Ponies Rustled?! What the ????

[Mike Ellis]

Being somewhat under the weather healthwise and not feeling up to fooling with the engine lately, I took my '97 3500 5 spd (3. 54 gears) up to the Cummins facility in Fort Worth this week and had the valves adjusted. I had noticed a peculiar sound at heavy load a few times, kind of a clattering tapping noise, and asked them to check out my lift pump etc. to make sure it was fueling right (no gauge yet).



The Cummins guys seem to do good quality work, the valve adjustment was done quickly, they steam cleaned the engine along the way and put new gaskets on the covers. The gaskets they used were gray, I thought they were supposed to use the black ones but the service guy said no difference. Hmmm.



Anyways, they told me they ran the truck on the dyno to check out engine under load, didn't see anything unusual and thought the engine was running fine. According to the service manager, "It put about 162 hp to the rear wheels, that's about what we expect from a 215hp manual so it looks like everythings fine. "



I would have expected #'s in this range for an auto, but seem to recall stock #'s for the 215 manuals to run between 180-200 hp or so. When I told the guy it seemed low, he said that was what they normally saw for a 96 or 97 5spd. The dyno sheet didn't show torque, rpm, or anything else except 162hp at 51mph. This translates into about 2000rpm in 5th or 1500rpm in 4th based on my MkI eyeball, don't know what gear they used, guy didn't recall but said probably 4th as it is 1 to 1.



Do these numbers sound reasonable for a stock '97? Any info is appreciated...

 

[Steve Campbell]

Someone with some brains will respond and clear this up for you.



Having no brains:{ , I think (contradiction in terms) that the HP for the RPM's they were turning your engine were pretty good. There is some formula floating around out there that allows you to compute torque from Hp and visa-versa.

 

[illflem]

The HP to the rear wheels is lower than the engine's rated HP. Your numbers are right in there for a stock truck.

 

[Don M]

Mike,



I know how ya feel about being a few HP short on the dyno.

Actually if the truck was run in 4th gear your numbers may come up a little bit lower than it would in 5th. The Cummins likes the extra load from the overdrive in 5th to make a few more HP on the graph. The Cummins dyno's are notorious for showing a lower number than the DynoJets and Mustangs that performance centers use. Plenty of guys have complained about the lower readings in the past. All that being said you are very close to what most other trucks read at Cummins with that config.



I watch your posts and when I heard from another member that you were coming to the D/FW dyno event I was walkin around all day trying to find you. I either missed ya somehow or you did not make it out. I hope you can make it to the next event and we can meet. I might have some free advice for you on your truck too. Course, we all know what free advice is worth.



Hope you to get feeling a bit better soon.



Oh, the grey cover gaskets are great. They come in the marine gasket kits and are of top quality.



Don~

 

[fest3er]

Originally posted by Mike Ellis

... According to the service manager, "It put about 162 hp to the rear wheels, that's about what we expect from a 215hp manual so it looks like everythings fine. "

Cummins here in VA told me they were seeing 172 RWHP from my '98 12V auto, that it was 'rather strong': they don't usually see more than 130 or so in an auto. At that time, I believe I had only a K&N fitler and Amsoil. Oh, and 215HP injectors. Hadn't done anything else.



I'd say you're in the ballpark, and probably closer to the pitcher's mound than you might think.



Fest3er

 

[HoleshotHolset]

Mike Ellis,



So... did adjusting the valves get rid of the clatter or what?



Curious... as per usual,

Matt

 

[KRoaden]

I too am interested about the valve noise. I just recently adjutsed mine and it did not change the noise much if any. I very interested!!!Oo.

 

[Todd T]

with a manual transmission and that huge ring gear in the Dana 80.



it would be conservative to figure 20% drivetrain loss. that would put you at 172BHP.



and 20% IS conservative... throw in the long bed with a split driveshaft and a Dana 80 (which is what you should have) its even more.



good job!!

 

[Bad340fish]

Don't forget the dual wheels... those will throw some more % in there I imagine. Those wheels are by now means lightwieght

Clark

 

[Mike Ellis]

Clattering Noise

Holeshot,



I haven't had the truck in front of a heavy trailer yet since valve adjust so I don't know if the noise is gone now. I drove down to Houston Monday night, came home Wednesday, and during the drive I couldn't tell any difference from the valve adjustment at all.



I thought this was interesting because the service tech had noted on the form that several of the valves were "pretty loose", both intake and exhaust. I thought that if this were the case there might be some noticeable difference in performance or sound or such, but I sure haven't seen any. Maybe I will be able to detect some difference under heavy load, or perhaps after I've run several tanks through it I will see a difference in economy.



My truck gets around 20. 5 mpg unloaded on my usual driving routes around these parts, stop-light antics don't seem to affect it much at all - can drive sedately or energetically around town and it doesn't vary much that I can see. 22-23 mpg is attainable at slower highway speeds (60 or so), towing mileage is pretty good too at 12-14 mpg with our large Sundowner horse trailer. I have found this sort of behavior very interesting, it is the first vehicle I have owned where driving habits don't have a very strong effect on mpg.



The old Cummins seems to be a pretty solid powerplant. Didn't seem to be phased by those loose valves.

 

[HoleshotHolset]

Mike,



I just did a May-'01 thru current fuel statistics analysis..... I've put on 15,000 miles... . spent ~$1000 on fuel and got 18. 39mpg... . that's the average. Only did a little bit of towing and the rest is unloaded driving it like a commuter vehicle. I use the soot pedal quite a bit and the only thing that really kills the MPG is the speed I travel on the highway... keep it under 75 with 4. 10's and you'll do fine. Recent trip to PGH, PA was 20mpg all-highway... so I'm happy.



As for the valves... . mine are probably unadjusted like yours used to be... . waiting for the courage to adjust them and advance my timing.



Thanks for the info... .



Matt