440 vrs RPM'S

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kocuda

kocuda

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Whats your opinion?
I have a well built 440, good Eagle bottom end, buillet timing gears, sold lifter cam, Harland and Sharp roller rockers, reworked Eddy heads, you know good stuff. Every thing is set up for a power band of 4500rpms to 8500rpms.
This motor pulls strong in the upper rpm range, but I'm old school and have all my rev protection set at 6800 rpms. The engine at that point still is pulling and reving strong!
Am I at the safe rpm range or could it be higher? I dont want to break it.
Need some feed back!!!!!!
 
Why do you want to spin it so high? Either you have an EXTREMELY large camshaft, or? Do you have aluminum rods? What about titanium valves? What about an oiling system? Can't understand why you want to go so high. how about a little more about your build.
 
More about the engine, the rods are h beam, valves are not titanium, the cam is pretty radical ( I dont have the specs with me right now. Oiling is Melling high volume pump, large pickup and large capacity pan with windage tray.
Its not that I want the high rpms, this engine was put together with this combo when I bought the car. I've had the engine all apart to insure it was assembled correctly.(had two blown head gaskets when I got it) has a 4500rpm converter and 456 gears.
I'm wanting others imput on a reasonable and fairly safe rpm range to be winding this engine out to when I feel the need, if you know what I mean!!
 
Read these articles and you,ll know why i chose milodon oiling. if landy says so its got to be sohttp://www.popularhotrodding.com/enginemasters/articles/bigblockshootout/0107phr_bbmopar/index.html
 
What exactly was done to the bottom end? Studs? Caps? Compression ratio? cam specs? anything done to heads? what diameter convertor? Tire diameter? Intake? Carb? What headers?
 
Thanks daredevil,
Did you install the external pump system? And what was your cost and the mods involved?
The more imput I'm getting from all of you, The more nervous I'm getting about even turning over 6500 rpms, should I be?
 
moper,
Stock main caps with studs, comp 12.5,sorry dont have the cam spec sheet with me, 9 inch converter,29.5 inch tire diameter, weiand team g intake,
quick fuel 850 carb, 2inch to 3.5 collector headers
 
What mph does it run now? Is the cam flat tappet or roller? How much work is in teh edelbrocks?
 
flat tappet cam, comp valve job, intake ports on heads smmothed matched to intake manifold. As for mph I've never had it to the strip, plans to trailer it there this summer in the works, just to see what it runs. Wish I was closer than a two and a half hour drive to the nearest strip.
 
kocuda, it sounds like you are probably correct in your rev limit. I would not wanna see what would happen beyond 7000 rpm. Dandy Dick Landy was one of the all-time greats when it comes to Mopars. He was the first to get his hands on a 68 SS Hemi car and made the first pass, a new record, 10.51 at 130 something (I think).
Like previously said, if he said so, it is true!
Dick Landy is in the record books and is a great piece of Mopar history.
I'll miss him but I'll never forget him.
http://www.dicklandy.com/

P.S. While Dick Landy is no longer with us, Larry Shepard is and his phone number is 330-644-2000.
Another man to talk to is Bob Mazzolini 951-787-8783
 
Thanks for all your input its most appreciated. I guess what I'm really asking for is, given what I have already described, what is a fairly safe upper rpm range?
 
kocuda said:
Thanks for all your input its most appreciated. I guess what I'm really asking for is, given what I have already described, what is a fairly safe upper rpm range?
Click to expand...

You got me thinking and I wanted to confirm my advise to ya so I called Bob and he agreed...no higher than 7200 at this point.
I told him you may be calling him and he said please do.
You really need to know what cam you have in there before calling him because otherwise, we're just assuming things...and that aint good!
 
Thanks Dave,
Soon as I can get my hands on the cam spec sheet (wont be home for two weeks) I will give him a call. Again thank-you
Ken
 
kocuda said:
Thanks Dave,
Soon as I can get my hands on the cam spec sheet (wont be home for two weeks) I will give him a call. Again thank-you
Ken
Click to expand...

If that thing is as nice as it looks in the pic....I am very jealous! :bootysha:
 
From what you've posted, I wouldnt take it as high as you do now. I doubt it's making power past 6K as it is. If the lower end has no oiling mods (impossible to see unless you really know what to look for...) and no main caps, plus heavy rods... I'd wager too high and you have cap walk already. I have revv'd my factory original lower end to 7200, but it doesnt make any power up there and it sure can't do it for very long.
 
My take is....If you built it to work up at 8500....Then it should work up at 8500 for so many runs as you built it for.....
But if your only going to work it to 6500 or 6800....Readjust the combonation..You might like it a little better.... Ya never know.


:salute:
 
think i paid around 500 for the pan,. pickup and the pump.and you need to block offthe internal pickup. thats covered in part 3 of the landy article.
 
racerhog said:
My take is....If you built it to work up at 8500....Then it should work up at 8500 for so many runs as you built it for.....
But if your only going to work it to 6500 or 6800....Readjust the combonation..You might like it a little better.... Ya never know.


:salute:
Click to expand...

if it has stock caps it wasnt built to live at 8500. in reality billet caps are softer to alow crank flex to keep main webs from breaking.gives it some give just like race gears are softer than street gears. when things are too confined they go boom.
 
Everybody is making great sense.
I tend to believe the best thing I could do is change the cam to something with a different power band than the 4500 to 8500 I have and probably the intake as well. If i went with a cam that made the most horsepower between lets say 3500 to 6500rpms, would my 4500 stall converter then become an issue?
 
changing power band will affect stall speed. too much is better than not enough. thats a lot of stall for the street
 
daredevil, You are sort of right.. factory caps will deflect in the center and pinch the bearings at the parting lines, causing cap walk. The bad harmonics this causes are partially absorbed by the main webbing structure, and the fasteners(bolts). A girdle splits the force over all the caps, and transfers it better to the entire block skirt, not just the webbing. So, the first upgrades are good internal balancing and the lightest parts you can afford that will work for you. The next step is replacing the bolts with studs that clamp the caps more, and limit the walk. However, these transmit more harmonics to the webbing. Next up grade is billet steel caps, which will not deflect, and combined with the studs, place all the force of the harmonics to the webbing. Most RB blocks at the 550hp level and up have a short life expectancy because of webbing failures. The last way to address this is either aluminum caps or aluminum rods. Those have a finite life span, but act as shock absorbers taking stress out of the webbing, and in the rods' case, taking weight off the reciprocating mass.
 
In response to the rpm capability... as I said, if an engine doesnt make power above X rpm, it's senseless to push it there. Unless that flat tappet is HUGE, there is no way it's making power above 6K on basically stock Edelbrocks and that intake. It sounds like a healthy street engine. So racey stalls will hurt it, not help. The best bet, would be to snoop and get the real figures for static compression and flow, spec a camshaft that gets the engine to do what you want it to, and then order a convertor to match. If your peak torque is at 4K, then a 4500 convertor is a waste. The flash stall speed should be about 200 rpm lower than the engine's torque peak andd have the least slip in high gear you can get. The gears for a strip car should put the engine at just past it's horsepower peak in 3rd gear at the stripe. For a street car, the gears should be mandated by usage. Local=more gear, highway=less gear.
 
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