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Topic: 8.3 Cummins, verses 3126 Caterpillar (Read 4155 times) previous topic - next topic

8.3 Cummins, verses 3126 Caterpillar

So I finally got to compare. This should really start some fun. Our 3126 Cat is 300HP, 8.3 Cummins is 325 HP.

I constantly get asked how the Cat does in mountains (like they think it's a turd). My answer is fine. 2 weeks ago, drug our 22' 3800 lb enclosed race car trailer with 4K lbs of race car and junk over the mountains into Anaconda Montana. 8,000' altitude

Personally, I think the extra weight, just makes the computer add more fuel and boost. But what do I know. But today, drove my buddies 98 40' U270 8.3 over to his shop. No resonator, got some razzo chip, and newer aftermarket turbo, and to be honest (granted it's 4' longer) I didn't feel any difference in torque or power to our unloaded coach.

I'am a drag racer, use to being 8 seconds at 150 MPH in the 1/4 mile, so I would be the 1st to complain about power. I have no complaints. Was even told the Cat can be wicked up to 325 HP. Don't even care.

I smile with mostly 11 MPG towing wrangler, and this trip with trailer netted a 8.5 MPG average. Mountains and all. So not putting down the 8.3 Cummins, if that was the choice I had, it would have been fine.  From all I read, and talking to friends, they both have emotional issues at times.

Now a 450 HP red top, in a 36' I might change my tune....LOL

This post was just for fun, and BTW, the Cat in 1997 cost a bit more, and increased the warranty from 100K miles, to 200K miles. But of course that didn't help me with my drama's.

14K miles and counting. Zero smoke or oil usage. Not one spot on the shop floor.

Chris

Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #1
Both mechanical engines are good. Parts for the Cummins are less and perhaps fewer issues when the 8.3 first came out. Some new RVs are squeezing 380 hp out of the 8.3 but I'm not a fan of their Celect electronic injection. Think the mechanical engines are a toss up with both providing reliable power. They get a good B+ to me. Nothing wrong with a 3208 either. Good in a coach or pickup truck.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #2
Last thing I remember doc I started to swerve then I saw the cat slide into the curve.
Dub McBride 1996 270

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #3
Sure seems like Cat was a little conservative on hp ratings, Cummins optimistic.  On the mechanical engines.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #4
I was quiet surprised at the get up and leave this little mechanical 8.3 had when I first got into it from a stop and it kept pulling hard until I quit at 72 or 3. With the cruise on heading up a mild to medium grade it pulls its butt off. I don't mean speed wise but you know the sound and feel of a diesel when it's putting out peak power and you know it's giving its all..Well pleased with the want to the little mill has.. It fits a mid size coach like I have quiet well. Never drove a 3126 but with everything up to snuff it should be plenty in a no slide 36 ft coach.It may be like the little 1693    325 hp cat had out in the 70's.. worked more like a 400 horse and the 425 1693 pulled as hard as some of the 550's and a few of the 600's I've had.. Some of the cats were stronger than their displacement numbers would imply.
Dub McBride 1996 270

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #5
Having worked on both engines and done performance upgrades to them (in a past life/job), I can tell you the Cummins is easy to work on, modify and get power out of.  If that's a 3126E, it has the HEUI injectors which are expensive and limited on what you can do.

My FIL has a '02 FT 36', 2 slides with the ISL 400.  We have the '03 FT 38' with tag axle and 2 slides, ISM 450.  He can usually just pull me on grades.  If I'm on the mat, he's got a few mph on me at the top.  Not sure what the weight difference is, but it must be enough to let the smaller engine and trans run us down.  Man I gotta get that pyro installed so I can put in some injectors.  :)
Keith
2003 U320 38' #6197

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #6
Having worked on both engines and done performance upgrades to them (in a past life/job), I can tell you the Cummins is easy to work on, modify and get power out of.  If that's a 3126E, it has the HEUI injectors which are expensive and limited on what you can do.

My FIL has a '02 FT 36', 2 slides with the ISL 400.  We have the '03 FT 38' with tag axle and 2 slides, ISM 450.  He can usually just pull me on grades.  If I'm on the mat, he's got a few mph on me at the top.  Not sure what the weight difference is, but it must be enough to let the smaller engine and trans run us down.  Man I gotta get that pyro installed so I can put in some injectors.  :)
Have you bought any components from Pittsburg Power.. We just bought a 12 liter Detroit with one of their exaust manifolds and Turbos and it will knock a hole in the atmosphere. It has been tuned and I sent it in today to have it tuned close to specs. The driver that is going to drive it has no business with that much power. If I were still driving I would leave it be but not for just any hired driver. Been there done that.
Dub McBride 1996 270

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #7
I have not.  We focused on the high performance pickup market...7.3, 6.0, 6.4 Power Stroke, 5.9 and 6.7 Cummins and 6.6 Duramax.  We dabbled in the 8.3 Cummins, DT466, DT444 and Cat 3126E engines.  Didn't play with anything larger.
Keith
2003 U320 38' #6197

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #8
Having worked on both engines and done performance upgrades to them (in a past life/job), I can tell you the Cummins is easy to work on, modify and get power out of.  If that's a 3126E, it has the HEUI injectors which are expensive and limited on what you can do.

My FIL has a '02 FT 36', 2 slides with the ISL 400.  We have the '03 FT 38' with tag axle and 2 slides, ISM 450.  He can usually just pull me on grades.  If I'm on the mat, he's got a few mph on me at the top.  Not sure what the weight difference is, but it must be enough to let the smaller engine and trans run us down.  Man I gotta get that pyro installed so I can put in some injectors.  :)

It's a 3126 (just a bigger C.I. 3116)....1st gen has no letter. Next gen is 3126 B (1998), then the E's came. Similar to the C17
Yes it has a HEUI pump, I love the design. Hated it at 1st. Makes sense to me.

When I look at that tiny little 8.3 block and head sitting in the huge engine bay, my 3126 looks like a BB. Big industrial engine, designed to run all day at lower RPM's, grunted.

Again, not knocking 8.3's, but their life span starts shorting when you start boosting them. We had a guy in the area, Dr Diesel years ago. He had a new 8.3 FT in like 1998 he bought at our store in Coeur d Alene. He was the go to guy big dog guy boosting everyone's Cummins in the area. He is long gone, and they towed his new Foretravel in blown up to get warranted, after he pulled all the hot rod stuff off.

Many cracked heads and blocks with stock 8.3's.A guy drove one to Yuma from here to leave for good. Dumped tons of stop leak, and gallons of water in it. It made it barely. It's now a permanent winter home...LOL

In a drag car,or Hot Rod, I build them to the hilt, drive the wheels off. My street driving stuff, I tend to leave stock. I personally don't care who passes me, or makes it to the top 1st, or throw's beers cans at me as they pass by. I just turn the stereo up, enjoy the mileage and relax.I actually tend to back off, and not push it, just let it do it's thing. I like longevity.
Cheers
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #9
Sounds like you're talking about Barry Sadler.  Yeah, he's gone now.  He was one of the first to do some upgrades, but he was a scam artist and just did junk work.  Move the rack, turn the towers and slide the plate forward.  No finesse.  Many after him did a way better job.  The place I worked at was the first in the 11's with a full size 2500 pickup, then first to build a full size drag truck too.  Only went 9's before the program was shut down, but with LOTS of potential.

Anyway, most of the engine have a good bit on the table if you care to do it right.
Keith
2003 U320 38' #6197

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #10
Have you bought any components from Pittsburg Power.. We just bought a 12 liter Detroit with one of their exaust manifolds and Turbos and it will knock a hole in the atmosphere. It has been tuned and I sent it in today to have it tuned close to specs. The driver that is going to drive it has no business with that much power. If I were still driving I would leave it be but not for just any hired driver. Been there done that.
Dub,

What kind of Detroit was it? 8-92, 60 series or a newer DD13?  Now if we could have Detroit's slick DT12 transmission.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #11
I often get bugged at the lights by those pickups when I drive my Vette. Along with youngsters driving Dodges and foreign cars Some of the pickups seem peppy but they smoke like the devil. No harm in having fun but the streets are to crowded to open a throttle, unlike when I was 20 something. It's all ok but most have more power than skill.
Dub McBride 1996 270

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #12
60 series, one of those tuned to hot to be slip seated. It does have a couple quality components bolted on. It will be adequate set at specs.
Dub McBride 1996 270

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #13
I was driving back across the U.S. in a damaged PU with an almost new mechanical "Dealer's Diesel" 7.3 turbo in it and stopped for fuel just west of Salt Lake City. There was a Dodge PU with a 5.9 and a very long aluminum horse trailer behind it. I followed him on to the highway where we both used PTM. He put out an incredible smoke screen and was far in the distance in 30 seconds. Fast was an understatement. But, a couple of miles before I pulled into Winnemucca, there he was by the side of the road with his hood up looking very unhappy.

I know our 6-92TA Detroit generally puts out about 535 hp in a boat but some buy the 625 hp version for the fast boats. At this rating, you just have to sign the check ahead of time with the amount blank to be filled in by the shop.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: 8.3 Cummins, verses 3126 Caterpillar

Reply #14
What does PTM stand for?  PTM (Please Tell Me). :D
2000 U320 mid entry  #5688
2006 Jeep Liberty


USMCR retired
SDFD retired
FEMA US&R TF8