Rebuilt Transmission - RPM Question

[mccurdy]

So i just had my transmission rebuilt this past week, and I've noticed something with the RPM band.

Now, it could be since i haven't driven the car consistantly in a few months, but I don't think so.

I've noticed the RPM's are really high for the speed I'm going (Geared low?).

In 5th gear @ 70 MPH im almost at 3,750 - 4,000 RPM's. Now, I've raced my car before, and i know 4k RPM is really high for 70 MPH in 5th gear.

4th gear seems a bit high too (as for the RPM's) for the MPH i'm going.

2nd gear I clocked it at about 4k RPM for 30 MPH. This doesn't seem that far off from normal, but still seems i can't pull the speeds i once could in the same gears.


Does anyone have a list of the 2g RPM speeds for MPH or some sort of conversion formula? I don't have any Cam work done. Just clutch and aluminum flywheel. While i know aluminum flywheel helps the RPM's climb quicker, it sure as shit won't do what i'm noticing.

Any help is really appreciated as i need to know if i should take the car back to the transmission shop to have them inspect exactly what gears were installed..

Thanks!

 

[SrKegler]

4k rpm's should put you about 90 mph in 5th. Check out jacks trans. Don't know what happened in your case.

200 MPH DSM

 

[mccurdy]

Crap. So being at like 3,750 at 70 MPH is definately not right then?

 

[xreaction122]

The gearing seems to be too short. I can imagine you going through gears like a sti

 

[mccurdy]

So i called the shop telling them that 4th and 5th feel short. He was not happy and I don't think believes me. Regardless, being at near 4,700 RPM's in 5th going 90 is bad for the engine and gas mileage. At that rate, i'd top out at like 120!

This won't stand.

If anyone has any other coments, im all ears.

 

[rEclipserGST]

So i called the shop telling them that 4th and 5th feel short. He was not happy and I don't think believes me. Regardless, being at near 4,700 RPM's in 5th going 90 is bad for the engine and gas mileage. At that rate, i'd top out at like 120!

This won't stand.

If anyone has any other comments, I'm all ears.

Uh drive it over there and Show him? Take your receipt and someone who can intimidate them. That should give a good outcome.

 

[cbrfrenzie]

If you have a friend with a similar car you could compare speeds and RPM's, then bring him and his car with you to the shop and put it in their face!

 

[mccurdy]

I checked the RPM speeds from Jackstransmissions.com

Stock 5th gear is like 3k RPM for 70 MPH. I'm currently around 3,750 RPM for 70 MPH. So that is hopefully proof enough. I got a buddy who's girl has a stock GST. I'll drive her car and confirm for sure.

Thanks guys