I bought a 94 Ram 2500 with a 5.9l as I needed something bigger. Its mostly a parts getter/tow rig. We pulled a trailer with some tools this weekend and while it did alright I want more power (who doesnt?) So my plan was to pull the heads off and have hard seats put in and a valve job, basically a refresh, do a cam, cold air intake, headers and exhaust. At what point do I need to modify the computer and is modifying the computer on a 94 even possible? My desktop dyno says the changes Im going to make are gonna be worth between 50 and 60 hp and the same in torque. Two cams Im looking at, both are Comp. The bigger cam is 210/220 @ .050, .480/.512 lift, 112 LSA. The smaller is 199/206 @ .050, .480/.480 lift, 112 LSA. Help is appreciated!

I would run the smaller one, TQ and mpg will be up, if you want a tad more get some 1.7 rockers to help out in the lift department without increasing duration.

A new magnum engine trick I just thought of... I just did a plenum gasket on a truck and added another spare plenum plate I had spaced about 1/4 inch down from the stock one and it seems to be running about 20 degrees cooler IAT by keeping the hot oil off the bottom of the intake. Pinging is pretty much gone also but some of that could just be not sucking in oil.

Not really much support for that computer but you can advance the ign timing by slotting the crank sensor mounts and get 2-3 degrees advance. I would try running a set of 460 ferd injectors to get a little more flow and better atomization. The fuel pressure on the earlier truck like that is a little lower than the later ones or I would recomend the 5.4 injectors.

Thanks that helps, I was definitely leaning towards the smaller one. Like I said this is a tow rig, definitely not a hot rod. Just wasnt sure how big, if at all, i can go with the stock computer before running into problems. Hughes has a decent write up on modifying these years for tow and they also recommend a 180 stat; I plan on giving them a call to speak about it as well.

I don't think you're going to see any noticeable towing gains with that cam, and surely not 50-60hp. I'm not sure off hand what the stock 5.9 cam specs are, but they can't be that far off.

With the smaller cam you might see 30-40hp gains at the max. The heads are what kill the performance and were designed with strict bottom end torque. To get another 20-30hp you need to junk the stock heads and get some EQ heads. If you had a 96+ truck I would highly recommend fixing the plenum gasket, if it hasn't been done yet, 52mm TB and a set of headers along with a tune and you wouldn't even need to worry about the cam or heads. If the plenum hasn't been fixed already there will be some mpg increases with that and maybe a slight touch of power if you are pinging. Being that it is a OBD1 I wouldn't change the cam unless you go with an RV cam. The computer will learn a bigger cam but not to the full degree. Some bolt-ons will do you fine.

I talked it over with Hughes. They said on a motor like this it isnt worth the EQ heads, he admitted that was him just being frugal and assuming the stock heads arent cracked. Although according to the numbers on their site with just the replacement version of EQ, the stock magnums outflow them to .300 and they are barely better at .400. The stock magnum cam is like 180 or 178 @ .050 and its on a 116. With the smaller cam I wont need to touch the computer, and Hughes figures if I do a throttle body, headers, exhaust, cam, K&N intake, I'll be right around +45-55 hp and torque. I may pull the stock heads and have them freshened, just cause its 10 more bolts from where I'll be, why not throw some hard seats in them and be done with it.

Correction, stock cam is 182/194 @ .050, .411/.430 lift

The eq heads are tons better than stock even assuming the stock ones aren't cracked. There is massive gains to be had with the 2.02 EQs. Stock the magnum head flows around 190cfm intake and the EQs are around 240cfm intake unported IIRC. I'm not sure why they said it wasn't worth it, but if you are looking for extra power the bolt ons will be a nice upgrade.

I also wouldn't waste my money on a cold air intake. I've done countless tests at the track on Dakotas and Rams and nothing was measurably gained by going that route. Save your money..

One thing you should do right now is to change the carrier bearings in the Dana 60, DAMHIK! I lost one at 118K in my 96 2500 and I went online to see why, and found lots of instances of failure and many recommendations to change the bearing every 100K miles. My carrier was destroyed and the pinion took several teeth off the ring gear. Not easy finding a replacement carrier so far.

You can not feel a difference bolting on just a set of EQs, been there done that. You can feel the extra TQ down low with a good cam like the one mentioned. A bigger TB by it self you can not feel. All together would be real nice and help all through the RPM range.

In my experience with these magnum engines a good cam (short duration high lift and a little tighter LSA) is the best thing you can do for low RPM.

As for a cold air intake, how can it do much when the air is baked after it goes through the air tube on the plenum pan? Keeping the hot oil off the bottom of the intake reduces air temp and increases density as it flows through the ports/valves. I think the biggest reason the hughes air-gap intake makes such a difference is the air-gap not the runner shapes/lengths. When it was -20 degrees this winter my IAT was reading manifold air temps well over 100 degrees during steady cruise. How the heck can air that hot make any power? Adding a K&N CAI did almost nothing for IAT at those frigid temps. This is what lead me to try the extra plenum plate with a space between them.

PS if you pull the heads put on some of the thin mr-gasket head gaskets for a small compression bump.

EQ heads won't necessarily give you more bottom end torque but yes you can feel the difference if you already had a good intake on there. The stock beer barrel flows about 180cfm and the stock heads flow around 190cfm. If you take the supporting mods of an M1 2bbl and bolt on the EQ heads there is a TON of difference across the band especially over 2500rpms. Now if you are trying to make a stump puller then don't bother switching the beer barrel intake and Keep the stock heads. The headers and TB upgrade will NET you seat of the pants difference all day everyday.

The reason why I am debating even the small cam swap is that the computer will not learn it fully, will it improve? Yes it will some but you may lose a little low end grunt, may not be much but you probably will. I do agree that higher lift with a shorter duration and a tighter LSA will help a lot and will help down low.

EDIT* I misread the specs on the smaller cam, you will actually like the cam that will actually help across the whole rpm band. Sorry about the confusion.


Here is my suggestion is you want decent power gains and keep your low end up to par.

Replace the intake belly pan with the one from Hughes.
Get a 52mm TB
Get some longtubes or mid length headers. Pacesetter or Spintech
Get some nice Harland Sharp 1.7 RRs
Get a small Mopar stall converter 2200-2400.
If you are feeling lucky go ahead and do a band adjustment on the trans, get the Borg Warner GPS and get a trans go shift kit.


Just that alone will wake up the truck a ton.

The hughes intake pan is aluminum and conducts heat through it to the air even faster than the factory steel pan, of course being aluminum it will expand and contract closer to what the intake does so it should blow the gasket less.

They should have made it of phenolic resin.