As it stands, I want to just swap the 302 in the bird for another SBF, just debating what. So far, I got another 302, a 347, or a 351. I am thinking staying 302 based as most of my aftermarket stuff is 302, but from summit a new 351 replacement is like $3k turn key. Any oppions welcome, let me know what you guys think. I got 4 more months to think about it before I come stateside again
I had a 351w put into my 85 bird. I love it with exception to the gas mileage.... abot 13mpg.
depends on what you planing to do with the car.
if it something you want to drive on reg base ,then stay with roller block 302.
if it some kind of toy, then go 351!
If you building for performance, a 347 is pretty hard to beat. It has considerably less rotating weight than a 351, allowing to accelerate much quicker. If you already have 8.2" based block intake & headers stroking a 302 makes even more sense. Keep in mind: 302 parts make 302 power.
If you are interested in being educated on why a 347 makes sense, check out this link: http://sbftech.com/index.php/topic,7864.0.html
There is an incredible amount of great information on that site if your interested in building an engine right the first time. The "Net" has lot of nonsense regarding how to build an engine to go fast. Lots of arm chair experts. SBFTECH.com is not one them. It is a no BS site that will give you right answers based on facts (not talking magazine tech articles looking to sell parts here). Word of caution though. Read up on what's in the Myth sections before you post any questions. If you can't find what you need there, ask away.
351... You can make more power on a stock block(although not a good idea) and if you stroke it you'll have more power and torque then a 302 base block could.
Everything I got so far is 302, so I'm heavely biased twards that. How much to gain, power wise vs. money spent, with a 347
stock or stockish...302 otherwise i would do a 331
well to make a 347. you have to have a 3.4inch+ stroke crank! so you have to have the wristpin into the oil ring groove. so every one knows that will cause your 347 to BURN OIL.
327/331 is the most i would go with on a stock302 block because then you have 3.25 stroke crank. which means no wrist pin in the oil groove.
food for thoght:
if you go with a dart block 302. which can be bore to 4.125 and put in a 3.25inch stroker crank
supposedly CHP has solved this. reguardless id still go 331
if your going 347, you might as well go 351W
As of now, parts list include:
Summit Stage 2 intake
Polished edel 600 E choke
E303
Roller 302 w/ .030 over
GT40's with port match
High volume oil pump
Holley mechanical fuel pump
Pertronix FULL igniton system ( box/dizzy/wires/coil)
Waiting on choosing the slugs as well as crank before I finally decide the size I want to go for. Might change the cam up as well. You guys should know whats in the car now, only things that have changed is the intake and igntion.
:dunno:
anyway....
carbed...if it were me i would build up a 351W
I stated what parts I have for the new motor, not whats in it, but good catch. I was really considering the 351 untill I figured out I would need another intake, another dizzy, swap headers and oil pan ( I think). The only way I will do that plan is to put the 302 into the stang and the 351 into the bird. I belive I have a few pics floating around from my last leave period when I was just mocking parts into place if ya need
... so pretty much you already had a plan and you were just trying to spam the board.
Think about it... "I have these parts", Do research (It's called a search button), and then start a thread about how you're putting this combo together and it better have some pics.
...
FWIW there are plenty of threads here and in other message boards that have all the info required for you to make a decision.
Thanks for being of absolutly no help. The post count was a nice bonus though, seeing as MOST of those are in one thread. Atlest my posts were semi-productinve in one way as opposed to sheer wasted space and constant put downs.... it really makes a big difference in helping to decide which of the 302 based engines I want.
To everyone who is actually TRYING to help me out here, I think I got it down to 331 or 347. Anyone who has experience with them, what is the big difference minus the 16 cube difference? More power, rev's faster... Is there any real bonus to those extra cubes? What would me a major difference between the two? The car will be mostly a cruiser with some strip time.
The choice between the 331/347 will vary depending on who you ask. You will hear, as some have posted, the oil ring issues with the 347. This is true when the initial 347 kits were available. This is not the case now. The costs for the 347 is the same for the 331. You just get MORE power with the larger displacement.
The ultimate decision is yours. Determine what your goal is for the car and go from there. Someone has already given a link to SBFTech. You should go there and read on the (non)issues of the two different engines. This is a no bullsh*t site that gives straightfoward answers to legitimate questions.
Good luck and keep us informed on what you decide!
Thank ya much
Mikey
that was an issue, not anymore. that is why any 347 purchased today does not really add up to 347 but a little less. Your only major disadvantage to any stroker kit is rod angle wearing down the center area of your cylinders due to the larger main to rod journal distance.
engineers have not figured out a work around on this one yet, ive often thought if this ever became in issue, a man could always sleeve his block,,problem solved. The "347" has more rod angle but generates more cubes. The 331 splits the difference between 302 and 347 making the best of both world but yet it still has an effect on your cylinder walls as far as rod angle is concerned. EIther way, I think the 347 is probably the best option but be rational on the build and dont &uck it up or you just ate a stroker kit.
Rod angle is a pretty interesting read and opens your eyes to the science of a single stroke. Chevy's 302 would out stroke a ford 302 well into the rpm's you could only dream about. Now go and find out why.
im going to assume longer rods and taller block?
no special block, same size stock chevy 302.
Rod angle wear is what happens when you install a stroker kit.
the main bearing center line ratio to the rod bearing center line is greater than stock.
when any given rod journal comes around from bottom dead center (lets call this 6 o'clock) and moves to the 9 o'clock point, the rod angle with respect to the piston is at its greatest obtuse measurement. The crank is still going to send the piston up but within that area spanning the middle of each bore, there is excessive friction on the wall. Most of this reason is due to the reduced height of the piston so with a shorter piston, and at max rod angle, the wear is going to happen and it can not be helped.
This is why the 331 splits the difference between both worlds. Just a little bit of rod angle and a little bit more cubes.
rod angle is like when you want to jump in your snow boots real fast but your in a hurry and slightly off target. Said boot bends and you twist your ankle:D
The illustration below is exagerated but you should get the point.
The advantages to stroking in my opinion out weigh stock strokes but my two favorites are increased dwell and a more rapid air / fuel suction.
The increased dwell on a stroker allows the piston to hover longer in the TDC or BDC position. On the combustion stroke, the piston hangs out longer on TDC while the spark plug lights up and fires your fuel. The piston being up in the TDC range longer is like a ticking time bomb because all that fuel is still igniting. Once that piston starts going down, it creates more power,, all this because of a longer dwell.
The increasted stroke also pulls in a higher velosity of fuel and air (making more air/fuel options possible now) which complements the increased dwell characteristic.
Its a give and take though,, matter of opinion.
I suppose the only way around getting rid of rod angle wear is to have a flexible connecting rod (lol)
I can see why the idiot was banned again. Already fighting with people and spending mucho $$ without having a plan to pay back those who were wronged. Dumbass.
BTW, there are slightly shorter rod (5.31 versus 5.4) kits from Probe that keep the piston pin a little lower and allow more room for the ring pack. A nice tight well built 347 can easily last 100k miles - which is likey longer than the attention span of the average enthusiast who can't keep things the same for very long.
OTOH, it really does come down to deck height and the correspondingly short piston required for such a short deck and long stroke. I think the biggest issue with the 347 is piston stability (rocking) causing ring sealing issues. Oil burning is the worst. Most 347's that don't burn oil from the git-go were built tight enough to keep the piston stable. A good tight non oil burner will likely last a long time before skirt/cylinder wear become a major issue.
I too can see why he was banned again.
Plus he was becoming a post w and filling the board with garbage.
Yeah, he's gone. This thread has become, like him, redundant.:locked: