explorer 5.0l redline

[Big Slim]

i was wondering what is the explorer 5.0 redline? would headers, intake or coils change that? these are the upgrades i have. or is cam and heads the only thing that would increase it? not realy planning on those type of changes. i am asking because im looking into a custom tachometer from speedhut. the explorer tach only goes to 6k so that is what i was thinking so i could get some better resolution than the 8k tach. then maybe adding some red bars for redline and a bronco logo. but wanted to get redline it in the right spot. from the power curves it hit the peaks by 4k. Something like this.

 

[pcf_mark]

It is not going to break at 5k but it is also done making power at 4300 rpm.

https://www.automobile-catalog.com/...xlt_4wd_5_0l_efi_v-8_automatic.html#gsc.tab=0

 

[DirtDonk]

The max rpm/redline is not just about breathing either. It's also about what will fail to fully function, or even break first.
You can have a wide open exhaust and a great cam, but if the valve springs are not up to it, you might get valve float at 6,000 or so. Probably even less if they are old and tired.
Bearings, rods and rocker arms are usually pretty safe at least for slightly higher rpms, but only for so long. Valvetrain stability can make the difference in a clean 7,000 rpm run, or a fully trashed engine because the rocker studs pulled out, the pushrods bent, a valve guide broke, a valve bent and hit a piston, connecting rod bent or broken, or even tossed itself and it's piston through the side of the engine block!
It doesn't happen all that often maybe, but you get the picture...

If the engine is remaining mostly stock, a 6k tach with a 5500 red zone is probably perfect.
I personally always wondered why high-performance tach manufacturers didn't also just add a 7k version for those of us compromisers in the middle.
Your idea of higher resolution is very valid. Nice tach in the pic too, but I'd prefer to see the knob at the bottom and the numbers skewed a little more clockwise.
I just like to see the more usable rpm range, such as between the 3 and 4 numbers, towards the top/middle.

Paul

 

[Timmy390]

EFI = whatever you set your limiter at. Same with MSD ignition boxes. I've buzzed mine a couple times on both my Bronco and my Shelby. Honestly on both I was way too busy to notice the RPM's.

The real answer is "just before valve float" and that depends on cam/setup but really there is no reason to go that high. Once max HP/Torque is reached, more is not better. Both are dropping at that point.....Only bad things can happen after that.

Most cams peter out around 5K to 5500

Tim

 

[bmc69]

The solid-lifter 302 in my EB race truck apparently didn't have a "red line". Peak HP was was at 7300 but I routinely buzzed it so that the needle on the 8K tach dial would go on past to hit the "zero " peg...which I estimated to be roughly 9000 RPM.

Your experiences may vary.

 

[Timmy390]

The solid-lifter 302 in my EB race truck apparently didn't have a "red line". Peak HP was was at 7300 but I routinely buzzed it so that the needle on the 8K tach dial would go on past to hit the "zero " peg...which I estimated to be roughly 9000 RPM.

Your experiences may vary.

That's how you put window in blocks..... LOL

Tim

 

[lars]

Worth noting is that OEM Explorer valve springs stop being happy by 5000 rpm or less. Add a cam with more lift and the margin gets even thinner, AKA broken valve springs. I've broken some on GT40-P heads. Plenty of easily installed aftermarket options, no need to remove heads to replace.

 

[bmc69]

That's how you put window in blocks..... LOL

Tim

Mexican block...well prepped. Never ventilated one yet!

 

[Big Slim]

maybe the tach with the shift lights would not need to add redline artwork as the lights could be the indicator. and could adjust lights at any time if valve train or heads are is updated. i had my computer tuned at efidynotuning and he said the redline is set at 6500. sounds like i still dont want to go that high with stockish motor with supposedly 80k ish miles.
but i am leaning more towards the non-shifter lighted version. This concept so far. Needs refining.

 

[Broncobowsher]

Typical late model roller cam small block goes into a yellow line a little over 5000 RPM. My understanding that was max sustained speed. Redline is at the high end of 5000 and the ECM fuel cut 6250.

Typically valve train stability is the first limitation, that typically happens past the peak power and the output is dropping off anyway. In the old days it was often the points would start bouncing and that would be enough to limit RPM. I've had built 302 that had the limiter set to 7000. But that was pointless as the power peaked in the 5000s.

Most of the time when the bottom end lets loose it is an oiling issue and not a material strength issue. Oil pumps and oil ports have there own limitations as well.

 

[BigBronco16]

What is the redline of an original 302 from 73?

 

[Broncobowsher]

What is the redline of an original 302 from 73?

I've never seen one published. Usually the valve springs have lost stability somewhere in the 4000 RPM range, might make it to 5000.

I have a small block boat motor and I see 4200-4400 RPM listed. Which is probably max speed since my older Y-block states 4000 with ideal cruise at about 3300. But that is also a boat motor and setup to run as such.

 

[DirtDonk]

They probably rarely, if ever listed it for trucks. The only ones with a published redline would’ve been those with a factory tach maybe, such as a performance mustang perhaps.
But in 73 I’m not sure there was a performance mustang with a standard 302. Might still have been available with a tachometer, however, which may or may not have showed a yellow and red line. But every tach that I ever saw from back in the 60s and 70s that had a red line posted, except for Corvettes, was at 5500 RPM.
That was for V six and V eight engines.
Probably a Hi-po 289, and a Boss 302, and probably the others with specialty engines such as boss 429, could’ve been higher.
I’ve seen Corvette tachometers with anywhere from 5500 to 7500 RPM red lines.
I don’t know if the 7500 it was strictly for the L88, the ZL1, or maybe one of the LT-1 350s.
Just that I’ve seen them.

If the Chevelle had a tachometer option, and an LS-7 it might have had a higher rpm redline also.
Maybe…

But standard engines like we have in pick up trucks, and Broncos would certainly have had no specialty equipment that would’ve allowed them to rev higher than necessary.
My 71 302 would not rev past 5200, so there was likely no reason to publish an anemic redline.
Especially in a vehicle with no option for a tachometer.

 

[BigBronco16]

That fits with my real life experience...about 4500 is all it has. Thanks to all.

 

[DirtDonk]

This concept so far. Needs refining.

Make the horse's butt yellow and the horse's leg red!

Paul

 

[sprdv1]

maybe the tach with the shift lights would not need to add redline artwork as the lights could be the indicator. and could adjust lights at any time if valve train or heads are is updated. i had my computer tuned at efidynotuning and he said the redline is set at 6500. sounds like i still dont want to go that high with stockish motor with supposedly 80k ish miles.
but i am leaning more towards the non-shifter lighted version. This concept so far. Needs refining.

Like it...

 

[sprdv1]

Make the horse's butt yellow and the horse's leg red!

make it stand out for sure