Just how many RPM's can a 2V 4.6 turn safely. I had my rev limiter turned to 6500 RPM's and bounced it off that a few times. 4.10 gets you thru 1st pretty quick. So I dropped it back to 6200 with the shift point at 6000. I've seen some aftermarket white face gauges for the GT's that show the redline at 6800 rather than the stock 5800. It pulls really hard up to 6500 with no sign of valve float. What can these motors really turn? Thanks

 

Figured 6500 was a little high. Guess I'll leave the shift point at 6000.

 

You need to log your vehicle acceleration rate to determine where you should be shifting.

 

Unless your motor is built there is no need to go beyond the factory redline in my opinion.....put your car on a dyno and watch right around the factor redline your power fall off like a fat b**** jumping off a cliff

 

I personally don't even want to hit 6K let alone 6800. My max HP is at 4800 rpms but i have my msd shift light set to 5K. a very very small hp lost at 5K.

 

the stock intake and cams stop making more power at 5200rpm and then lean over and start reducing power. You should not exceed 6000 rpm in any case as you will eventually find a weak spot in the motor and probably ventilate part of it. RPM is the rod killer. Killed rods kill blocks.

Who cares what a guage overlay says, if you don't build the motor don't turn the RPM. You go slower by exceeding 5200 rpm before a shift.

 

Thats not always true. You need to rev high enough so when you shift, the rpm's drop down into the power range. Thats why you need to data log your acceleration rate to find your best shift point. Looking at a dyno graph isnt the right way to determine your best shift point. Either way, you shouldnt be reving over 6k on a stock block or valve springs.

 

stock motor leans over at 5200... that's always true. If you shift from 5200rpm in any gear and you do it quick you'll never drop below 3000rpm which is where the powerband of stock-ish 4.6's really starts. datalogging is best but not really required when you know the areas of maximum power generation in the RPM window.

 

I didnt say that the motor leaning over 5200 isnt true. There are calculators out there that will tell you your best shift points and even those can be off. So just knowing the "areas" of maximum power simply isnt enough if you want to get the most out of your car. This is easy enough to datalog when you have an XCal, so I dont see why you wouldnt do it if you own one. Now Im not saying you need to go out and buy one if you dont have one. The list goes on and on if you want to talk about things that arent necessary or required. But thats also what separates everyone.

 

Auto's won't shift but so fast even with the shift pressure turned up. If I shift at 5200- 5500 RPM's it falls flat for a second then starts to accelerate hard again, even with the 4.10. When I shift at 5800-6000 it pulls strong from the shift on. Maybe I've just got flat motor.

 

Perfect example. BTW, my auto shifts so fast/ hard, when Im on half throttle ill chirp the 1-2 shift. Autos will shift faster then a manual if you know how to do it.

 

Oh it shifts plenty hard. I dialed back on the pressure a little on the 1st to 2nd shift because it would spin about a half a car length in 2nd. If you leave it in drive and let it shift on its own it's fine. But if you manually shift it, it won't shift as soon as you click it into 2nd. The factory shifter sucks and you can't find a rachet shifter for console mount for the 2000-2004 models. They all stop at either thhe 99 or 2000. I'm not sure on the year.

 

Too much line pressure is bad for the transmission. There are ways to make the car shift harder/ faster that wont harm the transmission. In fact, they actually benefit the transmission. Even when you manually shift, the computer is still going to shift it as you found out.

 

It's funny this started as a redline question and is moving toward trannys. But thats OK. I Think a better torque converter wouldn't hurt either. The stalls normally knock out some kick to the shifts and keep the RPM's up into the next gear. I just don't know if the stock tranny will hold up very long with an increase in stall speed.

 

If you can get traction a converter will take off around .5. Im running a 3500 stall on my DD. Youll need a tranny cooler. Other then that its fine. The thing you dont want to do on a stock tranny is put on a trans brake.

 

Damn, 3500 seems like it be tough to drive on a daily basis. I was thinking around 2500 - 2800 tops. What brand of converter are you using and does it still have the lockup on it?

 

No, it really doesnt make a difference. The car will still creep at idle. It might take a bit more gas to get moving, but if you dont know exactly how a stock car feels then you wont notice it. Going with a 2500- 2800 stall is pretty much pointless considering its not much more then stock. You should be locking up the converter in 2nd and 3rd gear. Unless you're pushing some serious power. If its not being locked up, then its costing you time. IMO, I wouldnt go with anything less then 3200. That being said, a lot goes into picking the correct stall.

Im using a PI multi disk converter. HOWEVER, if I know today what I knew then, then I wouldnt be using this converter. I would have purchased one from www.bc-automotive.com They make billet single disk converters that have as much surface area as a PI multi disk! A PI single disk converter only has 17 sq. ft. of surface area where a stock one has about 13! Talk about clutch slip! On top of that, PI also uses ****ty clutch material and a lot of guess work goes into their converters.

 

Thanks for your info. I'll be checking into their site to see what they've got. Untill then I'll just have to live with what I've got.