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Safe Rev Limit for 440?

Posted By: wingman

Safe Rev Limit for 440? - 04/11/11 12:04 AM

I know this question involves a ton of variables, and probably some opinion, but...

The MSD ignition 6AL box I got free only came with a 7000 pill, and I know that is too high.

The motor is a 71 block, 9.5 compression with mostly stock internals except for forged .30 over TRW pistons and good quality valves. Crank and rods appear to be stock.

I don't race the car, I just use it for cruising and fiddling around town. But with the steep gears my car has, fairly loose converter, and manual valve body, I'm afraid I'm going to miss a shift someday and be sorry.

What would be a good pill (or set of pills) to get that will keep the motor safe--but not too safe?
Posted By: imfixinmopars426

Re: Safe Rev Limit for 440? - 04/11/11 12:23 AM

std ly rod,heavy trw...=5500. or will have problems,imho...
Posted By: dhkennedy

Re: Safe Rev Limit for 440? - 04/11/11 12:28 AM

I had a 69 six pac in a 79 RC with a 5500 rev chip and that was spinning the 35s fast in the mud hitting the limit. Now I have a 75 D100 with a 78 HP that is Fast EZ-EFI limit set to 4500 and have hit it in second gear and thought that was too high for an engine that has never pistons out of the block.
Posted By: gch

Re: Safe Rev Limit for 440? - 04/11/11 01:28 AM

You never mentioned what cam you are running.What rpm do you shift at?I would put a 6000rpm pill in it and call it a day.
Posted By: Junky

Re: Safe Rev Limit for 440? - 04/11/11 01:52 AM

Quote:

You never mentioned what cam you are running.What rpm do you shift at?I would put a 6000rpm pill in it and call it a day.


I shift at 6000 and have my limiter set at 6300. I can dial mine. I don't want to run up against it. So if you're shifting at 5500 to 5800, a 6000 pill should do the trick.
Posted By: DaytonaTurbo

Re: Safe Rev Limit for 440? - 04/11/11 02:06 AM

I would also rev it to 6000 without worrying.
Posted By: MoparforLife

Re: Safe Rev Limit for 440? - 04/11/11 02:15 AM

Quote:

I would also rev it to 6000 without worrying.


It may stay together and may or may not even float the valves in a stock 440 at 6000 but why twist it that far when it will peak long before that and you will be far better off shifting earlier. (and easier on the motor too)
Posted By: DaytonaTurbo

Re: Safe Rev Limit for 440? - 04/11/11 03:16 AM

Quote:

Quote:

I would also rev it to 6000 without worrying.


It may stay together and may or may not even float the valves in a stock 440 at 6000 but why twist it that far when it will peak long before that and you will be far better off shifting earlier. (and easier on the motor too)



The op hasn't said what he's got for cam and head flow, but I agree that if it's out of breath long before 6000 there's no point in taking it that high. But if it was peaking out higher in the rpm range I wouldn't sweat taking it to 6k.
Posted By: 383man

Re: Safe Rev Limit for 440? - 04/11/11 04:46 AM

I have a stock bottom end with KB pistons and I shift at 6200. Been running it like that for years. Ron
Posted By: quickd100

Re: Safe Rev Limit for 440? - 04/11/11 11:15 AM

I reved my stock bottom end 440's to 62-6300 for years and hundreds of passes. I did use good rod bolts though. Dave
Posted By: Pyper70

Re: Safe Rev Limit for 440? - 04/11/11 01:13 PM

Not to hijack...but do they make a 1500 pill or a 2000 pill that you can put in the MSD box....and render the engine useless when you park it somewhere....If you cant get past a low rpm....thats a pretty good theft deterrent device OR if you have kids in the house...Latter doesnt apply to me.
Posted By: gch

Re: Safe Rev Limit for 440? - 04/11/11 03:17 PM

They make low rpm pills.YOu should be able to find one for 3000rpm.
Posted By: Pacnorthcuda

Re: Safe Rev Limit for 440? - 04/11/11 03:28 PM

Quote:

Not to hijack...but do they make a 1500 pill or a 2000 pill that you can put in the MSD box....and render the engine useless when you park it somewhere....If you cant get past a low rpm....thats a pretty good theft deterrent device OR if you have kids in the house...Latter doesnt apply to me.



Why not just unplug the distributor connection or pull the coil wire?
Posted By: Cudajon

Re: Safe Rev Limit for 440? - 04/11/11 03:52 PM

Mines a stick so I run a 6200 limiter and try to shift at 6000. Hits the limiter every once in a while. 494 - Muscle motors stroker kit, their bracket master heads. Going aluminum whenever I can figure which ones to use, botom end is stock with ARP studs.
Posted By: therocks

Re: Safe Rev Limit for 440? - 04/11/11 08:49 PM

I have my limiter set at 6800 on my 440.Its been well over that though.Still pulls strong when I shift.All ARP lower with studs.Been doing it for 5 years and no problems.Stockish 440 will probally be done at 5600 or less.Rocky
Posted By: Pyper70

Re: Safe Rev Limit for 440? - 04/11/11 09:45 PM

Quote:

Quote:

Not to hijack...but do they make a 1500 pill or a 2000 pill that you can put in the MSD box....and render the engine useless when you park it somewhere....If you cant get past a low rpm....thats a pretty good theft deterrent device OR if you have kids in the house...Latter doesnt apply to me.



Why not just unplug the distributor connection or pull the coil wire?



Then I have to pop the hood...I have my box mounted right on top of the center console....directly behind my ashtray...I can stick my hand under there and the pill is right there....
Posted By: terzmo

Re: Safe Rev Limit for 440? - 04/11/11 10:07 PM

6000 for a stock crank ....5300 for a stroker crank...
Posted By: wingman

Re: Safe Rev Limit for 440? - 04/11/11 10:28 PM

Thanks for all the input guys!
Posted By: Anonymous

Re: Safe Rev Limit for 440? - 04/11/11 11:20 PM

Quote:

Quote:

Quote:

Not to hijack...but do they make a 1500 pill or a 2000 pill that you can put in the MSD box....and render the engine useless when you park it somewhere....If you cant get past a low rpm....thats a pretty good theft deterrent device OR if you have kids in the house...Latter doesnt apply to me.



Why not just unplug the distributor connection or pull the coil wire?



Then I have to pop the hood...I have my box mounted right on top of the center console....directly behind my ashtray...I can stick my hand under there and the pill is right there....



I put the 3,000 chip in the 'Cuda when the wife wanted to drive it to the store one time. It took her a while to tell me that she thought she broke it! LOL!
Posted By: Pacnorthcuda

Re: Safe Rev Limit for 440? - 04/11/11 11:36 PM

100 RPM less than when it lets go.
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