farmer52

1990 would be near the end of the E6s. Perhaps Mack decided to incorporate the 5" turbo on the later engines. I left Mack in 1986 for greener pastures (so I thought).

Heck Tom...the forecast for PA is high of 40 with ssssssnow showers. 52 sounds balmy! Am going to try and get the MH in "winter storage" this weekend.

This is turning into Leversole's "pimp my ride"!

Turbocharged engines are developed as a system (inlet, fuel, combustion, and turbo) using various components and settings. As I previously stated, increasing the exhaust diameter will yield little if any increase in horsepower. The best way to determine any change is to put it on a chassis dyno, measure the power with stock exhaust system then remeasure with new system. My bet is the change will be minimal. As for the 4" exhaust...when I started working at Mack in 1985 (after spending years at the CAT house in engine development), I asked the question "why does Mack use a 4" exhaust system." The answer was "because EPA states a minimum of 4" to be used for the horsepower setting." My response was, "EPA sets a minimum, not maximum." During the development/evolution of the E6 I doubt anyone thought about putting a larger outlet turbo on the engine. The E7 was just being designed and if I remember correctly, it was initially going to use a 4" outlet turbo. I suggested changing to a 5" on the E7 for all ratings. The rest is history. To retrofit an E6 with a 5" outlet turbo would require "resizing" the turbo to get the best efficiency. That's my story. BTW, it is interesting to note the engine label....1990 standards, built 05/1996 and set to 1979 EPA standards. Very interesting!

A larger exhaust is not going to hurt but doubt if you will see any appreciable gain in horsepower. You are restricted at the turbo and the 4" pipe under the cab. The only gain will be the "curb horsepower" = visual appeal. Post some pics.

Does one need to connect the air dryer heater if it is not being used in freezing temperatures? I been thinking about installing a Bendix AD-IP dryer (spin on cartridge).

Nice MH...cue "the" video....

I'm beginning to regret posing for the BMT "family" pictures. The FBI, FAA, and TSA likely have our mugs on their bulletin boards. It was probably gearhead trying to land on the PA green stamp that alerted the authorities to our activities. BTW, glopped is past tense for "glop".

Nice video...thanks for posting. And a 2-stroker too.

Tom, Nice pics of the country side. Thanks for taking and posting them. Hmmm, chicken....yum yum. I think you should have a BMT cookout. BTW, did the Head Driving Instructor have dirty knees? Just wonderin'.

Thanks Glenn. I will give it a try.

Mack Museum email.... mack.museum@macktrucks.com

Have you contacted the Mack Museum with your VINs and questions? Might be a good place to get answers.

Will a faulty unloader valve cause the wet tank to lose air (I have no air dryer on my MH)?

1988 would be E6 not E7. Was one repowered?

Welcome to BMT and good luck in your search. There are some trucks listed in the For Sale forum.

According to the Bendix Quick Reference Catalog, the unloader kit for a Tu-flo 501 compressor is Bendix #279615N. I believe the Bendix "prefix" is 745. So that would make the Mack part number 745 279615N. Leslie - what is the model of air compressor on your Superdog?

Hey Rowdy. I finally figured out the video. You shot the video driving forward then reversed it so we think you were backing. Very ingenious. Seriously, nice job backing. I can back a short trailer but only in a semi-straight line or around a single "random" corner.

Correct. The CAT combine is a joint venture with Lexion. Actually Lexion is CLAAS. http://en.wikipedia.org/wiki/Lexion

Dang Jay...hate to see you sell this truck. But you have to do what you have to do. Just do your best to see it goes to a good home! Good luck! P.S. This truck needs to be in the Mack Museum.

Here is your opportunity to own a 1952 Worthington tractor. No connection. http://www.tractorshed.com/cgi-bin/photoads/classifieds.cgi?search_and_display_db_button=on&db_id=569624&query=retrieval

Tom, You needed a couple Winfall wimmin to help you move that grill. Just sayin'

Preciate? WTF...now he is throwing fancy words. I guess that is what happens when you are famous.

IFRC, the engine "slanted" to the right. That would counterbalance the U cab.

Yesterday's Tractors site has a serial number list with years (left column under Research). It does not mention the location of the SN.