Hughes Performance Converter

[Power Wagon]

I FINALLY have my Hughes converter installed.



My only lament right now (after my FIRST drive) is... Why the heck did I wait so long?



On a good grade, the truck accelerates MUCH faster than before. Anything above 10 MPH acceleration is definitely the same.



From a standstill, the truck will wind to the shift point, which is almost governor cutoff (2700 for me) and when it shifts, the engine rpms drop a LOT.



I'm quite sure that my 1/4 mile MPH is up, though the instant boost and tire spin when you hit the throttle is gone.



The truck jumps off the line and about 3 truck lengths later, the turbo screeches and it MOVES like it means it.



I'm leaving in a few days and will be doing about 4K miles of towing. I'll be back late August, though I should be able to give a towing update while on my trip (not a vacation).



Anyway, initial impression... . I'm impressed.

 

[moparguy]

Mark, care to share price. I suspect you've raised the pressure to help the clutches deal with the new converter.



Good to see you posting.



Ronnie

 

[Bob Beauchaine]

Hi Mark

It's good to see you back on line again - it's been a while. It's also good to see you are still "BOMB"ing your truck.



Bob

 

[CDegner]

The price for the Hughes TC runs about $385 +/- a little direct from Hughes. Been thinking about one of these myself. Just might have to do it.



Carl

 

[dan brooks]

I love my Hughes converter. Any improvement over stock is a good thing, but I was really surprised at just how much difference it made.

 

[Power Wagon]

Originally posted by CDegner

The price for the Hughes TC runs about $385 +/- a little direct from Hughes. Been thinking about one of these myself. Just might have to do it.



Carl

I paid just over $200 at the local CHEVROLET dealer for it.



They special ordered for me, and gave me the "special order" price which is to say, probably a few percent over cost. IT was a lot less than buying direct.



Hughes has many dealers who buy at wholesale prices. If all else fails, I'm sure I can find ya a deal from them.



EDIT...



I do NOT suggest you use this converter without a 12 or 14 CM exhaust housing on your turbo. If you do, you're going to have a heck of a time getting up into boost.

 

[Greenleaf]

Why.

I'm interested in a new converter and flex plate but from what I have read, this new aftermarket converter is a tighter unit. Therefor it will work the engine more so than the OEM unit and will therefore build boost sooner... . right? ... ... No?





Or are you thinking RPM's?????



-S

 

[cerberusiam]

The answer is no Scott. A tighter converter will not let rpm's build as fast before transfering power. If you have a large housing and need 1800 rpm's to build good boost and the converter stalls at 1500 it will take a lot longer to get into the boost range to start making power. As Mark reccomended, a smaller housing will build boost faster so you don't have a dead spot between launch and boost coming up.



The problem with a stock converter is not so much the 'looseness' but the lousy TQ multiplication that happens when the power comes on. What is needed is a a dual stator converter that will allow a stall speed for the application and then get tighter the faster it turns to transfer the power. That would be why a good converter matched to your application is going to cost in excess of a $1000. Some body gotta pay for the R&D.

 

[cwienenga]

huges converter

very interesting on the turbo housing aspect. what does dtt do on his,I've never seen him mention changing housings to my knowledge. I've stayed with the stock 18? because I tow and have noted most threads say this is best for long pulls. with the pw injectors I get up to 21psi and don't have to worry about exh. temps. sure would like to cut down the converter slip though and have been waiting for mark to get this in so we could see the diff. Am waiting for his return and followup.



cliff

 

[CDegner]

Hey Cliff,

You gonna head up to PDR on Saturday for the 2nd annual (hopefully) 1st gen day?



Carl

 

[Greenleaf]

Confused...........

What you guys are describing is opposite of what I'd believe will occur or my head is full of cobwebs



I know the OEM converter will stall faster than the engine will build max torque. I don't really understand that theory but know it's stalling at 2000 rpm's. Where as a performance unit will stall about 1500 rpm's. Again I don't understand what difference this makes in engine performance only to say you will work the engine harder with an upgraded converter by using more of the torque at the wheels as opposed to the converter absorbing most of it and sending only a small % to the wheels.



When we put more of this available torque to work the engine will be under more of a load and it's load that the pumps senses when to send fuel to the pistons, thus generating boost.



Example: I can floor-board my engine w/transmission in "N" . 3400 rpm's and near zero boost. Do that with transmission in "D"; the rear wheels will have friction causing a load and boost will sky-rocket.



It's not rpm's that make boost... . it's the gov. sensing need for fuel to overcome load that injects fuel, that causes boost. Right!(???)



It sounds like a performance converter isn't much of a performance upgrade... just the opposite. I don't want to have to buy a different housing and now have more restriction to air flow.

Enlighten me o wise ones



-S

 

[moparguy]

Um, think of it this way, a lower stall converter is kinda like being in a higher gear on take off. If it were a standard transmission and you tried to take off in 3rd, it'd take longer for the turbo to spool up and start to build the boost requied to burn the fuel available.



The standard would be doggy off the line taking off in 3rd. . Same thing with a tighter converter. The smaller turbo will start to build boost sooner, making power available sooner, which is a good thing.



My little Bro has 91. 5 and I've been after him to change his converter, my concern is with the tighter Hughes, will he have problems untracking a load (15k) with his 3. 55 gears.



I can just see him trying to start off, up hill, with a load and the converter loading, the engine not getting upto rpms required to make some power and not being able to get rolling.

 

[cerberusiam]

Scott, remember the aneroid and fuel pin and spring and star wheel? Given you change nothing else but the converter you will not get enough fuel to build boost needed to push the spring down to let the pump deliver more fuel until the rpm's get high enough. If the pump can't deliver enough fuel the rpm's will never come up enough to let it deliver the fuel.



Its possible to have the truck set up to the point where under a certain load you can floor the throttle and all it will do is sit there and smoke and go no where. Mean while EGT's skyrocket not to mention what is happening to trans temps.



Actually the OEM converter stalls higher than the peak TQ so you loose a lot of the actual power generated. Peak TQ band runs from about 1600 to 1900 on the gen 1 engines so having a converter that will stall at the bottom end of that range and provides good TQ multiplication is a performance upgrade. Your using the engine in its power band and getting the power to the ground. The problem is the larger housings do not spin the turbo fast enough at those rpm's to build the boost needed to let the fuel delivered. One of 2 things needs to happen to make things work. Either we go to a smaller housing to minimize the turbo lag or we overide the fuel delivery system and tell it to fuel more at no and low boost to provide the exhaust to spin the turbo up faster. The first option gives you a clean relatively smoke free launch while the second will put you into competition with a destroyer and generate enough smoke to blot out the sun. A little gray haze is a good thing. The 'cloud of death' is not.



PB posted a stall test a while back to determine if the converter was too tight for the application. Run the truck up to a square cut curb and mash the throttle. If it will jump the curb your good. If it just sits there and smokes there is tuning to do.



With the auto trans you have to finess things a bit more than the manuals. You don't have the option of slipping the clutch until things get cookin'.



Talk to some of the converter builders and if they know their stuff they will start by asking what you think you input HP and TQ is going to be and what you will using the truck for. They have a pretty good idea what is needed if you can tell them how the engine is set up.

 

[cwienenga]

carl



can't make it up to the pdr this time. would like to represent the 1st geners but have a pt time job on saturdays so have to pick and choose when to take off. we were up at hoss's

recently and had a good time. look forward to meeting you sometime



cliff & judi

 

[hdm48]

Why not just run a lower first gear. They are available from mopar performance. Then you would have the best of both worlds

 

[Power Wagon]

The reason the tighter converter works, is that your engine makes maximum torque at around 1700 to 1800. That's the "twist" that moves your truck down the road. The stock converter will let you rev the engine past the maximum torque point and it changes the horsepower (rpms + torque) into torque.



Converters do this in varying degrees by style and design.



It's possible to build a converter that multiplies engine torque by 1. 5, 1. 7, or even 2 or more times. Generally, the more the difference in speed between the input and output, the more the torque is multiplied.



Rumor has it that the stock converter was designed for relatively high stall so that the engine could reach enough RPM to build boost. Also, it was designed with considerably inefficiency so that maximum torque applied to the transmission was reduced a bit.



Even though the engine won't rev high, I cannot get the truck to hold in place with the brakes. I can easily overpower the brakes with engine torque now. I could hold it back before.



It appears that this converter is more efficient, and multiplies torque enough to be more than it had even with the higher stall of the original.



BTW, towed with it briefly. It certainly lugs the engine down when pulling a grade, which helps keep the pyrometer down a bit.



***Edit****



My towing was more of a test than I thought. The trailer behind me that I thought was about 5000 lbs, turned out to be about 8500.



I weighed the gross truck and trailer weight and it turned out to be 15,400. I was able to pull a 5. 5% grade at 50 MPH. That's better than I could do previously with a little less weight. Pulled in direct, with the post-turbo pyro hovering at 900.

 

[Greenleaf]

OK, now I'm really confused :{



When you load the engine more the gov. senses this and delivers more fuel... ... ...

BTW, towed with it briefly. It certainly lugs the engine down when pulling a grade which helps keep the pyrometer down

I prove this to myself every day when I climb the long hill to my school. If I pull the hill in OD the pyrometer will run about 900° Then pull the same hill in 3rd, the pyrometer will be about 650° give or take. When I'm in OD there is more load on the engine and she gets more fuel.



In fact when you tow and overheat the engine you need to go down a gear.



I have been experimenting with my driving habit to work cause if I pull that hill in OD it takes a long while to cool down to 300° when I pull into the shop. When driving it in 3rd it's only a matter of moments to reach the shut down point.







I think this is a popular topic because we want to upgrade for increase performance but don't want to spend our $$$ foolishly.



Scott

 

[Power Wagon]

Originally posted by Greenleaf

OK, now I'm really confused :{



When you load the engine more the gov. senses this and delivers more fuel... ... ...







I prove this to myself every day when I climb the long hill to my school. If I pull the hill in OD the pyrometer will run about 900° Then pull the same hill in 3rd, the pyrometer will be about 650° give or take. When I'm in OD there is more load on the engine and she gets more fuel.



In fact when you tow and overheat the engine you need to go down a gear.



I have been experimenting with my driving habit to work cause if I pull that hill in OD it takes a long while to cool down to 300° when I pull into the shop. When driving it in 3rd it's only a matter of moments to reach the shut down point.







I think this is a popular topic because we want to upgrade for increase performance but don't want to spend our $$$ foolishly.



Scott

Let me address this in terms that make sense...



Your pump does not put out the same amount of fuel each injection over a range of rpm.



In reality, the fuel injected begins to decrease slightly around 2000 rpm and drops perhaps 5-10% at 2500. When the governor kicks in, you drop a LOT, right down to no fuel if you overrun the governed speed.



If you have a larger turbo housing, you probably don't reach full boost until nearly that speed where you start on the "downhill" slope. Thus, if you cram full fuel in at low RPM, you don't have the airflow to keep the pyro down.



On the other hand, I have the small turbo housing ,and I get maximum amount of air in each cylinderfull at 1700-2000, where you make maximum torque.



If I run up against the governor, the airflow thruogh the engine is so much less, that my pyro runs away if I pull s teady at 2500 - it will continue to climb past 950 real fast on it's way to where, I don't know...



I was never able ot sustain a WOT pull before changing converters... I always had to let up enough to hear the engine change and feel the power loss.

 

[cerberusiam]

Sott, take a look at your rpm's, speed, and throttle position when you pull that hill. Assuming you hold the same speed your rpm's are higher in drive then OD so you are flowing more air for the fuel you are using and since you have better leverage in drive your throttle position is less. Less fuel equals less heat. In OD to maintain the same speed your throttle position will be more and rpm's lower to maintain speed with less leverage. You now have more fuel less rpm's and less air fow so your pyro is going to go higher.



I can run in 100+ degree heat into a 30 mph head wind in drive up against the governor at 70 mph grossing 10k and the engine will not heat. If I try to do the same thing in OD the rpm's drop and the engine will peg the heat gauge. I have a stock converter that is shot as far as the fluid coupling is concerned. At anything over 20 mph I can floor it and it will drive right thru the coupling and up against the governor and wait until the thrans catches up. If I had a converter with a better fluid coupling the truck would either move or blow the tires away. In addition I would use less throttle (less fuel) to maintain the same speed and probably not have as high EGT's as I now have. I suspect the reason Mark has high EGT's at WOT throttle is the turbo setup he has. The 12 cm housing works real well for quick spooling and driveability but it suffers high drive pressures and matched with an H1C it can get hot at WOT.



I have the 16cm with a modded HX35 but it does almost no good because I can't get the power to the ground with the lousy fluid coupling. With a better coupling and the same stall it would be perfect.



Just saving my nickels and dimes for the custom lock-up TC and 47RH... ... .....