stealth engine break

[oilburner]

Does anyone know what the diffence in a stealth break and a regular jake is, the 98 454 we have has a steath and it says on the dash for best proformance use at 1800 to 2100, it hardly makes a sound when jakeing and does not seem to hold very good, the 94 we use has a better jake, so what is the deal with the stealth i can't find any info on it.

[Superdog]

probably can't find info because it was a joke and they quit using them,I had a '97 CH with one on a 427,it was pretty worthless.

[daveigou]

The stealth had an extra gate behind the turbo, it was a combination engine brake and exhaust brake to make up for the poor performance. It was only offered for a short while.

doc024.pdf

[rw613]

The stealth had an extra gate behind the turbo, it was a combination engine brake and exhaust brake to make up for the poor performance. It was only offered for a short while.

and you cant get parts for them anymore

[oilburner]

So what do i need to do to change it over? can i use the jake heads or do i need to change them to

[turckster]

So what do i need to do to change it over? can i use the jake heads or do i need to change them to

From The Mack EIS web page about Jacobs Extarder engine brakes:

"An E7 engine equipped with a Stealth™ Retarding System will have the following different, or additional, features:

• 
  Heavier inlet and exhaust valve springs
  
• 
  Heavier valve rotators
  
• 
  A different Jake slave piston setting
  
• 
  An Extarder unit
  
• 
  Air supply for Extarder control
  
• 
  Different electrical connections to provide for Extarder-only operation (with dash switch in LOW position), or Extarder plus Jake Brake on both heads (with dash switch in HIGH position)"
  

I would assume you could remove the stealth exhaust brake/gate and not have to change anything else, other than plug an air line and adapt the exhaust. You may want to change the jake adjustment from .100" to .080-.085", It might help a little.

[oilburner]

From The Mack EIS web page about Jacobs Extarder engine brakes:

"An E7 engine equipped with a Stealth™ Retarding System will have the following different, or additional, features:

• 
  Heavier inlet and exhaust valve springs
  
• 
  Heavier valve rotators
  
• 
  A different Jake slave piston setting
  
• 
  An Extarder unit
  
• 
  Air supply for Extarder control
  
• 
  Different electrical connections to provide for Extarder-only operation (with dash switch in LOW position), or Extarder plus Jake Brake on both heads (with dash switch in HIGH position)"
  

I would assume you could remove the stealth exhaust brake/gate and not have to change anything else, other than plug an air line and adapt the exhaust. You may want to change the jake adjustment from .100" to .080-.085", It might help a little.

Thanks everyone i will try it.

[41180]

we have a 98 CL713 with a stealth brake and it works great. .as a matter of fact it broke once and the regular jake brake with out the stelth hooked up is awful. so we put a pacbrake exhaust brake on it. we had a 95 western star with a 425 cat and the 454 with the jake and stealth combo outperformed the cat jake. i guess alot of people didnt like them but we have had good luck we bought the truck brand new and like the stealth. my dad actually built a 07 CL glider kit with a vmac 2 427 and installed a exhaust brke on that as well. works great . we are in the process of installing a pacbrke exhaust brke on our superliner with a E9 500 as well.

[oilburner]

we have a 98 CL713 with a stealth brake and it works great. .as a matter of fact it broke once and the regular jake brake with out the stelth hooked up is awful. so we put a pacbrake exhaust brake on it. we had a 95 western star with a 425 cat and the 454 with the jake and stealth combo outperformed the cat jake. i guess alot of people didnt like them but we have had good luck we bought the truck brand new and like the stealth. my dad actually built a 07 CL glider kit with a vmac 2 427 and installed a exhaust brke on that as well. works great . we are in the process of installing a pacbrke exhaust brke on our superliner with a E9 500 as well.

I was looking at it today and the exhaust brake is missing on the truck, i guess someone has already taken it off. But to be honest i have never seen a mack that had much of a jake break, the strongest one i have drove was a old 350 2v with a dynatard and it wasn't much.

[41180]

yeah that 98 should be alot better than a old e6 350 you might want to invest in a pacbrake . i know ours is awful without the stealth/pacbrke. i think they had the jake detuned on the trucks with the stealth setup. the E7s and etech jake brakes are not that bad alot better than a dynatard

[oilburner]

yeah that 98 should be alot better than a old e6 350 you might want to invest in a pacbrake . i know ours is awful without the stealth/pacbrke. i think they had the jake detuned on the trucks with the stealth setup. the E7s and etech jake brakes are not that bad alot better than a dynatard

right now it's not as good as a b model cat, and they did not have much of a jake, but i had it off road and in the lower gear it held ok but i feel like it could be better, i thougth only one head was working so i unhooked one, nope they were both working, and there is quit the delay before it kicks in and it wont jake under 1300 rpm, so i am thanking it is still the steath jake setup without the pacbrake, because the switch does not interfear withe the jake, low and high can not tell any deffernce.

[rsb502]

the stealth brake was a Jacobs compression brake and an exhaust brake the exhaust brake was the stealth part making the exhaust quieter. I have removed the exhaust brake from a friends truck and changed the wiring to match a standard Jacobs E7 engine brake hi-lo-off,or two heads, one head, off the added strength of the valve springs is actually a good thing for the engine and wont hurt a thing. I have also replaced the factory oil pump with a high volume oil pump from...... PAI I think and the added oil flow made the brake work great it had to almost double the braking effort. I know the settings on the Jake on the stealth trucks was a little wider check the gap and set it to that of a standard E7 Jake and it will work a little better.