Max RPM / redline for '72 258

Can't seem to find an accurate #

I'm putting in an MSD system with plug in RPM chips. I want to get one about 200rpm lower than MAX (has a built in RPM limiter to not allow you to over rev.

 

Peak HP at 3500 rpm - no point in going much faster than that. What's the lowest RPM you can pick?

We've discussed this before - search the forum if you want more.

 

Lowest RPM module is 3000rpm. They do have an adjustable RPM module you can set a range from 1000 to 3000.

They bump the rpm range by 200 on both even and odd rpms (3000,3200, 3100,3300. Can only get them in even or odd kits)

I got a great deal on a brand new MSD electronic distributor for the 258.

I did see the max HP @3500 spec, but figured the the max RPM would be a tab bit higher.

 

I don't think a 'redline' as such is very meaningful for most factory engines from this era. These engines are all through (power-wise) by the time you reach a speed that will possibly damage the engine. Race cars will rev higher than is safe for them to go - power is basically torque times rpm, so if the torque curve is flat, the race car engine makes more power the faster it goes. It's tempting for racers to test the limits of the equipment, so some kind of limiter could keep the engine from being damaged in case of too much enthusiasm.

I think a safe limit for a 258 in good condition is probably about 5000 or 5500, but unless it's hopped up, you don't gain anything by revving that high. You would be conservative by picking a 4000 or 4500 limit, but I doubt you'll ever have the occasion to test it.

hth!

 

5000 is a safe number. You don't want to set it too low. If you are in a hole and have to get after it to make it through but the rev limiter is set at 3500 you are gonna be pi$$ed! 5000 will not hurt a sound engine. He!! my stroker 409 in my 62 Chev has buried a 8000 tach! Not on purpose, but it has happened. A rev limiter at anything less than 5000 and you will suffer.