General performance questions

[patriot9879]

Hi, I have a 98 k1500 with about 127k on it. The engine checks out fine, and seems to make pretty good power even at 5000 feet. The problem I have is with my transmission. I've only owned the truck for a little over a year, and I get the impression that the previous owner didn't take the best care of it.

Anyway, I need to get the trans re-built, so I wanted to know if there are any performance/efficiency upgrades that I should make while it is apart. Also, I would like to use a different torque converter for more off-the-line power/torque. What is a good rpm range to use with the stock motor?

Lastly, I have been impressed with the results that others have posted regarding the custom tunes. Do ya'll think that it is worth it to get a "custom" tune for basically a stock truck? And, with my re-built trans, are there specific adjustments that I can have made to the trans settings that will impact the performance?

Thanks...

[NEUMANNZZ]

I would recommend kevlar clutches, aftermarket sun shield, corvette servos, aluminum accumulators to replace the plastic ones. transgo stage 2 (hd2)shift kit. as far as torque converter goes, get a lockup with 2000-2500 rpm stall, if you tow a lot get a lower one. for racing get a 2800 to 3000 rpm stall. and a deep trans pan or a transcooler if you dont have one.

[Diamond Jim]

Visit the Raptor (http://www.transmissioncenter.net/highperflist.htm) web site for transmission info and parts.

A Wester's (http://westers_garage.eidnet.org/) tune for regular gas, upping the rpms limit to 5400, removing a little of the torque management, will make a noticable increase in performance. This was the first one I had done to my Burb. It also gave about 1½ mpg increase on the highway. I have had the tune re-done four times since then as I have done some mods. It really works good on the 5.7 vortec engine.

I don't know about any of the other tunes. I did drive a '98 ECSB 5.7 pickup that had a Nelson tune and it was pretty hot. But that tune was done at the Nelson place on a dyno and done for hi-test gas with all torque management removed. I don't think the little extra performance he got is worth the difference in price of hi-test gas.

[Frankenbiker]

Anyway, I need to get the trans re-built, so I wanted to know if there are any performance/efficiency upgrades that I should make while it is apart. Also, I would like to use a different torque converter for more off-the-line power/torque. What is a good rpm range to use with the stock motor?



Going with a slightly higher stall speed will do wonders. Most recommend going with a 'vette or S-10 converter, which run about 2000 RPM stall. I tried this and liked it, but discovered later that the slipping I was experiencing was in the tranny, not the converter. I went back to a stock converter till I had the tranny rebuilt. Once the rebuild was done, we put a 2000 RPM converter back in it, and would up overshooting just a little. We put in an 1800 RPM converter and felt that was the best compromise.

You needn't go any higher than 2000 RPM (IMHO) because that will be too much for a stock engine.

Additionally, the 4L60E's of 1998 vintage have most, if not all, the durability upgrades applied to the family over the years, so unless you plan on getting a gut-buster motor later, or plan on doing a lot of pulling, you needn't spend the considerable extra cash on "heavy duty" parts. All the biggest, baddest, most expensive parts are a considerable amount of money (like $1500-$2000) that you can spend elsewhere, as long as you're sticking with the stock motor.

-blaine