Homemade Exhaust Brake

[totalloser]

Every time the air charge is compressed, it soaks up power. A principal called adiabatic heating creates a significant heat charge that is dissipated to the engine and released through the radiator. Brakes turn mechanical energy to heat energy and dissipate through contact with air at the rotor/drum. The heat from this process is energy bled off from forward movement/fuel being burned (at idle only hopefully!!).

Cutting off the exhaust flow from holding the exhaust valves closed or closing off the exhaust flow makes the engine compress twice (compression stroke as well as exhaust stroke). This dissipates significantly more power, thus better braking.

Any actuator will need to be run by something more reliable than a solenoid. Solenoids adequate for this application would draw more juice than would be practical, and only pull one way. A double acting cylinder would be in order. Large for vacuum or smaller for pressure. Hydraulic would work but then you need all sorts of complicated tanks, and lines. Plus weaker air systems and vac systems are more than adequate. 2000psi hydraulics would be a waste of time.

Control of a system like this is well suited to air solenoids controlled by switches. Very little power draw, and easily controlled by multiple switches. (IE shifter switch and off idle kill switch). Matching the leverage to the butterfly is the tricky part. Get out your calculator. And the shaft should probably be stainless steel, and be bushed with bronze to prevent bindup.

A warmup valve from a Ford Powerstroke would work, as well as possibly those springloaded exhaust cutoff valves used in late 70's cars to garner fuel efficiency. Simply remove the spring and add a lever.

And you definitely can scatter your engine with this. The exhaust can build up enough to hold the valves open and cause piston/valve contact. Exhaust tubing should withstand at least 1000psi, and I think 60 can cause interference with the engine components.

I made my own steering and ram assist, but I decided my skill level was iffy when considering fabricating an exhaust brake. Take your time and understand the consequenses, says I!

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01 24v 100hp tips, 4"ss BDbrake &steering brace PSCpump 1.5"dom steering tapped box 1.5"ram manual CAD switch dual carters 3.55's LSD, big shaft nv5600/241HD 6 35's inners pulled in (no spacer) Ugly black and thrashed!

[renopker]

[IMG][/IMG]The 12v have light springs so you need to change to the 60# springs,I tried to see what size the hole was from pics.I took but cant tell looks like two small maybe 3/8 holes here's a pic from under the truck this is with my twins so there's very little room and had to mount the actuator differently

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98 12v,2wd twins,3:55,g56 6speed,elec fan clutch,100 hp sticks, 10 plate FF aFC fB,3gsk Valair ats,fluid damper,60#springs,o6 exhaust brake,High Idle,prime loc, 4"exh,piller mount

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Last edited by renopker : 01-10-2009 at 12:06 PM.

[BigT18]

I dont know if people are saying whats already been said, but i want to make sure on this. Drilling a 3/8" hole in the butterfly alleviates the need for 60# exhaust springs. Correct? And to prevent too much pressure build up, a throttle switch needs to be put into the system. But running it with no fuel and a hole in the butterfly will not cause engine damage. Correct? Just tryin to err on the side of caution.

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1995 Cummins 12v Reg. Cab 4x4 5 speed, 250,000 miles, boost/pyro, straight piped 5" stack, #10 plate, pump cranked, coal rollin.

[renopker]

Originally Posted by BigT18

I dont know if people are saying whats already been said, but i want to make sure on this. Drilling a 3/8" hole in the butterfly alleviates the need for 60# exhaust springs. Correct? And to prevent too much pressure build up, a throttle switch needs to be put into the system. But running it with no fuel and a hole in the butterfly will not cause engine damage. Correct? Just tryin to err on the side of caution.

No you need 60# springs hope this helps the bigger springs are required to close the valves because of the extra pressure on the stem side

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98 12v,2wd twins,3:55,g56 6speed,elec fan clutch,100 hp sticks, 10 plate FF aFC fB,3gsk Valair ats,fluid damper,60#springs,o6 exhaust brake,High Idle,prime loc, 4"exh,piller mount

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Last edited by renopker : 01-10-2009 at 12:10 PM.

[illflem]

I dont know if people are saying whats already been said, but i want to make sure on this. Drilling a 3/8" hole in the butterfly alleviates the need for 60# exhaust springs. Correct?

Pac-Brake uses a 3/8" hole in the butterfly for folks who don't have 60 lb springs. Their brake kit includes a nut and bolt to block the hole for folks who have 60 lb springs. All I can tell you is that this system works.
One guy I know who made his own e-brake also installed a 100 lb boost gauge upstream of the butterfly to make sure it didn't exceed 60 lbs back pressure.
It didn't.

I'm waitin on my Bimba pneumatic air cylinder and a solenoid valve. Should be here either tomorrow or monday.

If this doesn't work why not use a choke cable to operate the butterfly?
Seems I recall the old Powerstrokes had such a set up for faster warm ups.

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Bill
'95 2500 4wd auto
'95 3500 5 speed heavy hauler
Not stock

[BigT18]

Originally Posted by illflem

If this doesn't work why not use a choke cable to operate the butterfly?
Seems I recall the old Powerstrokes had such a set up for faster warm ups.

Thats a good idea, i didnt think of that.

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1995 Cummins 12v Reg. Cab 4x4 5 speed, 250,000 miles, boost/pyro, straight piped 5" stack, #10 plate, pump cranked, coal rollin.

[R_Zachs]

i have been thinking about this and ive read every post and thers alot of good ideas. but the badlanz exhaust cutout is a good idea too. thats the one i was thinking of using and drilling a 3/8" hole in it. and have a push button switch and a delay relay that keeps it on like the dome lights but get one for like 1min or so. so it stays on after you hit the switch so you dont have to hold the switch

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05 3500 QC LB 6spd Smarty JR(POD) -ISSPRO fuel/EGT/Boost|$50 4" intake|MIA silencer ring,cat,muff|2" Procomp LVL kit| 100w KC's, HB4 80w Fog bulbs|sprayed bed|diamond 5th wheel|PDI Manifold 4" DP 5"straight to 5"stacks

[aautio1004]

Just to clarify also, we did determine that the 24valves have the 60# springs in them, correct?

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'01 2500 4x4 QC/SB, 4" straight pipe, Amsoil intake, Autometer gauges,Smarty,Edge Comp Hot,Holley Blue,HX40,Recon roof led's, manual high idle, built up auto trans, 89% stall TC
'07 Chev 2500 CC/LB Duramax LBZ Edge Juice with Attitude

[countrycummins99]

yes they do

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99 DODGE 24VALVE, FASS 150, EDGE COMP/SMARTY REVO STACK/100HP COALTRAIN STICKS ,BHAF,TC LOCK UP SWITCH 5"MITER CUTS, 3.55 ANTI SPIN ,SMOKE SWITCH, SILENCER RING KILLED, GAUGES (FUEL PRESSURE, TRANS TEMP, BOOST, EGT))INFAMOUS 53 BLOCK 293,780 no crack

[illflem]

Originally Posted by aautio1004

Just to clarify also, we did determine that the 24valves have the 60# springs in them, correct?

According to this they do Dodge Ram Diesel Engine Evolution

Still not certain about the '98 12 valves though

__________________
Bill
'95 2500 4wd auto
'95 3500 5 speed heavy hauler
Not stock

[Challenger]

i bought a couple of used exhaust brakes off ebay $50-$75.They are pretty common on the med duty isuzu npr etc

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96 Dodge CTD 3500 4x4 black extracab dually auto 3.54 no mods

[lvin4jc]

Originally Posted by Challenger

i bought a couple of used exhaust brakes off ebay $50-$75.They are pretty common on the med duty isuzu npr etc

What size are they???

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2001 4X4 Auto SLT Laramie - DANA 60/DANA 70, 3.55's - Isspro Gauges, FP, Pyro, Boost, Trans. Temp. - HBS 2" Leveling Kit - Straight Pipe - Amsoil Nanofiber 4510 CAI - Quadzilla XZT+ - Debadged - 285/75/16 Firestone Destination M/T's

230,000 miles as of 08/09 - - All Cummins all the time!