.

In short, for the 347, get the shorter rod, taller compression height piston and not the longer rod, shorter compression height piston. Get the same cubes and more efficient life

The 5.4 rod was on backorder so I was able to upgrade Mike to a lultra ightweight 5.315" rod to meet his time frame. I wouldn't call that a supplement, I'd call that a free UPGRADE..lol

I prefer the 5.4" actually.....revs a little quicker in most instances. I've stopped arguing this point a long time ago and build both with my customers and sell both sytle rotating assemblies as well.

In theroy yes the 5.315" rod will last longer due to design but there are stock Chevy combos out that run forever with a lot worse Rod to Stroke #'s... The difference in CH is .085"


How the car running Dave?

 

[5spd GT]

The 5.4 rod was on backorder so I was able to upgrade Mike to a lultra ightweight 5.315" rod to meet his time frame. I wouldn't call that a supplement, I'd call that a free UPGRADE..lol

I understand that part, but he was willing to sacrifice a major component of the engine because he couldn't 'wait' any longer My point is, I don't care if it was on backorder, I'd wait to get the part I wanted

I prefer the 5.4" actually.....revs a little quicker in most instances. I've stopped arguing this point a long time ago and build both with my customers and sell both sytle rotating assemblies as well.

Yeah, I bet it does rev up quicker, it is that very slight edge I was talking about.

In theroy yes the 5.315" rod will last longer due to design but there are stock Chevy combos out that run forever with a lot worse Rod to Stroke #'s... The difference in CH is .085"

Yeah, there are a lot of rod ratios worse than 1.5x, but I never said that was the reason for blow-by or wear. From what I have seen, I see more higher mileage with less rod ratio cars. I have seen the charts of the different rod ratios and engines for those rod ratios. I do not see the same 'per capita' engines running as long as something with less of a rod ratio, but I don't want to get into that

And the difference in piston speed is even less, at .0411 or something like that

How the car running Dave?

It's running fine, thanks for asking I'm just putting money towards money that are more important right now It's bitter sweet I guess...

 

[5spd GT]

i bought my stroker kit from brian and it's a 5.4" rod.

i always see you running your mouth about how a 5.315" rod is better than a 5.4" rod. do you actually have a 347? have you ever had one fail or seize up on you? has one ever had "severe blow-by" ? have you ever seen a rotating assembly besides online?

Cool.

No I do not have a 347 cubic inch engine under MY hood. I have friends with them. I do lots of research and see what works and what doesn't. I look through bias and make more individual decisions. I was not aware that you need a 3.4" stroke and a 5.4" rod to be an expert I could name 3 stangers that I know that have a 347, that doesn't even know what it takes to get that displacement. Does that mean they know more than I do, because they have a 3.4" stroke and a 5.4" rod

No, I have not had one seize up on me. I have seen blow-by though

I have seen more rotating assemblies than I could care to count I have took a tour of Keith Craft's shop, and I'm ALWAYS at my buddies house/garage. They race dirt track cars. Engines all over the place. I have seen my own. I have seen friends. Like I said, more than I care to count