help me decide 289 or 347?

65notch · Sep 23, 2006

i just recently installed new heads and cam/lifters in my 289 a month ago or so and i got a bad lifter from edelbrock and it caused my cam to go flat...now i have metal throughout my engine. :-( at the same time the guide plates on my heads werent adjusted properly and it wore my push rods down...so i have all that metal in my engine too...
now i need a suggestions on what to do...

option 1:
its a 289 bored .030 over with about 30k miles on it.nothing special about the parts except arp rod bolts. the comp. ratio i was running was somewhere in the low 8s:1 i think (with stock heads i was running 9.2:1 and now i have 60cc heads so im sure i lost alot) so the question is should i tear this down, install new bearings and have the crank polished(asuming its not torn up to bad) etc. OR

option 2:
i have a stock 302 block out of a 70's car that ive planned on building into a 347 eventually. now that im without a running engine, im almost thing i should just build the stroker and install my new heads on it(edelbrock performer rpms)

im tight on money right now and i know just fixing my 289 will be much cheaper but if i have the option to build the 347 i would like to take it.

Im looking for an estimated cost of building a 347 shortblock, does anybody have a break down of how much they run, nothing extremly race, but something that will last and i can run hard at times.

thanks guys!

68torinogt · Sep 23, 2006

to build the 347 is going to be quite a bit mre than the rebuillt 289.

i say wait on the 347 until you can build it with the best parts.

D.Hearne · Sep 23, 2006

I can tell you right now, it wasn't a bad lifter, but the cam lobe failed to spin that lifter at the initial fireup. Also, if your pushrods wore down, they weren't hardened to start with. A 347 short block will cost you about $1300 minimum to build. I did my 331 for $1300, exclusive of cam, lifters & main girdle. I don't know that I'd use a 70's block as a starting point though, there are better blocks out there for not a lot of money. Roller blocks included. At least with a roller you won't be playing russian roulet with the cam break-in.

65notch · Sep 23, 2006

D.Hearne said:
I can tell you right now, it wasn't a bad lifter, but the cam lobe failed to spin that lifter at the initial fireup. Also, if your pushrods wore down, they weren't hardened to start with. A 347 short block will cost you about $1300 minimum to build. I did my 331 for $1300, exclusive of cam, lifters & main girdle. I don't know that I'd use a 70's block as a starting point though, there are better blocks out there for not a lot of money. Roller blocks included. At least with a roller you won't be playing russian roulet with the cam break-in.

i dont know for sure if its a 70s block. i need to get the casting number off of it and check. it came out of a 92 5.0 but i dont believe it was the original engine for that car. what do you mean the lobe failed to spin the lifter at startup? the pushrods where hardened steel ( http://store.summitracing.com/partdetail.asp?part=CCA-7827-16&N=700+0&autoview=sku )
why did you go with a 331 versus a 347? did you go roller? 1300 including the block?

D.Hearne · Sep 23, 2006

65notch said:
i dont know for sure if its a 70s block. i need to get the casting number off of it and check. it came out of a 92 5.0 but i dont believe it was the original engine for that car. what do you mean the lobe failed to spin the lifter at startup? the pushrods where hardened steel ( http://store.summitracing.com/partdetail.asp?part=CCA-7827-16&N=700+0&autoview=sku )
why did you go with a 331 versus a 347? did you go roller? 1300 including the block?

Flat tappet lifters spin in their bores, no spin = cam lobe and lifter wear each other out in no time. Had two cams do this. Too much lube, ans/or the lifter sticks in it's bore, and the cam lobe doesn't grip the lifter bottom enough to set the lifter in motion. I went with a 331 because of the potential for longer engine life and less stress on the block. Mine's a roller. Picked the block up from a local engine machine shop. Came from an 89 Lincoln Mark VII. The guy who left it there, didn't have the $$ to finish it, then sold the car. I picked it up, cleaned with new cam bearings for $100. Got the block, rods, and pistons with it. Sold the rods and new pistons for $50. Just gotta keep your eyes out for this stuff. A good 70's block is the D8VE block, it's got 10 more pounds of iron than the rollers and 15 lbs more than the earlier 70's blocks. Some of this is in the cylinder walls. Good way to punch it 60 over and then stroke it with a 3.4 crank to make a 352.

fastback brian · Sep 23, 2006

There is still a good chance your 289 will be fine, unless the oil pressure dropped and there is bottom end noise I say stick another cam in there and try again. Any metal big enough to damage the crank would have to pass throung the pickup tube, the oil pump and oil filter. Its not like you broke a roller lifter and have needle bearings in the oil pan. You may need to run a hone through the lifter bores to clean up any marks left from the torn up lifter. Find some good cam lube and use the comp break in lube. And you should be using hardned pushrods, I like the one peice trickflows from summit. Build a 331-347 roller block on the side.

enferno · Sep 23, 2006

you can rebuild a 289 the complete & right way for about 1500-1800

the 347 is going to cost 2.5 that easy

D.Hearne · Sep 24, 2006

enferno said:
you can rebuild a 289 the complete & right way for about 1500-1800

the 347 is going to cost 2.5 that easy

Why would a 347 cost that much? I did my 331 for $1300-give or take a few dollars. Paid $1275 for boring, clearancing,and decking the block and the price of the stroker kit. SRP forged pistons, Eagle cast crank, SIR rods, rings and bearings. Add another $180 for the main girdle plus the oil pump and you still don't get $1500.

enferno · Sep 24, 2006

D.Hearne said:
Why would a 347 cost that much? I did my 331 for $1300-give or take a few dollars. Paid $1275 for boring, clearancing,and decking the block and the price of the stroker kit. SRP forged pistons, Eagle cast crank, SIR rods, rings and bearings. Add another $180 for the main girdle plus the oil pump and you still don't get $1500.

including heads etc?

stangman16 · Sep 24, 2006

enferno said:
including heads etc?

he has the heads already.

67Dylan · Sep 24, 2006

fastback brian said:
There is still a good chance your 289 will be fine, unless the oil pressure dropped and there is bottom end noise I say stick another cam in there and try again. Any metal big enough to damage the crank would have to pass throung the pickup tube, the oil pump and oil filter. Its not like you broke a roller lifter and have needle bearings in the oil pan. You may need to run a hone through the lifter bores to clean up any marks left from the torn up lifter. Find some good cam lube and use the comp break in lube. And you should be using hardned pushrods, I like the one peice trickflows from summit. Build a 331-347 roller block on the side.

I was thinking the same thing, but would like to add you replace the oil pump & pick-up tube & clean/check the crank for any metal. If you can fix the 289 it'll give you more of an opportunity to save to build the 347/331. If you don't build the motor yourself and need a shop to build it, I recmnd Duffee Motorsport. They are off Union Hills near I-17. I've only had one shop build a motor for me and they are it; VERY stout 377.

As for the 331/347; I've owned 2 347's and 1 342 and have had no reliability or oil burning issues. The motors were very strong (mostly street) and put me in the 11's w/no problem. In the end it's gonna come down to combo.

Stanger007 · Sep 25, 2006

Since $ is tight, I too would just rebuild the 289.

If you decided to go with a 347, why not do it right and have a custom cam, the correct heads and supporting mods in place from the get-go. (More $)

So my vote is to stay 289 and perhaps build a 347 on the side as time and money allows. You'll be more happy with a matched 289 setup than a mismatched 347.

And don't fear the cubes, the 331/347 debate is (now) bunk, problems with oil burning and the location of the wrist pin are fixed.

Wes

D.Hearne · Sep 26, 2006

Stanger007 said:
Since $ is tight, I too would just rebuild the 289.

If you decided to go with a 347, why not do it right and have a custom cam, the correct heads and supporting mods in place from the get-go. (More $)

Wes

You answered your own question there. And what's wrong with Performer RPM heads on a 347? Surely you can't tell us they're the wrong heads.

Stanger007 · Sep 26, 2006

D.Hearne said:
You answered your own question there. And what's wrong with Performer RPM heads on a 347? Surely you can't tell us they're the wrong heads.

Oh dang I didn't see he had the RPMs. Sorry about that 65notch. That's what I get for running my screen resolution at 1920x1200!

Well dang it, if he's got the heads and the cam and has to rebuild anyway then heck yeah go big man.

Coleman · Sep 28, 2006

Rebuild the 289 for now.

help me decide 289 or 347?

65notch

New Member

68torinogt

Hey guys, guess what--I have a bi-pass!!!

D.Hearne

New Member

65notch

New Member

D.Hearne

New Member

fastback brian

enferno

Member

D.Hearne

New Member

enferno

Member

stangman16

Active Member

67Dylan

New Member

Stanger007

D.Hearne

New Member

Stanger007

Coleman

New Member

Similar threads

help me decide 289 or 347?

New Member

Hey guys, guess what--I have a bi-pass!!!

New Member

New Member

New Member

Member

New Member

Member

Active Member

New Member

New Member

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency