Engine/Transmission (1998.5 - 2002) Silly Mods???

[RussW1911]

I have been reading a lot of threads about Exhaust upgrades and air filters and I have more questions than I started with. It would seem to me that HP/Torque starts with more air and less backpressure. I take that to mean that a quality BHAF and a good exhaust system (not just hacking off your stock muffler) would be a good way to go. Though cutting off the muffler may accomplish the same thing I want a slightly less obtrusive sound on my truck when towing. Quite to the contrary of what I had thought before I read that it was "Silly"and "a waste of money" to put on a BHAF and an exhaust system before going onto bigger better things like the Edge EZ or Comp. Wouldn't the Edge product be a better tool if the truck is able to use the power by being able to breath a bit better than stock. Seems like a waste to throw the computer on a stock truck if it can't utilize it to its full potential. Not taking anything away from the people who want the computer and nothing more. But, isn't it a little harsh to say it is silly to do a worth while upgrade before putting your money towards the big horsepower items. Some people don't mind hack jobs and half a$$ workmanship. Remember there are some of us that can appreciate a fine machine.

Again I am not trying to bad mouth anyone I am just wondering about this stuff before I start tossing my money down the bottomless pit... no no not my wife, my truck.

Russ W

 

[Whitmore]

Russ

you will prolly get alot of different oppinions on this one but I think that two of the most important things needing attention on our trucks is



getting cool air in for combustion

getting the hot gasses out of the exhaust



I have done extensive testing on the air intake oem setup and can tell you that it is very constrictive and needs attention.

see what I have done here





https://www.turbodieselregister.com/forums/showthread.php?s=&postid=522664#post522664



also I think the exhaust speaks for itself, a diesel doesnot need back psi like a gasser so why not make it easy to breath ???



Once it air in and exhaust out are bombed than a box makes sence to me , make sure you have gages to monitor the vitals of the Cummins FIRST and go for it.



cheers, Kevin

 

[LSMITH]

I will put in my . 02c.



The stock intake is just fine up to 325RWHP or so on a 24V. You have a turbo, that not only forces air into the intake but also sucks air through the filter and airbox. The stock turbo is capable of flowing all the air to make 325HP or so without excessive EGT. The stock 3" exhuast with no muffler or a free flow muffler is just fine up to 350RWHP or so.



You want to start upgrading, so you put on a BHAF at $30, (prices are all guess just for conversation BTW) a 4" exhuast at $400, and a PDR HX-35/14 at $500. Woo Hooo!!! EGT dropped from 1300 to 1150!!!!! You gained 10 HP (just a guess) from the turbo and exhuast with your cool airfilter!!! Where was the problem to begin with? It spools faster now huh? How much faster? There has not been anything to quantify the gains in spoolup, and to me . 5 seconds of turbo lag is not a big deal.



Over $900 for 10 HP? Not me, no way no how. For that same $900 you can buy a used EZ or VA, and some DD2's. You just gained 130HP, and STILL don't have EGT trouble!!!!! Now you can take the other $900 you would have spent on the upgrades after you "prepared" the truck for bombing and buy your clutch or a large part of a VB/TC combo.



Dropping a grand on upgrades to solve a problem that does not exist does not make any sense to me. Guys are "fighting high EGT" at 1150-1200*, when they have another 200* to go before even batting an eye at it.



So you bought a wire tap box? All the above is out the window, you are going to have high EGT unless extensive breathing mods are made when running the top levels.



Gauges are another saga. You need fuel pressure and EGT on a bombed 24V. Boost is fun to watch but pretty useless for the most part. If EGT is OK THE BOOST IS TOO!!! EGT is only an issue while towing IMO, you just can't stay in it long enough to hurt a thing empty unless seriously bombed. Even then guys are running in excess of 1800* for up to 20 seconds at a time, for years. Who cares about 28 psi vs 34 psi? There are significantly more guys that would be better off dropping the boost levels they run than guys that need more air. With a wire tap box EGT gauges are mandatory regarless of empty or loaded.



These trucks are large expensive toys that get us where we want to go. There is a distinct difference between "need" and "want" in the modifications needed to safely bomb. Unless going beyond DD3's and a timing box the air situation is fine.

 

[Gary - K7GLD]

LSMITH...





*AMEN!*

 

[SEmerson]

LSMITH...



You sound right on track.

 

[RussW1911]

LSSMITH

You bring up a lot of good points in answering my question and I appreciate that. What I would like to know is where you got the info on how much the stock air intake can handle? I like to know why something works. Some people say "If it ain't broke, don't fix it" I wanna know why it ain't broke and how I can make it better. I am not partial to anything. As I said I am by no stretch of the imagination an expert on this stuff. Thats why I am asking you guys. I almost went out a spent 2500 on a power pack.

My truck will never be on a drag strip I will just tow and be in the Rockies a lot. Lord knows I like the power though.

Wouldn't a better air intake and a better exhaust make the turbo's job easier when I do put my edge comp on?

Save on wear and tear on the engine itself? There are a lot of people with a lot of different opinions I just want to find out what they are and a happy medium before I spen much more money.

Out of all the people that have read these posts so far (over 200 in 8 hours) there are 4 responses. Not very good odds for the guys who are asking the questions, Is it?



thanks again for your info

RussW

 

[Deezul1]

Several of the high performance guys have dynoed 3" and 4" exhaust systems and have found that the 4" system does little good until you reach the 500hp level. The 4" is needed when upgrading to the HX-40 turbo. The above mods are mostly done to reduce very high EGTs and contribute very little HP for the money. Air flow mods are very cost effective as they allow more ful to be added without spending a lot. Exhaust mods are done for different reasons on Diesels than gassers. A good free flow muffler in place of the stock muffler will be a nice upgrade and will go good with a better aircleaner. Before adding any fueling mods an EGT gauge is a must.

 

[LSMITH]

Russ, the reason I know it is not broke is that the EGT is not excessive. When a diesel has enough air the EGT is reasonable, if it does not have enough the EGT gets high. This is always the case. Restrictive exhuast will also raise EGT but not nearly to the extent that starving for air will. Deezul mentioned the dyno testing of the exhuast systems, if I remember correctly the testing was done by Joe Donnelly. You can do a search on his user name and find some of the info, but I remember most of the hard data being in the TDR magazine.



Making the turbo have an easier time of moving the air is not really an issue. The drive force on the exhuast wheel determines the output of the compressor. Lowering the restrictions of the air getting to the compressor will lower the torque on the turbo shaft, but even at 35PSI sustained boost we are not even close to the breaking point of the shaft. Many of these turbos, including mine, have made over 45 psi and are still alive after 110K miles. When I was making 40+ psi my intake system was bone stock as well. The filterminder was showing about 50% on a brand new airfilter. A clogged super duper filter is a lot harder on the turbo than running 35 psi with a clean filter in the stock airbox.



I ran for about 60K miles at 300rwhp. NEVER under any circumstances did I see over 1225 EGT. Now I am about 350 rwhp, and can only reach 1375 at WOT for over 20 seconds and that run was in 90+ degree weather with high humidity. In cooler temps breaking 1300 is almost impossible. I can have any trailer I could reasonably tow at 65 mph in that amount of time, and empty I am over 120 mph by then. I am running the stock airbox with NO holes in it other than the ones it was built with, the boot in between the airbox and the fender is in place, and I am running a fleetguard stock type filter complete with foam over the paper element. It works. I am more of a don't fix what is not broken kind of guy, but I do like to know why it works.



I see in your post that you are going to put an edge comp on. If that is the case this discussion is really pointless. My points above are in relation to a balanced setup, with injectors providing nearly all of the additional power. If you pick the comp you will HAVE to put the airfilter set up, exhuast (straight pipe), and a turbo on if you hope to tow any serious weight on the upper levels. By nature of the box EGT goes up, and is much more difficult to get in check than injectors and a timing box. I owned the predecessor to the comp and sold it. It is not something I would recommend for towing, nor is the comp.

 

[RussW1911]

Thanks Deezul-LSSMITH

OK now thats the type of info I was hoping to get when I joined this club. I appreciate you taking the time to post a long answer and explain that stuff to me. But, Now I am wondering what you would recomend for my situation since I will be towing, it is not the Edge Comp by the sounds of it. I don't tow all the time but am in hte mountains quite often. What upgrades would you say are a must. Keep in mind I would really want more power. Not excessive, Just a kick in the pants I guess.



Thanks again you guys

Russ W

 

[Deezul1]

Sorry I cant help ya on the fuel mods, ya'all have way too valves and it confuses me. Besides I dont know nuthin about them box thingys but lotsa guys here will jump in with good advice.

 

[WadePatton]

[This was going to be response #2 but the server crashed on us. So now it may be redundant, but I had saved it to notepad-so here it is. ]



In case you've misinterpreted anything I said. Not that I'm an expert or anything.



I say it's silly to buy an expensive 4" exhaust-for HP/EGT sake if you're not going over 325 or so HP. A three-incher without the restrictive muffler is plenty. Don't care if you use a muffler just not the stock one, and straight pipe is cheaper.



If you want a 4" for the sound, then fine-way cool.



I say it's silly to buy an expensive air filter when the 40-odd USD BHAF will provide plenty-o-air for sub-400 hp applications. See TDR article last issue.



I'm a fan of the upgrade as necessary and using the economical route. With 325 (est)RWHP and a BHAF and three-inch pipe, I have zero EGT problems and my UFM does NOT defuel at 2700 . But others with the same truck might--enter gauges.



And when I add DD3's to the mix, I know that no air-filter or 4-inch exhaust is going to solve my heat problem, but that a PDR40 probably will.



I will go to 4-inch with the PDR40. If temps are still high, then I'll try the ATS manifold, THEN maybe a high-dollar air filter. If a temp problem still exists then headwork and a cam.



But I doubt all that will be necessary.



smoke to ya!

 

[Pit Bull]

Re: LSSMITH

Originally posted by rwallis



when I do put my edge comp on?

Remember Grasshooper you must keep things in balance.



You will also need to save up for a new clutch from what I understand.



Good information LSmith

 

[LSMITH]

If you are able to change the clutch I would go for a set of DD2's and a Van Aaken on your HO. If a clutch is not in the budget I would look for a set of DD1's or a VA and a set of 275 injectors. You might get away with the DD2's and a boost module with the stock clutch, but it will be awfully close if not over the limit. You will very likely not get away with anything more than dd1's or a set of 275s and a timing box. Lots of guys have run that combo and had no trouble and others have slipped the clutch in short order. Just an EZ or a VA will be a darn nice addition as well. The injectors are easier on the drivetrain, the box will spruce up the low end a little better. A box and small injectors are really nice for overall power and driveability. Larger injectors are really nice for driveability. Hope this helps.

 

[SEmerson]

More impartantly if you are planing a comp. Do gauges and transmission mods. A stock transmission or clutch will not live with a comp alone. With my blue box off I am at about 325 at the wheels. Towing full pedal up a hill is liveable with only a kn replacement filter. I can pull 1250-1300 max. Now with the blue box on I can peg my 1600. But with a comp you can always reduce power to match a liveable egt. But I would say intake side would be a better deal than a 4 inch pipe.

 

[Roger rodbolt]

A question in regard to larger exhaust?

The 2003 ISBe HO makes around 270hp at the rear wheels and Diamler/Chrysler saw fit to install a more expensive 3. 5" and 4" exhaust system. The turbo housing is more restrictive then most of our trucks that came with a 3". As parsimonious a DC is why would they do that?... ... ... ... ... ... . Larry

 

[WadePatton]

Re: A question in regard to larger exhaust?

Originally posted by Roger rodbolt

The 2003 ISBe HO makes around 270hp at the rear wheels and Diamler/Chrysler saw fit to install a more expensive 3. 5" and 4" exhaust system. The turbo housing is more restrictive then most of our trucks that came with a 3". As parsimonious a DC is why would they do that?... ... ... ... ... ... . Larry

three letters: EPA



and on the clutch issue: mine will slip on levels 4 and 5 with stock injectors. I can deal with it, but it will be upgraded.

 

[Roger rodbolt]

Re: Re: A question in regard to larger exhaust?

Originally posted by WadePatton

three letters: EPA



Four letters: nope

 

[Greg Boardman-RIP]

I tow HEAVY... ... ..... I have hauled 20,000 lbs with the stock airbox and the BHAF. That was with the little HY turbo that came on my truck stock. For the first year I only had a V A box. I had a flow through muffler and no EGT problems. I then did the transmission and installed DDII's. Wow. Heat was a serious issue towing heavy. A month later I installed the UFM Drag box. Can you say hot... . Not really. On level 1x1 it fuels even less than stock. That was told to me from the guys at DD and Edge. I did put on an HX 40 and the 4" but I can run over 400 hp now and the EGT's were getting up there on level 5x5. With the New turbo and exhaust I can run uphill, flat footed on 5x5 all day long and stay clear of 1500*. If I hook the trailer up I can put it on level 1 or 2 and go down the road with the cruise on at 65 mph and not exceed 1250* on the EGT guage. That is with 20,000 lbs of hay on a 6700 lb trailer... ... ... . That is HEAVY. Don't be afraid to haul heavy. If you run with the box on lower levels it will still be hotter than stock but not excessive. If you want to have alot of fun, Drop 7500 bucks into a bucket of bolts, turn it up to 450 hp and smoke anything on the road with 25,000 in tow..... Ya ever seen the face of a guy driven a ford when ya pass him at 80 uphill with that much weight?

 

[Whitmore]

One thing I would like to make clear, there is a big difference in air from sea level to say 11k elevation, some of you folks in lower elevations would have trouble with your egt's in the Rockies.



cheers, Kevin

 

[LSMITH]

Kevin, good point. I do know that my EGT comes up faster at high elevation, but peaks EGT's are not a lot different. When you get down in the low country do you see a big difference in peaks?