Exhause or Engine Brake ...

[FATCAT]

If you had a choice (an option when buying the truck) between the two for your B/C-Series or ISB/C series engine ... which would you opt for?



I know that Jacobs says they don't make an engine brake for engins under 10L, but, if there were a potential market for them on the I6 engines ... would you consider them ... even if the cost was double or a little more than an exhause brake.



(if engine brake ... single or multi stage brake?)



What benifits does one have over the other?

 

[78repowerwagon]

Mark me up for two multi stage engine brakes. The sound is worth twice the price.

 

[Joe G.]

From what I understand even if an engine brake was made for our Cummins it would not fit under the Dodge hood. Too tall.

 

[FATCAT]

Joe G.

if an engine brake could be made to fit (even if the hood was raised a little in the center) ... what would be your choice.



Possibly in the future, if there were enough people hauling/towing ... enough of a market, maybe Jacobs would build one in the coming years.

 

[Joe G.]

Actually, I've never thought about it. My Pacbrake works fine. I'm upgrading the thing by plugging up the hole in the butterfly after I install the new valve springs I just got. I experimented with it once just after I got it by trying to tow my TT from US101 to Redding, CA without using the service brakes except for other vehicles and in town. I managed to do that. There are a couple of steep 20 MPH turns on that road. I guess what I'm saying is that I don't need a better brake than I have. Especially after I upgrade it. I don't think I would want the extra noise a Jake makes anyway.

 

[Champane Flight]

Jacobs?

I would take a multi stage Jacobs brake before a exhaust brake anyday. I cannot believe that they can't make one for the 5. 9 Cummins. The total height of a Jacobs brake on a 400 Cummins is 3". I just don't think they think there is a big enough market.

 

[illflem]

The vast majority of 5. 9s are used in constuction and marine, no need for an engine brake there.

 

[drees1]

Compression brakes are not as effective on non-unit injected engines like ours. They have maybe 2/3's the braking of a unit injected engine with compression brake.



A compression brake on a non unit injected engine must use exhaust rocker motion in adjacent cylinders, and even 2 cylinders away to actuate the timing to dump the exhaust valve on the particular cylinder being braked at that moment. This method of timing the dump is not as effective as using the rocker arm of the unit injector on the cylinder to be dumped, as timing is much better and the force is greater.



Also, to execute the brake on our engine, using the exhaust rockers of adjacent cylinders would require tieing the valve gear together for 2 or 3 adjacent cylinders. The individual valve covers could not be used.



However, since a unit injected engine can compression brake in excess of it's nameplate HP, there would still be a huge increase in braking over an exahust brake. The sound with an open exhaust would be to die for



Doug Rees

 

[R.E. Miller]

By the way...

If you really want a "Jake" just drop the ISL in your truck, you can get those with jakes. The ISL is a stroked version of the ISC, neat engine.



Russell

 

[Roger rodbolt]

An engine brake is a neat idea but I don't think the hood clearance is your problem. Engine clearance under the cowl will be the real challenge!! Have you changed push rods on #6 cylinder? Larry

 

[WDaniels]

No question if there were a choice, A Jake.

WD

 

[nickleinonen]

3 stage[2,4,6] compression brake would be fine for me thank you

 

[R.E. Miller]

Originally posted by Roger rodbolt

An engine brake is a neat idea but I don't think the hood clearance is your problem. Engine clearance under the cowl will be the real challenge!! Have you changed push rods on #6 cylinder? Larry

Good thinking there!!!! Unfortunately, the Volvo engineers didn't seem to catch that when they slammed the N-14 in their trucks. The rear head has to be lowered with the push rods in it because the intake push rod will not fit due to the fire wall, THIS will really Pi22 you off after you have torqued the bolts.



Russell

 

[C. Harlan]

I would definitely go with the engine brake!!! I used to have a Pete 379 Extended hood, 13 speed with 12 and 13 up on the dash, 3406 4¼ cat, 6" Straights with 45° bullhauler cut on the end..... When you hit the 3rd stage, it would literally stop traffic dead in its tracks!! And if that did not work, there was always the train horns!!!! I would definitely go with the engine brake!!!



-Chris-

 

[Champane Flight]

Older Cats

The older Cats had retarders, they worked great. We had them on the old 325s . They worked on the princible of hydralics, the engine would pump fluid into a converter, which would flow against the normal flywheel rotation. They were heavy though.