high rpm on freeway??

[smartcarkiller]

When I had it on a dyno the machine said my speedo is 7mph slow. I feel like its more than that but When I am cruising down the freeway under light conditions, I usually travel with the flow of the fast lane and its usually about 70 average, at that point my speedo is at about 63ish+-.

 

[folkenheath]

OK, so there is something going on then. Either your converter or your trans or your tach is off, but you are saying you believe the tach is close. And if your trans was slipping that bad the fluid would be burnt. How is the fluid?

What exact converter do you have?

Also, FYI, your speedo will be off by a ratio, not a set amount. 67 instead of 60 means it's almost 12% off. So if it says 100, you would be going 112, if it says 50, you would be going 56, at 25, it would be 28, etc.

 

[smartcarkiller]

I just talked to my guy and he said my torque conv. was custom built out of Utah and its a 2500 stall. He also seems to think my original tach is not reading right so he is gonna drive it for me next time I'm in his area. He came in 3rd for engine masters 2006 with his engine build and I am very lucky to have him in my corner when I get stumped. He also said that there is probably nothing wrong with it, He said "Bryan you have a strong engine with some fairly loud pipes so its not a pussy cat nor is it gonna purr like one." Oh yea and the tranny fluid looks good considering it hasnt been changed in a while.

 

[andyblack]

It probably just sounds like it's running faster than it is then. I tend to overestimate RPM sometimes when I listen to an engine run that has loud exhaust. I think some aftermarket tachs do too.