302, 331, 347, or 351... that is the question

Topic: 302, 331, 347, or 351... that is the question (Read 5269 times) previous topic - next topic

302, 331, 347, or 351... that is the question

January 02, 2009, 12:15:25 PM

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

302, 331, 347, or 351... that is the question

Reply #1 – January 02, 2009, 12:30:24 PM

I had a 351w put into my 85 bird. I love it with exception to the gas mileage.... abot 13mpg.

302, 331, 347, or 351... that is the question

Reply #2 – January 02, 2009, 04:50:33 PM

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!

302, 331, 347, or 351... that is the question

Reply #3 – January 02, 2009, 04:58:22 PM

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.

302, 331, 347, or 351... that is the question

Reply #4 – January 02, 2009, 05:48:23 PM

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.

302, 331, 347, or 351... that is the question

Reply #5 – January 03, 2009, 12:53:54 AM

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

302, 331, 347, or 351... that is the question

Reply #6 – January 03, 2009, 01:38:25 AM

stock or stockish...302 otherwise i would do a 331

302, 331, 347, or 351... that is the question

Reply #7 – January 03, 2009, 02:13:29 AM

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

302, 331, 347, or 351... that is the question

Reply #8 – January 03, 2009, 02:19:55 AM

Quote

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.

supposedly CHP has solved this. reguardless id still go 331
if your going 347, you might as well go 351W

302, 331, 347, or 351... that is the question

Reply #9 – January 03, 2009, 03:53:09 AM

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.

302, 331, 347, or 351... that is the question

Reply #10 – January 03, 2009, 01:06:53 PM

Quote

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.

Quote

The cam was changed when I put on a new waterpump and changed the timing cover to a mechanical fuel pump kind. The exact cam numbers I am not sure, but it's a summit brand cam. I'll try to look it up later for you guys. I think I have some pictures of the install as well. Also, much has been changed since you have seen the car on FTCF but not "changed" in it's own right. When you last saw it, it was a Holley 4160 on a stock 83 stang intake with a py MSD box and a duraspark dizzy. Now it has full pertronix igniton(wires/box/dizzy/coil), a new Edelbrock 600 on a new summit stage 2 intake.

anyway....
carbed...if it were me i would build up a 351W

302, 331, 347, or 351... that is the question

Reply #11 – January 03, 2009, 01:17:38 PM

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

302, 331, 347, or 351... that is the question

Reply #12 – January 03, 2009, 06:33:08 PM

... 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.

302, 331, 347, or 351... that is the question

Reply #13 – January 03, 2009, 08:27:02 PM

Quote

... so pretty much you already had a plan and you were just trying to spam the board.

Quote

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FWIW there are plenty of threads here and in other message boards that have all the info required for you to make a decision.

302, 331, 347, or 351... that is the question

Reply #14 – January 04, 2009, 04:11:14 AM

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.