I hope I didn't over rev my motor?

[ravv 67]

I recently put in a 302 in my fastback. Produces about 385 hp at the fly.
Well, I was showing off my car to a friend and I went to 90mph with a C-4.
Do you think I might of damaged the motor. The rear has a 3:55?
I'm asking because I heard the tone of the exhaust changed. Once I took the foot of the pedal I no longer heard the noise. I'm kind of kicking myself.

 

[dennis112]

90 mph is nothing with your combination--unless you were holding it in 1st gear. . . . . . . About 4100 rpm with 26" tires in 3rd gear

 

[ratio411]

Try 110 mph with 4.11s and get back to me...

 

[rbohm]

try 60 in first gear. even with 2.80 gears that is almost 6200 rpm.

 

[DJCarbine]

try 60 in first gear. even with 2.80 gears that is almost 6200 rpm.

I remember when I had the old 3 speed and 2.80 gears, I could stay in first the whole onramp to get on the highway

 

[rbohm]

I remember when I had the old 3 speed and 2.80 gears, I could stay in first the whole onramp to get on the highway

yeah, too bad when the stang gets the T5 with 3.55 gears i wont be able to hold it that high.

 

[BornInAFord]

You probably don't "floor" it that often. That may be the sound of the resonance with all 4 barrels fully open. If you go to youtube and search for "dyno" and "mustang" or similar, you'll hear the same thing. You go along fine until you reach around 2K rpm in high gear, then floor it. You'll hear the difference.

 

[DK832]

90mph - hehehehe This shot is from the I95. Toploader and 3.70 gears - look at the RPMs and do the math. The stupidest thing was to let go with one hand to take the picture.

 

[ravv 67]

I don't have a tach which is why I was concerned. It's just that the tone changed from a great sounding exhaust to something like a raspy glasspack.

Well I'm glad nothing went wrong and that I gave some of you guys a good chuckle.

 

[CraigMBA]

90mph - hehehehe This shot is from the I95. Toploader and 3.70 gears - look at the RPMs and do the math. The stupidest thing was to let go with one hand to take the picture.

I floated the valves on mine in 4th with a T-5 and 3.55 gears once. Scared the snot out of me at a 120+.

Can't quite do that in So Cal.

 

[65mistress]

As long as you don't hear a loud clunk or bang, then the strange noise, you should be alright.

 

[BullittStangV8]

I floated a valve. It was followed by some clunking and the car turning off. Bent a valve and cracked a piston. BUT after it happened i had a 7 cylinder car.

 

[ratio411]

I don't have a tach which is why I was concerned. It's just that the tone changed from a great sounding exhaust to something like a raspy glasspack.

Well I'm glad nothing went wrong and that I gave some of you guys a good chuckle.

You could have floated the valves.
If your valve springs can't handle the rpm you were doing, they will lose control of the valvetrain and change the entire sound and demeaner of your car.
Can scare you if you don't know what it is.
However, it almost never hurts anything, unless of course your valve springs can actually rev higher than the rest of the parts in your engine.
I always considered it a mechanical rev limiter... because float has saved me from blowing things up on missed shifts and such.

Edit:
Another consideration... running out of fuel.
Right now my Holley's floats are set too low.
The car runs fine around town, but when I get on the highway it runs out of fuel intermittently when I get over 70 mph for longer than about 1 minute. Kinda gets rough, raspy, pops some, falls on it's face if you keep trying to push it.
Actually, it could be the stock fuel pump I have on the engine in question now that I think about it.
I need to get around to checking the float level darn it...

 

[Jimmys66]

As long as you don't hear a loud clunk or bang, then the strange noise, you should be alright.

Is this coming from "personal experiance"?

 

[SL 1993 R]

it wasn't an over rev issue. I had my built 289 with a 4 speed top loader turning 7300 with 4.11 gears going into turn one at Willow Springs, right at 150mph..

 

[Rusty67]

If the motor still runs fine but the hole thing sounds different perminently I doubt it is a problem with the power plant. What kind of mufflers are you running ? Maybe you blew out the core in yer mufflers and now they sound all crappy.

 

[SoCalCruising]

SL 1993 R : your tire would be nearly 30" tall to do that. I'm very tempted to call BS on that one. Sure your speedo was correct?

 

[65mistress]

Is this coming from "personal experiance"?

Umm... no...


I was luckier than most, CLUNK BANG (there went the 64 1/2 non synchro 3 speed)

BANG rattle-rattle-rattle CLUNK (there goes the front U joint and drive shaft)

Those were really the only 2 instances, and they were many many moons apart.

 

[Dugan]

i have a 67 289 with 5.26 gears in it and a c4 tranny, what would my redline be????

 

[HistoricMustang]

I recently put in a 302 in my fastback. Produces about 385 hp at the fly.
Well, I was showing off my car to a friend and I went to 90mph with a C-4.
Do you think I might of damaged the motor. The rear has a 3:55?
I'm asking because I heard the tone of the exhaust changed. Once I took the foot of the pedal I no longer heard the noise. I'm kind of kicking myself.

If you were not on track you should be kicking yourself!

HistoricMustang