Guy's,

I just bought this '93 w/ 260k... Would you guys be doing mods to a rig w/ this many miles, or should I just leave her alone? Here are a few ?'s for you

1) should I hold off on 4" exhaus until I get a small w/g?

2) if I do the w/g do I need to turn the pump up?

3) I know I am going to pay to play, but what kind of MPG's are you guys seeing with mild mods (intake, 4" exhaust, slight pump tweeks, etc)?

4) any other suggestions to point me in the right direction?


Thanks very much...

Jake

 

absolutely no problem beggining mods a 260k
1, hold off till you have enough fuel to see a benefit
2, don't touch the pump without a Exhaust Temp Gague
3, with slight mods i saw a mileage increase not decrease
4, here's what i reccomend.
a. gagues
b. pump mods
c. lose the K&N for a BHAF (do a search and you'll know why, gasser trash)
d. look into turbo mods depending on overall HP plans
e. injectors
f. olny after injectors will you begin to need the 4" the stockers are too small to bother anything
g. there's much more but you get the idea

 

I won't argue with any of that, but I'll clarify Mark's answer to #2.

You don't need to turn up the pump to see benefits from a small turbine housing. The truck will be more responsive on the low end even if you don't turn it up.

 

Mark,

With my main objective of mileage, what kind of tweeks should I do to the pump?

As for the turbo, think I should just throw a 16cm w/g on my current turbo?

And for exhaust, hold off until injectors, but should I ditch the current muff?

Thanks again for your help... It is a huge diff from the 3 gen (more fun I think)... Thanks... Jake

 

ok, let me clarify. you keep talking about the w/g. here's a list of available housings
9cm w/g
12cm w/g
12cm non w/g
14cm w/g
14cm non w/g
16cm non w/g
18.5 non w/g
21 non w/g

It's the housing size that actually changes not the w/g size. a housing is either wastegated or not. sorry if that's too basic, by some of your comments i wasn't sure if that was all clear.

 

for starters i'm always thinking budget, so let me know if you would like to spend the big $$$, lol.
ok, for mileage, look in the sticky at these things.
1. Timing bump- takes a little low end, gives a better high end + some mileage
2. BHAF- K&N lets too much junk through, when you put the BHAF in do the intake tube mod as well... www.fleetfilter.com can help with the filter and www.airflo.com can get you the rubber elbows you need
3. Exhaust- for starters dump the muffler and look for the crimp over the rear axle, correct if needed (on my wifes truck i cut it after the muffler and cut an elbow out of the tailpipe, made a turndown right after the muffler)
4. change the fuel filter and run some howes meaner cleaner from a T/A if you have one nearby... report back and let us know how the mileage is doing.

once you get the gauges in, run it for a while to get so good base numbers before messing with the fuel settings.

 

For mileage, I'd stick with a bigger exhuast housing (the one you have unless it's a 21cm), bump the timing, do 4" exhaust, and intake. If you want power and mileage, do all of the above, but add some pump tweaks and maybe injectors. You won't need a wastegate until over ~30psi on the stock turbo.

IMO, the 18.5cm housing will be good for highway mileage.

Mark beat me to it...

 

and i'm gonna disagree with you tom on the 4" i really don't think it's needed with the stock IC injectors... not until he throws some bigger sticks in there would it start to benefit him.

 

I dropped 50deg EGT with a 4" tailpipe (have yet to do DP and the rest), so *I* saw a benefit. ALso saw a 100-150 deg drop in my nonIC 91 when I went 4" ANything one can do to help evacuate the exhaust will have a positive impact. How much depends on a myriad of factors.

I dont think you should see less than 20mpg hwy solo. If you do, change all the fluids and filters (ditch the K&N for sure), adjust the valves, and maybe get the injectors checked. All that should cost you is a little time and $2 for new sealing washers. Your stock injectors will get you into the 250-275RWHP range.

I have found the 18.5 exhaust housing best for hwy MPGs also, though I have never run a 16. The 14 did the same thing as the 12- good spoolup, but higher drive pressures and higher EGTs. Havent driven enough to see any difference in hwy MPGs yet.

Check timing, valves, filters, and drive with an easy foot when accelerating, esp loaded. Learn to drive by your pyrometer here. Iy is geared toward the big rigs, but it applies to our pickups as well. You may have to scroll down the list and click on "Driving Habits" and "More Driving Habits" Good info for all.

Daniel

 

Ok, upon further inspection, you will need to click the link. In the side bar, click on "Bruce's horsepower and torque articles", and scroll all the way down. Some of the numbers are old, and being the PT fuel system dont apply to our trucks, but the overall principles are still the same and I found it interesting.

DP

 

Comparing the stock 3" to the 4" DP-back system I just got, I think the 4" will benefit even stock trucks. Not really a power gain, but a drop in EGT's and better spoolup are definitely a likely possibility, as well as a possible gain in mileage. Around the transfer case and over the rear axle the pipe is crushed quite a bit.

 

for price sake, the 3200 spring is only $16 and dropping the muffler helped my STOCK turbo spool up better and I just love the sound...

 

Doubt if it added much power, but I liked the way my tubo sounded after upgrading the exhaust.

 

Thanks very much fellas... I think I will go with the straight exhaust and BHAF for now and then to the 18.5cm w/ the 3200 spring later on.... I think that will do for what I want... I was just trying to get xsomeone to talk me into the Stan's... man that kit looks very nice and it is really resonably priced... Any other info is greatly appriciated...Jake

 

its always nice to direct some one else on how to spend there money. by the way how big of tires you running , the bigger they are usually the less mileage you get. and shinney wheels can't hurt , makes the wind blow by them better. truthfully enjoy your new to you rig its always nice to see someone enjoy it.