How does your rig tow? Maybe I am expecting to much is the problem.

Right now my 93 tows my 5K lbs load no better than my 70 chevy C10 with a good running 350. The chevy power wise actually tows better IMHO. I have checked the air system under pressure for leaks and all is good, lift pump good, AFC set to deep position and pin is free in the pump, BHAF, Fuel screw turned in against lock colar, straight pipe exhuast.

I get a max of 23psi on boost but can't hold it there for a long hill or my EGTs get up to high. Towing it is usually around 18psi and 1100-1200 EGT. It is all the truck can do to pull a 5K lb load up the hills around here.
Towing through colorado was an experience. Couldn't use over 1/2 throttle at all unless I was in 3rd. EGTs headed for the red fast. Ended up in 3rd at 35mph on the way up to breckenridge on I70 going home. Got totaly smoked by my friend in is excursion with a V10 pulling 2K lbs more than me, was 2 miles ahead by the time we got to breckenridge.

I am starting to suspect the advance mechanisim in the injection pump might be the culprit? Maybe something with the turbo? The bearins have some sideplay but the compressor does not touch the housing. I have also been wanting to buy a 12cm WG housing to replace the 18.5 on it now.

I can't turn up the fuel anymore because I already can't use what it is set at, turning it up will just make the EGTs worse.

Or is this just the way most 1st gens tow?

No they don't all tow like that.

My `93 auto tows about 8500 lbs as fast or faster with less heat.

Mine makes 24psi boost, you should be getting more fuel than I am, which makes me think there could still be an undiscovered air leak in the I/C, piping or the boots.


You say you have a straight pipr exhaust, how big is it. My 3" downpipe 4" exhaust with muffler made a noticable performance gain and drop in egt's(don't remember exactly it been a few years).

Where is the BHAF mounted? Is it picking up hot air?

I'm not much help on the pump internals, sorry.

I wouldn't put the 12cm housing on until you find the problem, it won't help with the heat and might make it worse.

Good luck.

What rear axle gears and tire size are you running? Auto or manual trans?

Have you checked your fuel filter? Also do you have a fuel pressure gauge to see if you have enough fuel pressure from the lift pump? Does it smoke a lot when loaded?

It sounds like you have good boost.

I have a Chevy crew-cab with 33-inch tires and 4.10 gears with a 1990 CTD (non-intercooled) and Getrag swapped in. I have pulled 8k pounds in 5th gear with no problem on the terrain around here, which includes some hills but no mountains. By "no problem", I mean A/C on and light throttle, and it does not slow down when I hit a hill on the highway. It has the fuel turned up a little (does not smoke a lot), straight pipe exhaust, and stock air box cut open. The previous owner of my truck pulled a 14k gooseneck with no problem.

I have a friend with a 1992 CTD (hopefully he will chime in here) who has 4.10s and 33's with the Getrag. His truck is totally stock (other than the 33's). He has pulled approx 6k pounds through the mountains of NC into Tennessee with no problem. He recently straight piped his exhaust, but that was after that trip.

I would say that you should not have a problem pulling that load, unless your gearing and tire size are weird, or else you have some sort of problem as you suspect.

Definatly something not right, you should be able to pull the hell out of 5k.

1. Fuel filter
2 Boost leak
3 Valve adjustment
4 Injection Timing
5 Lubes from engine to rear

Start there and I bet you find it.

235/85 stock sized tires with 3.55 gears, getrag trans (read my sig)

Lift pump checked out OK. 5psi at idle and never dropped below 3psi under load.

No blowby and uses almost no oil, maybe 1/2 quart in 7K miles.

BHAF is in the same position as the stock air filter was on an aluminum mount.

Good clean fuel filter.

No smoke once the turbo spools up (1500 rpm with the big 18.5 housing). Hit the throttle to hard under that rpm though and it leaves a black cloud. That is the reason for going to the 12cm housing. On a 5spd truck you loose all your boost when shifting and have to run it up on the govenor to grab the next higher gear with the bigger housings.

I am thinking I will make some more adapters and do another leak down test on the IC. I just wan't to try to eliminate all other possibilities before dumping $900 on an injection pump. With 217K miles maybe its time is up though :(
In the past year it has thrown a couple of fits. Once after a long tow it would not idle, you had to keep your foot on the pedal or it would die. Came out of it after it cooled down. Another time it would not rev up after starting, engine just stumbled and missed until it warmed up.

stright pipe stock exhaust? get a full 4 inch system on there.
mine had all kinds of fuel mods done to it and you can pull loads all day in 100* weather faster than that and it has an auto with no lock up. something not right..

I don't think the exhuast is a problem at this point. Not moving enough air at my current setup to need more. Your 99 is a completely different beast than my 93 though.

Another note about the pump. Not sure if the noise is from the pump, but my accelerator pedal sounds like a tuning fork at times.

Oh, also adjusted the linkage and it is getting WOT with the accelerator.

i had a 92. I am jiMMyCTD on DTR....

if the stock exhaust is crimped over teh axel tube weather it is stright or not can be a big restriction. ditch that 18.5 cm because anything under 2k rpms and it will run hot because its not spinning fast enough...

get teh gov spring in the pump and it really wakes it up and advance the timing of the motor too.

also could be clogged or worn out injectors

Your truck should run better than you are describing stock. Sounds like somebody threw a bunch of hop-up tricks and bits at a poorly-running stock truck.

Randii

When I bought the truck the timing was pushed up quite a bit. It was extremely noisy, about had to wear earplugs when working under the hood as well as being obnoxious in the interior when driving.

I backed it off to 1/16 over the stock mark and did not notice any performance or EGT change from that. I did buy a dial indicator timing tool off a VW forum but have not had the chance to try it yet.

The pipe over my rear axle is not kinked looking to me. I think the system has been reaplaced once as the downpipe is much rustier than the rest. The restrictive spot looks to be around the transfercase if anywhere.

On the injectors the previous owner claimed he had the redone shortly before I bought it, but who knows for shure without having them tested. I can say the truck starts easy and does not have any grey smoke unless it is down around 0 degrees F when you start it.

I did get great milleage towing in colorado since I couldn't give it any throttle :laughing: From grand junction to fairplay I got 16mpg.

Had some nice cool weather for a welcome change so I worked on it for a few hours tonight.

Checked the valve clearances and everything was in spec like it had been done fairly recently.

Made another plug and did some pressure checks. Put a plug with a pressure guage and a valve stem in the first boost boot that would connect to the elbow at the turbo. Put a second plug at a the boost boot disconnected at the intake air horn.
Ran it up to 15psi and it took 1 minute to drop 1psi, there was a small pinhole leak bubling at one of my plugs.
Connected the one boost boot back to the engine and got it turned to minimize valve overlap as best I could. Pressureized it up to 20psi and sprayed the intake all over, the line to the AFC, and air horn. No bubbles anywhere.

What next? About the only thing left I can do here is to check the base timing. Other than that it is send the injectors or injection pump or both in for testing/rebuilding.

From everything that I have read the 12cm exhaust housing is too small if you're going to be pulling alot. You may try to pump up to a 14cm wg housing or a 16cm housing if you're going to be pulling alot.

From everything that I have read the 12cm exhaust housing is too small if you're going to be pulling alot. You may try to pump up to a 14cm wg housing or a 16cm housing if you're going to be pulling alot.

The concensus on TDR and DTR boards is that it is the perfect housing for a mild 1st gen. Remember the 1st gens are governed at 2500 rpm instead of 3200 rpm like the later model trucks are. Mine actually starts defueling at 2300 rpm and the boost falls of to 10psi. With the lower RPM you don't run into the restriction problems of the 12cm housing. From what I have read, they are highly liked and much cheaper than a 14cm WG housing. Also most I have talked to that went from an 18.5 o a 16 noticed no difference at all.

That is down the road though. I have to get it running right stock first.

I have a 92 W250 CTD with a DTT auto trans and feel the same way you do. Towing 5000lbs. I run 15 lbs of boost and egts of 1000 degrees on flat land at 70mph. I have to slow down when I climb any grades because egts climb really fast as well as the trans temp. 70 mph seems to be my max speed because of egt and trans temps. I have many mods on my ctd as well as a new injection pump. I am thinking of ditching the POD injectors for some Bosch 190s hoping that might cool down the egt temps. Empty I can stomp all over my friends 99 powerstroke but when we hook our trailers, he is the winner.

You could also pick up the 3200 govenor spring for your truck, the VEs in the first gens are under $20 for the govener springs. Its east to do to.
The Bosch part number for it is #1-464-650-366
I did this on my '92 and it made a world of difference. Here is a write up on its install. http://www.dieseltruckresource.com/faq/faq.php?display=faq&nr=144&catnr=20&prog=1&lang=en&onlynewfaq=1

Unfortunately I don't have alot of experiance towing with my truck, so I kept help ya with anything other than what i have read on DTR and Cumminsforum.com, I don't go to TDR, I think itst stupid to have to pay $35 a year. But from everything I have seen, if you are going to be towing, the 12cm housing is just too small.

I am so sick of spending money on this thing and constantly working on it that I am about ready to sell it.
Go back to towing with the chevy. Bought it for $750 13 years ago and have rarely had to work on it at all.

Anybody interested..... not after reading this :laughing:

If you sell it what do u think the asking price is going to be?

Would like to get 5500 for it.
Rebuild on rear D70 just done, 2yr old paint job, good tread on tires, club cab with captains chairs, isspro: tach pyro boost, AC, PW, PL, sliding rear glass, cruise, new skyjaker front leafs. I have a bearing and sychro kit for the G360 I wanted to put in as a prevenative measure I would let go with it.
Has 216K miles on it now. Sharp looking old truck.

put the smaller housing and Governor spring on it and you'll be happier. Governor spring is the single best option out there for a first Gen

remember stright pipe doesnt flow more air. and do you still have the corrigated air intake after the filter???

bone stock these trucks were made in the days of 55mph speed limits. i have drivin in a couple stockers. they go 55-60 unloaded or with 6-7k behind them. they are governed for a reason so you can simply floor it all day long. youve turned the pump up...... need more air in and more air out..

you are probably right. I am just disaponted because of now needing to add some cash to my project budget and do more work to it on top of the repairs it already needs. My plans were to get a gooseneck with a camper on the front and put the rig on the back. This thing is not going to hack that load in overdrive up anything much of a hill in 5th, and 60-62mph is tops in 4th gear.

This thing has most of the torque of the trucks made up to 98 but with the low revs the HP is just not there.

Guess I could just go to towing at 55-60 in 4th everywhere.

i have drivin in a couple stockers. they go 55-60 unloaded or with 6-7k behind them.

Wait, what?
I daily drive my bone-stock '92 (4.10/5spd) and routinely do 75-80 unloaded.

Maybe those were older ones with the 727 auto, no overdrive? My dads will do almost 80 on the floor. That poor old farm use truck has 300K hard miles on it.

Wait, what?
I daily drive my bone-stock '92 (4.10/5spd) and routinely do 75-80 unloaded.
sorry. no 410 and the auto with or with out OD pulling grades... yes im sure some slip though with different results...

Don't do anything with the turbo yet. *I* think a 12 is way too small for any towing. It should run a lot harder then it does right now.

$5500......hmmm.....let me go talk to my wife. I could use another first gen.

Michael

You say it tows just as good as your Chevy. how does the towing mileage compare? Probably double in the CTD.
Is it possible with all your pump tweeks your just dumping to much fuel and causing the high EGTs? I had my fuel screw in a turn and a half before my pump was worked on by a pro. I had no problem hitting 1200 EGT and was about 26 max boost. After the pro did his magic on the pump and timing I have trouble getting to max EGT, now can get 27 boost and more power towing. I also have a 4" from the dp back with muffler.

Towing at 70mph the dodge usually gets 14, the chevy gets 10. If I keep it around 60mph the dodge goes up to 15 and the chevy stays about the same.

I wish I had a "pro" that new these trucks to tune it. Seems nobody on TDR or DTR lives very close and knows 1st gens. One guy 230 miles away over in Iowa volunteered to look at it.

The chevy is a 1970 C10 so it does have the advantage of the truck itself weighing 1200lbs less. 350, edelbrock 1406, edelbrock intake, HEI, dynomax long tube headers, dual 2.5 exhuast, 3.42 gears, 31x10.50 tires, TH350 trans. It pulled even better when I had stock height tires on it but when one blew out I had the matching set of 31s sitting in the shed.
Gave $750 for it 13yrs ago when I got out of HS.

I have a 91 non intercooled and it does ok. I did expect a little more so i turned the pump up did stage two injectors and a quick turbo kit on it and now it does awesome it tows my rig with a hd equipment trailer very well and gets 18mpg doing it! Granted it is not a 24 valve with a chip but it gets the job done! Ohh and its for sale $6000 obo

It sounds to me like it's just an older semi worn out truck. I don't know the numbers off the top of my head but the early cummins were not power houses from the factory. I think some people talk up their diesels a lot and some trucks just arn't all that impressive from the factory. I tow with a tbi350/ manual trans chevy that weighs just around 5k with me in it and it tows decent, if it had an additonal 2,000lbs worth of options i bet it wouldn't be any where near as decent of a tow rig.

1st gens are rated at 160/400 from the factory.

Just got off the phone with HT Turbo, said they could fix me up for $820 exchange. Sounds like alot of money to my cheap but :)
Upgrade to a 56mm compressor and 14 or 16mm exhuast housing.

Could do it for $450 just putting those parts on my turbo, but with 220K miles I think it could use a rebuild.

Got my dads 90 out lastnight. My truck is definately more spunky than it is. It has the 3.07 gear ratio with a TF727 though.

Hey, andyr354, if you're interested in trading that first gen for a mildly modified '97 LT1 Firebird, let me know - I might be interested. I've always wanted a Cummins :).

Chris

I put a 93 first Gen drivetrain Nv4500/np205 60/70 4:10 in my 59 Apache Suburban about three years ago. I started out with Stock injectors and a HY35 with a 9cm exh housing turned the pump up a bit. It hauled ass. Since than I've put POD's and gov spring with a HX35/40. it'll pull 8000lbs up Donner Pass going 75 @ 1250 degrees. The BEST MOD I'VE DONE IS THAT $18 GOVERNOR SPRING!!!!! Ok so listen Advance your pump, put governor spring, get that big ass houising off that turbo. remember you need fuel to get boost but you need air to get rid of the heat. fuel is cheap air is expensive.

Hey, andyr354, if you're interested in trading that first gen for a mildly modified '97 LT1 Firebird, let me know - I might be interested. I've always wanted a Cummins :).

Chris

Does it have a gooseneck hitch :laughing:

I am just gonna leave the truck be. I pulls what I need it to pull right now fine in lower elevations. I will just drive 30mph the few times a year I need to pull up passes.

Upgrade the turbo, then you need to upgrade the exhuast, then the trans goes out with the new power, ect.... If I need to pull a bigger load here in a couple of years I will find me a newer rig with a 6spd in it and some more comfort.

I finnaly found somebody to rebuild my getrag. Might drop it out tomorrow if I can find the motivation.