Power upgrade??

[Bseg]

A good friend of mine who is not a TDR member has a 1993 250 series with an automatic trani and it has 95k miles on it. He wants to know how to get more power out of it.



I own a 97 and know what I need to do to it, but I don't know what can be done with the older 12 valve engines. We came across a document that talks about a screw on the injection pump that can be adjusted to get more power but it isn't real clear as to how much it should be turned. We even looked in the factory shop manual for the truck and they don't even mention this screw.



Can fuel pump be modified the same as in a newer 12 valve engine or would you have to change the injectors to get more power.



His trani has been rebuilt and beefed up so that's not an issue.



He is ready to sell it because it "dogs" on the hills without much of a load. I know how he feels, my 97 isn't much better, but as I said I know what I need to do, just need to get some money together.



Thanks for any help you can give us.

 

[Midnite]

Well, when I got started doing things to my '92, I couldn't afford gauges, so I focused on things that would help EGT and efficiency, etc:



1. Exhaust. I simply replaced the stock muffler with a straight through truck muffler. Obviously a nice 3. 5" or 4" exhaust system would be much better, but I was a little strapped for funds.



2. Intake. I pulled the air filter housing so that the stock air filter wasn't so restricted. I've also now replaced the stock air filter with the slightly smaller version of the BHAF. I think the BHAF would fit fine, and when I go to replace this one, it'll be a BHAF.



Shortly after I cleaned up the intake and exhaust, I had enough money for boost, EGT and transmission temp guages. After gauges, I then installed a set of the Bosch 180HP, AKA "Power Wagon" injectors. Piers sells these, as do other places. Then just recently I was at Piers' shop where I had him advance the injection pump timing to 1. 5mm, and also had him swap the crappy stock turbo housing for a 16cm2 non-wastegated one.



By far, the best improvement was from the injectors, but I definitely wouldn't do those without gauges.



Of course, before laying out cash for goodies, it would be best to make sure everything is running the way it should in stock form. Boost leaks are extremely common, especially in the little rubber boots between turbo and intercooler, and between intercooler and intake manifold.



Mike

 

[AlK]

Bseg,

My advice for your friend is, these trucks can be "bombed" quite fairly inexpensively.

1) get some guages (pyro & boost) being an auto if he does any towing a temp guage for the transmission.

2) instal a set of PW's or POD's.

3) change the timing to 1. 3-1. 7.

4) turn up the rpm's up to 2900

5) a smaller turbo housing (12, 14 or 16) depending on usage.



A good source for parts and excellent advice is Piers at PDR.

http://www.piersdiesel.com/



My truck is a 92 4x4 5spd and with the above modifications there is not much that will pass me going up some pretty steep hills that we have in B. C. I am still running with the stock exhaust and air filter and the fuel has not been turned up.

---

Al

 

[JFitzgerald]

See this page for detailed pump adjustment info. These adjustments will help bring it to life, along with what the other guys have mentioned. Best part is the adjustments are free.

 

[JFitzgerald]

Midnite, how do you like the effects of the timing change? What have you seen in EGT change? The next step for me is to adjust timing and rpm. Peirs showed me what to do at Muncie.

 

[paccool]

Tell him to spend the money and join the club. Thats the best way to find out what to do!

 

[Midnite]

Originally posted by JFitzgerald

Midnite, how do you like the effects of the timing change? What have you seen in EGT change? The next step for me is to adjust timing and rpm. Peirs showed me what to do at Muncie.

Well, he did the timing at the same time he swapped the turbo housing, so it's a little hard to tell, but before, cruising at 60mph on level ground EGT was about 800 pre-turbo. Afterwards it was about 600 - 650.



With about 1000 lbs in the bed, at 60 going up a 6% grade, EGT only dropped from about 1100 to 1000, making me think I was running up against the limitations of my (mostly) stock exhaust system.



Mike

 

[JFitzgerald]

Originally posted by Midnite





Well, he did the timing at the same time he swapped the turbo housing, so it's a little hard to tell, but before, cruising at 60mph on level ground EGT was about 800 pre-turbo. Afterwards it was about 600 - 650.



With about 1000 lbs in the bed, at 60 going up a 6% grade, EGT only dropped from about 1100 to 1000, making me think I was running up against the limitations of my (mostly) stock exhaust system.



Mike

That's interesting. I wonder how much of that change was from the housing swap vs. the timing change. I can't tell what change my housing made because I installed the gauges when I changed the housing. My EGT's were high when I towed 12K last week on vacation. The truck did very well with the weight up the hills, but it's a little annoying knowing there is more power available, and I can't use it because of EGT. Had to watch the pyro closely as it was possible to get into the red real quick going up the hills. I'm hoping a timing adjustment will help lower EGT's. Thanks for the info Mike.