348 To 380 Dyno results

[1964SuperStocker]

We are both happily married to very nice women, me for 45 years +.

We live about an hour apart and he has a 66 and I have a 63, superior to a 66, I have a 409, superior to a 348, I have a 4 speed, he has to deal with all these 2 pedal problems.
Other than that, I’d trade him my 409 for his 348. I’d keep the wife (haven’t met his yet so nothing personal), and the 63.

Its actually pretty cool that someone would put a 348 from a truck in a 66 SS, pretty good choice I’d say.

I don't know about the 409 being superior, they both suffer from identical mechanical issues. If you can't get it done with a 348 then it doesn't matter how many cubes you add. 348 is historically first, numerically first and when you type in this web page 348 comes before 409. 700hp can be made with a 348 and few of us have that much hp in a 409 with any stroke. They made more 348's then they did 409's and the only reason people buy 409's is because they love the Beach Boys! (I have their records, cassettes, CD's, mp3 files.... )

 

[DonSSDD]

I guess I have to say this again, no replacement for displacement.

 

[1964SuperStocker]

I guess I have to say this again, no replacement for displacement.

If that statement were true then we would all have 600+ cubic inch engines and no one that believes that statement would have a 348 or 409 based block. The hype for a 409 over a 348 is like a merit badge of waste (granted I have several 409's). Very few people make use of the extra cubes and big hp numbers can be had out of the 348. I didn't grow up in the generation when these were new, racing was hot between the Big Three and the Beach Boys had a song based on sounds from a 348. I grew up when these were dime a dozen and no one cared in the late 70's early 80's. Now they are getting a larger following because of the aftermarket helping supply parts allowing (in general) the older generations to bring these engines back to life with a little more reliable pep. Beach Boys have no effect on my generation (I like them but I'm a little odd) or the younger generations behind me who will buy a 348 and stroke them with more cubes than any factory 409 based engine ever was simply because its cheaper to get blocks. Guys like me that love the old school vibe are few and far between which really sucks but the numbers are growing thanks to the older generations passions about these engines and the aftermarket helping out. So lets all pitch our W motors and run 632ci BBC.
https://www.summitracing.com/parts/...pVK029mBXLq40y5w7SI8AS72aZBam0choCHiIQAvD_BwE

 

[Don Jacks]

I like the challange of making a small engine run quickly and reliablaly and on a budget.

 

[1964SuperStocker]

I like the challange of making a small engine run quickly and reliablaly and on a budget.

The aftermarket for these engines has come so far in the last few years giving just about anyone more options in what can be accomplished.

 

[427John]

I like the challange of making a small engine run quickly and reliablaly and on a budget.

And that's the key,while the statement there's no replacement for displacement is true(ie there's nothing a smaller BBC can do that a bigger BBC can't do better),once you get past a point cubic inches usually means cubic dollars,and while smaller engines can make lots of power the higher rpm's required to do it and the expensive parts needed to ,make it live at those rpm's also gets you into the cubic dollar scenario.I see the ~500hp range as more than adequate for most things you can do on the street if your being realistic and honest,and those power levels are absolutely obtainable with engines near their stock displacement and easily affordable for lots of people.But if money is no object,why stop at 632 we can all buy one of those 1000 ci engines and be street outlaws.

 

[boxerdog]

I like the challange of making a small engine run quickly and reliablaly and on a budget.

I'm with Don on this one, plus the "thrill of the hunt" wears off sometimes. It's too hard to find a good, reasonable, un-molested 409 block around here (at least for me) and really solid 655s are much easier.

 

[427John]

I'm with Don on this one, plus the "thrill of the hunt" wears off sometimes. It's too hard to find a good, reasonable, un-molested 409 block around here (at least for me) and really solid 655s are much easier.

Has anybody heard of anyone trying a longer than 4.0" crank in these blocks?Also are there any 348 block castings other than the ones cecil and scott spoke of that will bore to 4.25 or larger?

 

[1964SuperStocker]

Has anybody heard of anyone trying a longer than 4.0" crank in these blocks?Also are there any 348 block castings other than the ones cecil and scott spoke of that will bore to 4.25 or larger?

I would suggest starting a new thread on this question. We have talked about it before. I know getting 450+ci in a 348 seems possible but there are serious considerations to make about the oil pan area not having enough room to swing the counter weights/rod ends.

 

[Tooth]

I'm with Don on this one, plus the "thrill of the hunt" wears off sometimes. It's too hard to find a good, reasonable, un-molested 409 block around here (at least for me) and really solid 655s are much easier.

Dave, I too have noticed that a good 409 block is crazy high. That’s why I would prefer an aluminum block over an iron block. I’ve been talking to Bob and have bought a couple sets of his heads, timing chain roller lifters etc. by the time you make seven or 800 hp I would feel more comfortable with four bolt main caps. Just me. I’ve had big block Chevy two bolt mains been upwards of 700 hp and they don’t last forever. But the Cranks are available and are cheap the rods are cheaper and they’ll fit right into an aluminum block. I know the blocks are high but by the time you buy an iron block that’s 60 years old and do all the machine work and make it right for a high compression high horsepower engine I think you’re ahead to have an aluminum block. Just my thoughts! However I’m searching the junkyards where I used to grow up In hopes That I might find a few diamonds in the rough. For a street driven car I agree at 348 is the best way to go especially due to the cost. That’s why I have four 348’s now and only two 409’s.... And if Bob ever get somebody to finish the locating on his aluminum blocks I’m going to buy two! And I will have a 632.world blocks are out their too... Bob said right now they are in limbo...

 

[boxerdog]

Did Bob finish up any of the iron blocks? I thought they would be a great option, too.

 

[Don Jacks]

There are drop in 4.25 stroke cranks made but you'd better talk to Jack GIBBS because he's one of the few that can put them together and live.There aren't many 4.25 strokers in factory blocks for some reason.Before going out here and getting displacement crazy remember that your 60 plus year old castings have limits .

 

[Tooth]

I think Tim has started something! Because of his Dyno results I know I can get over 425 hp easily on a budget build. Parts are available and you can always step it up. Some people like to street race some people like to cruise. And I think Tim is giving me an idea what I can do with some of my 348’s The biggest hurdle I see is the 3.75 stroke crank. I just sent one off to Springfield Missouri and had the mains turned to 2.500 MOT and the rods cleaned up at at .010. This is a forged cross drilled 427 crank.( Curious to know where Tim got his crank). I have called and they sell a new four-inch stroker crank and keep them in stock. But the 3.75 they don’t stock and would be like 800 or $900 to build it. So I would say if you find a 3.75 Crank that’s in good shape you better pick it up. And by the way they magna flux it and ground mine for 225.00 the crank cost me 150.00 And the counterbalance and the thrust were ground by a friend for free Who has a CNC lathe. We are going to measure the 348 block for a 4.00 stroke.
Tim, Thanks for all the info that you have been contributing to the Thread!!!!!!!!!!!!! And I’m sure there’s plenty of people out there that’s already been through this but I haven’t seen it anywhere. This forum ROCKS!!!!!!! Talk to Bob and he said his engine bocks are in limbo right now, Trying to find somebody (GOOD) to locate all the holes and finish the blocks....

 

[Tim]

I think Tim has started something! Because of his Dyno results I know I can get over 425 hp easily on a budget build. Parts are available and you can always step it up. Some people like to street race some people like to cruise. And I think Tim is giving me an idea what I can do with some of my 348’s The biggest hurdle I see is the 3.75 stroke crank. I just sent one off to Springfield Missouri and had the mains turned to 2.500 MOT and the rods cleaned up at at .010. This is a forged cross drilled 427 crank.( Curious to know where Tim got his crank). I have called and they sell a new four-inch stroker crank and keep them in stock. But the 3.75 they don’t stock and would be like 800 or $900 to build it. So I would say if you find a 3.75 Crank that’s in good shape you better pick it up. And by the way they magna flux it and ground mine for 225.00 the crank cost me 150.00 And the counterbalance and the thrust were ground by a friend for free Who has a CNC lathe. We are going to measure the 348 block for a 4.00 stroke.
Tim, Thanks for all the info that you have been contributing to the Thread!!!!!!!!!!!!! And I’m sure there’s plenty of people out there that’s already been through this but I haven’t seen it anywhere. This forum ROCKS!!!!!!!

tooth I’m far from an engine builder and with the geniuses here I was able to pull it off. The crank is a stock 409 crank I got from Tom K here. It was checked and balanced and was ground 30/30. With all the right pieces all those 409 parts went in the block with no issues. Did all the bowl work on the heads myself and all the assembly(sometimes twice)! For the first time building an engine and one of the most finicky complicated ones I’m proud of it. Looks good and has everybody around here wondering what it is! Love this place 348-409 and the friends I’ve gained here

 

[Tooth]

Looks to me like you’ve got a good start on your engine building. And my 348 block came from Tom K. I wonder if he’s getting a kit back from people investing money off his parts? And I’ve got a couple of good 409 Cranks and rod sets. 380ci maybe the way to go...

 

[Don Jacks]

Bang for the buck Tooth use a 409 crank,6.385 rod and the Icon piston for the 4 inch stroke.his is what Tim has.Option 2 would be the 409 crank,the 409 rod and the 10.5 -1 Icon piston for the stock stroke 348 crank.This combo will push 11-1 which will require carefull cam consideration on pump gas and iron heads.