8k rpm ...

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65-440

65-440

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Ok, don't beat me up on this one. No I don't race, I know it's completely impractical .... thinking of rebuilding the engine in my 70 340 swinger in the near future. Will be putting the #'s matching engine in the corner of the garage, I have a complete stock bore 71 340 that I'd build. My problem, I want 8k rpm. Want to build a fun, high revving engine for around town pleasure. Not sure why 8k stands out to me but it just does . My question is, how attainable is this and how much work are we talking about so I don't worry about sending shrapnel outside the engine block everytime I get on it ?
 
I took mine to 7600 many times with no problems. basically stock bottom end.
 
It's attainable. If it was ME, I'd stick with the stock stroke. It's gonna need really a good cylinder head, too. BIG intake, BIG carburetor and BIG headers.
 
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180,000 psi rod bolts (ARP, Pioneer, Milodon) and a cam and intake that will support that. Stock rods are pretty good. I like the Holley Strip Dominator intake. You build for 8k and your gonna be stuck in the mud at low RPM's unless you got a 4.3+ rear gear. Put an RV cam in it and youll run out of steam at 5000. Your power band can only be so wide. Build it high or build it low. Solid cam will extend the power band a little. My friend drove his mom's 4cyl baby Blazer around in high school and that had a very torquey motor, would hole shot all the V8's but would get passed right after the other crosswalk, after it hit 50, it hit a wall motor wise.
 
Sorry OP. You need to get your head examined. I don't know who else claims to have done it, but 8000 RPM and making power doing it requires more than just stock junk.

Don't bother. BTDT.

And if you think I'm wrong, go look at the thread here about the oiling thread on ST.
 
yellow rose said:
Sorry OP. You need to get your head examined. I don't know who else claims to have done it, but 8000 RPM and making power doing it requires more than just stock junk.

Don't bother. BTDT.

And if you think I'm wrong, go look at the thread here about the oiling thread on ST.
Click to expand...
My head is just fine thanks for worrying about me though. I pretty much already assumed stock parts would not do it without carnage at some point. I know there's a lot that goes into it, was just trying to get some specifics from those that have done it successfully
 
My solid lifter340 pulls good to 7200... but after that I noses over hard...for the street it’s not great. In fact the 360 that was in the car before that fell off at 5500 was much better...
 
@AJ/FormS needs to step in and do some math to let you know how fast you will be going at the top of first gear at 8000 rpm.
:lol::BangHead::BangHead::BangHead:
65-440 said:
Ok, don't beat me up on this one. No I don't race, I know it's completely impractical .... thinking of rebuilding the engine in my 70 340 swinger in the near future. Will be putting the #'s matching engine in the corner of the garage, I have a complete stock bore 71 340 that I'd build. My problem, I want 8k rpm. Want to build a fun, high revving engine for around town pleasure. Not sure why 8k stands out to me but it just does . My question is, how attainable is this and how much work are we talking about so I don't worry about sending shrapnel outside the engine block everytime I get on it ?
Click to expand...
 
65-440 said:
Ok, don't beat me up on this one. No I don't race, I know it's completely impractical .... thinking of rebuilding the engine in my 70 340 swinger in the near future. Will be putting the #'s matching engine in the corner of the garage, I have a complete stock bore 71 340 that I'd build. My problem, I want 8k rpm. Want to build a fun, high revving engine for around town pleasure. Not sure why 8k stands out to me but it just does . My question is, how attainable is this and how much work are we talking about so I don't worry about sending shrapnel outside the engine block everytime I get on it ?
Click to expand...

How much power are you wanting?
 
ou812 said:
How much power are you wanting?
Click to expand...
Don't have a number in mind honestly, just want it to hold together !
This all stems from a guy near me with a 327/4spd 55 Chevy. He drives the **** out of his car, shifts at 8k everytime he drives it. Sounds amazing!
 
O.K. My 340 I built in 1977 and on a major budget just out of high school. I had been collecting 340 parts and had a lot of low mileage parts. I had a perfect std bore 69 block, a perfect crank, and with the help of a friend that was a engineer at Chrysler and a racer I put together a nice 340. It had full groove clevite micro babbit mains, micro babbit rod bearings, stock crank, my buddy did the rods opened up the big end so it would have .0035 clearance then cut .001 off the caps, we had .0025 top to bottom on the rod and .0035 on the sides. Now you can just buy bearings with more side clearance but not back then. 10.5 :1 pistons std bore, 400 grit finish, moly rings .040 + 5 file fit Chevy rings, 1/3 the price of mopar rings. X heads pocket ported with a full radius seats, my buddy made his own stones on a fixture he made at Chrysler. Stock 2.02 1.60 valves, dual valve springs, MP cam .572 .296 mechanical with crane ductile rockers, Hooker 1 7/8 super comp headers, MP mechanical 6 pack carbs. Ran 11.84 114.9 MPH in a 64 Barracuda shifting at 7600 RPM
727 Turbo Action VB, 4200 stall TA converter, 5:13 Dana 60 w/spool

img491.jpg


img492.jpg
 
This is more about the oiling system.
Everything else is easy to obtain.
 
65-440 said:
Don't have a number in mind honestly, just want it to hold together !
This all stems from a guy near me with a 327/4spd 55 Chevy. He drives the **** out of his car, shifts at 8k everytime he drives it. Sounds amazing!
Click to expand...
Contact "Mr P Body" on Moparts he's known for typical 8K passes in his drag car.
 
brian6pac said:
O.K. My 340 I built in 1977 and on a major budget just out of high school. I had been collecting 340 parts and had a lot of low mileage parts. I had a perfect std bore 69 block, a perfect crank, and with the help of a friend that was a engineer at Chrysler and a racer I put together a nice 340. It had full groove clevite micro babbit mains, micro babbit rod bearings, stock crank, my buddy did the rods opened up the big end so it would have .0035 clearance then cut .001 off the caps, we had .0025 top to bottom on the rod and .0035 on the sides. Now you can just buy bearings with more side clearance but not back then. 10.5 :1 pistons std bore, 400 grit finish, moly rings .040 + 5 file fit Chevy rings, 1/3 the price of mopar rings. X heads pocket ported with a full radius seats, my buddy made his own stones on a fixture he made at Chrysler. Stock 2.02 1.60 valves, dual valve springs, MP cam .572 .296 mechanical with crane ductile rockers, Hooker 1 7/8 super comp headers, MP mechanical 6 pack carbs. Ran 11.84 114.9 MPH in a 64 Barracuda shifting at 7600 RPM
727 Turbo Action VB, 4200 stall TA converter, 5:13 Dana 60 w/spool

View attachment 1715428025

View attachment 1715428026
Click to expand...


I can say the tach was probably off by 150-200 RPM low (they always are...sent my Autometer dual range tach because it was acting wonky and it was off by 350 RPM at 7500 which meant it was really 7150 RPM) and there is a mile of difference between 7500 and 8000 RPM.

And there is a big difference just getting enough spring to make 8000 RPM. It another deal to make power up there.


Edit: forgot to mention the Autogage tach I replaced with the dual range tach was off by about 125 RPM at 1000 RPM. I could check that with my ignition box.

Most tachs are off.
 
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65-440 said:
Don't have a number in mind honestly, just want it to hold together !
This all stems from a guy near me with a 327/4spd 55 Chevy. He drives the **** out of his car, shifts at 8k everytime he drives it. Sounds amazing!
Click to expand...


Tell him to have his tach checked. I'd bet it's wrong.

And a SBC isn't a SBM.

Like I said, BTDT and have the scars to prove it. You need at least an X block or better. Period.

You need to fix the oiling system and every book ever written, every tech article ever published is wrong. Dead wrong. You ain't going to fix that junk oil in system with a grinder, a drill and tap and some tubing.

I won't even get into how you'd ever get the valve train anywhere near stable enough with a W2-5 style rocker system.

It goes on and on. You won't be running a spur gear pump. You'll have a gerotor pump. That takes a HUGE pickup to feed the pump at that RPM.

At that RPM you just about need to block off the internal bypass in the pump and move it outside the pan. And then you have to plumb it.

And you still haven't fixed the oil timing issue yet.

I hate to say it, but if you think you want that kind of RPM, go get a SBC and a tach that has been corrected.

Best of luck.
 
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rumblefish360 said:
This is more about the oiling system.
Everything else is easy to obtain.
Click to expand...

Thanks Rumble
I guess I forgot the most important part, The oil pump was a HV HP melling that was fitted to the cap and all oil passages cleaned up with long drill bits, opened up about .010 - .015" not much but made sure they were straight through clean, no burrs, rounded all corners that needed it. It had a Milidon pump cover with a 1/2" pick up out the bottom straight down to the bottom of a custom pan with 2 trap doors and baffles, also a custom windage tray, held 7 qts with 1" cut off the dip stick tube so the oil level was 1" lower in the pan. That's about it, no crossover tube, no blocked or restricted passages, I ran this motor on the street and the track for probably 15,000 miles in 30 years had it apart at least 6 times about every 5 years and it looked like new every time. I had the motor in my AAR when I sold it and it still had the same bearings that I put in it in 1977. Here is a picture of the motor I took it out of the AAR to put in new freeze plugs they rusted out over all the years.

100-0030_IMG.JPG
 
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brian6pac said:
Thanks Rumble
I guess I forgot the most important part, The oil pump was a HV HP melling that was fitted to the cap and all oil passages cleaned up with long drill bits, opened up about .010 - .015" not much but made sure they were straight through clean, no burrs, rounded all corners that needed it. It had a Milidon pump cover with a 1/2" pick up out the bottom straight down to the bottom of a custom pan with 2 trap doors and baffles, held 7 qts with 1" cut off the dip stick tube so the oil level was 1" lower in the pan. That's about it, no crossover tube, no blocked or restricted passages, I ran this motor on the street and the track for probably 15,000 miles in 30 years had it apart at least 6 times about every 5 years and it looked like new every time. I had the motor in my AAR when I sold it and it still had the same bearings that I put in it in 1977. Here is a picture of the motor I took it out of the AAR to put in new freeze plugs they rusted out over all the years.

View attachment 1715428029
Click to expand...


If you had that pan (which is now about impossible to find and I have two of them...one with a 1 inch static pick up and the other with the swinging pick up) then you had the 1 inch pick up tube. That's a massive help right there. A 1/2 inch pick up can't supply that pump much past 7000 RPM without serious issues.

So that was a big deal.
 
yellow rose said:
I can say the tach was probably off by 150-200 RPM low (they always are...sent my Autometer dual range tach because it was acting wonky and it was off by 350 RPM at 7500 which meant it was really 7150 RPM) and there is a mile of difference between 7500 and 8000 RPM.

And there is a big difference just getting enough spring to make 8000 RPM. It another deal to make power up there.


Edit: forgot to mention the Autogage tach I replaced with the dual range tach was off by about 125 RPM at 1000 RPM. I could check that with my ignition box.

Most tachs are off.
Click to expand...

Jones mechanical tach, had it tested when I bought it, it was spot on.
 
Damn yellow rose, sounds like you're convinced these engines aren't worth the trouble for high rpms .....
 
yellow rose said:
I can say the tach was probably off by 150-200 RPM low (they always are...sent my Autometer dual range tach because it was acting wonky and it was off by 350 RPM at 7500 which meant it was really 7150 RPM) and there is a mile of difference between 7500 and 8000 RPM.

And there is a big difference just getting enough spring to make 8000 RPM. It another deal to make power up there.


Edit: forgot to mention the Autogage tach I replaced with the dual range tach was off by about 125 RPM at 1000 RPM. I could check that with my ignition box.

Most tachs are off.
Click to expand...
My tachs always read 150 or so higher than what the motor actually rpm'd. Thing i never checked was if and how much the spread grew as the rpm climbed.
If i set it 850 rpm @ idle,it showed just under 1000 rpm
 
yellow rose said:
If you had that pan (which is now about impossible to find and I have two of them...one with a 1 inch static pick up and the other with the swinging pick up) then you had the 1 inch pick up tube. That's a massive help right there. A 1/2 inch pick up can't supply that pump much past 7000 RPM without serious issues.

So that was a big deal.
Click to expand...

It was just like this one and I still have a new cover some where, one was a conversion from std pump to HV and used a std pump housing and the cover was cut so the long rotor would fit, I had a flat cover that bolted on a HV housing. Now that you said that I think it was about 3/4" I.D. on the tube.

20180929_144536.jpg
 
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