Everyone has posted all kinds of things about exhausts, turbos, gauges, pyro this and injector that.

I need a "Quickie CTD mod list for dummies"!

I don't tow much heavy stuff, so I'm looking for mostly quick and inexpensive stuff to make it run better, easier and more economical overall.

My truck is an unmodified '91 intercooled, 4 speed OD, 4x4, posi-traction (3.5 gears?), 3/4 ton, regular cab with 201,000 miles. To the best of my knowledge the KDP has not been secured.

Thanks for the patience!

Denis

 

First off you need guages(tach,pyro,boost) so that you don't roast the engine. It can be pricey depending on your budget but its a must before you start.

Next turn up the pump. There are good directions in the tech facts about how to do this.

After that its up to you , a 16cm turbo housing does wonders and somwhere along the lines a 4" exhaust system will be needed to get the full potential of the other mods as well as a new gov spring.

By the time you do the guages, turn up the pump and replace the turbo housing you will have a good idea where to go from there.

 

The single best thing you can do is change the turbine housing. Since you're not towing heavy stuff, I highly recommend the 12 cm housing I'm using. When I changed the housing, it was like getting a new truck all over again. The 12 cm's can be got pretty cheap (mine was free).

 

Cool, thanks!

How pricey are the gauges, and where can I get them?

I'll check the tech files for the pump (pump?).

If I should go with either the 12cm or 16cm housing, what is the standard housing? What does a stock '91 intercooler have?

I'm surprised neither of you has suggested changing the airfilter to some K&N type!

 

I don't like oiled cotton unless a paper filter big enough to handle the flow is impractical. Get a BHAF if you want more air. You should have a 21 cm housing on the truck now, it is horribly laggy. The 16 is a direct bolt-in, the 12 cm is about 1.5 inches longer, it will require moving or shortening the downpipe. The gauges are available from pretty much every vendor who advertises on DTR. I put the gauges in my work truck for less than $200, but I didn't need a pod.

 

DOH! The airfilter is a good point, I just took it for a given.

I tow with my truck so I want with the 16cm. Stock they come with either 18 or 21cm. Smaller housing gives you less lag time, more boost(higher psi) and higher EGTs(Exhaust Gas Temps, this is bad thus why you need guages).

Turning up the pump, refers to upping the settings on the injection pump. These trucks are seriously de-tuned from the factory and with some adjustments to the injection pump you can really increase the perfromance, and its FREE!

See here:
https://www.dieseltruckresource.com/...n&onlynewfaq=1

 

OK. Sorry for the ignorance, but what is a BHAF, and what is the "pod" you didn't need?

I understand the benefits of a smaller housing, and also the injection pump now that IT is spelled out.

Also, I see the need for the gauges if there are higher egt's, but what do you do about them?

 

I bought my A pillar gauge pod (to hold the gauges) and gauges from dieselpage.com

I like the 16cm^2 housing, but it still has a fairly high boost threshold (minimum rpm --cfm-- that it will produce boost at). That does equate to some lag depending on the driving situation. A wastegated 12cm^2 would be sweet.

 

BHAF = "Big Honkin Air Filter"

I run a K&N "naked" -- took the air box out, and hang the filter from the fender. It would be better to make a cold air intake, but I haven't gotten to it yet.

A smaller turbine housing will lower EGT's at lower engine RPM's, but raise them at higher rpms. The 16cm housing is big enough that you should never have a top end EGT problem, unless you are really dumping fuel into the engine at over 2700 rpm. I really like my 12cm housing, but don't run the truck with much of a load. It reduced my EGT's by almost 400 degrees pretty much across the board.

The cheapest & easiest pump tweak is to take the cover off the AFC, rotate the eccentric so that the deepest part of the notch is facing forward, and put a thinner stop washer in to increase eccentric travel. All it takes is a large flat head screw driver, and an open end wrench (to un-do the signal line to the AFC).

Good luck and have fun!

 

You can get gauge pods for the pillar or the dash. Basically they are plastic gauge mounts that allow you to mount the gauges up where you can see them without an ugly mess. They run from $30 to $50 depending on where they mount.

 

BHAF - Big Honkin' Air Filter! DOH!

Pod - got it.

Do most people go for dash or A-pillar mounts?

Mostly, I'll be drivng the truck without a load at all. I might carry a motorcycle or two on occasion, and every now and then I'll pull a car hauler, but that's about it. Would the 12cm housing be better for this, then?

On the highway, I'll probably rarely run the truck at over 75mph. The 12cm will be best for this as well?

Before I mess with the pump, I take it I should get the gauges, eh?

Thanks, guys, for your patience!

Denis

 

One more thing, will this negatively affect the 19.5mpg I'm getting on the highway?

Denis

 

If you don't plan to add injectors I think you will do well with a 12 cm. My in-town mileage went up about one mpg after the housing swap, highway mileage is the same. I think more guys use the pillar mount, it isn't as obtrusive as the dash pod. The party line here is gauges first - Alec will dope slap me if I get out of line again...

 

Denis,
One more thing, will this negatively affect the 19.5mpg I'm getting on the highway?

Theoretically no it should not affect the 19.5mpg in fact it should go up, but - that all depends on YOUR RIGHT FOOT .

The problem is we all have the tendency to use the extra found power when we really don't need it .

Remember the faster and better your truck runs the lighter the load it has to carry (wallet).

Happy dieseling!
Al

 

Thanks for the info, guys! That is good news on the mileage. With those mods, the new tires I'm going to put on it, and the switch back to normal summer fuel without additives, it looks like 21-22 might be possible on the highway! I'll do the gauges first, then the housing swap and pump adjustment. Air filter too.

Whew hoo!

Denis