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cranky old fart
01-14-2008, 19:17
I have a stock '94 2500 K with 176,000 miles. It gets around 18 mpg on the freeway at 70 mph. What are the best bang for the buck modifications for fuel mileage and power?
Thanks, Love this site!
Jeff

Jim Faire
01-14-2008, 21:58
I have a stock '94 2500 K with 176,000 miles. It gets around 18 mpg on the freeway at 70 mph. What are the best bang for the buck modifications for fuel mileage and power?
Thanks, Love this site!
Jeff

Just like first aid... make sure it can breathe first.

-Opening up the airbox, removing the snorkle, works good costs nothing.
-3" mandrel-bent downpipe and mandrel-bent crossover, at least 3" exhaust. Costs a bit more, but worth it.
-Turbo-master boost controller... buy for $100 or make your own for $5. It's amazing how well things work when the air can get in and the exhaust can get out.

-Then chip and injectors. Varoom... look out, powerstrokes!

cranky old fart
01-14-2008, 23:35
Thanks Jim,
Is there an existing thread on DIY turbo master boost? Is the snorkle where the air comes into the air box?

93GMCSierra
01-15-2008, 00:12
Another thing you should do, Costs abit of money but worth it, gauges, atleast EGT, and Boost. If you pull any and have a Auto get a tranny temp gauge too.

16gaSxS
01-15-2008, 16:59
Many of our trucks have a Soot Trap some people call them a "Cat" they get plugged up over time and cause power and MPG's to decrease if you replace it or something it will help. Other and I would never suggest this who have inspections on Trucks have "gutted the cat" with good results.

a5150nut
01-15-2008, 19:34
Thanks Jim,
Is there an existing thread on DIY turbo master boost? Is the snorkle where the air comes into the air box?

Snorkel runs from the filter box inside the right fender up to the radiator fire wall. Remove the right battery, you'll find two or three small screws through the inner fender that hold the snorkel in place. Remove them and use pliers to pull the plastic out of the fender.

Robyn
01-15-2008, 20:03
Hello and welcome to TDP

Hmmm Cranky Old fart, very suggestive :D

I have a 95 and it has a 3-1/2 inch Banks stinger exhaust and the kit comes with a replacement for the snorkel in the fender.
The truck also has a turbo master and the ecm has been fitted with a replacement prom.
The truck runs like a scladed dog. Now with the new found power you will find that you will want to let the pony run some as compared to how you used to drive. This is gonna take its toll on the mileage. Ask me how I know this :D:D

The Hiway mileage is still very good at 18-19
My truck is a 95 3500 dually crewcab 4x4 so its empty weight is 7000#
Not exactly a sports car.
My combined city and hiway mileage with the kids dragging the 40 Ft pony hauler around and me using the rig as my daily driver has been showing about 14.

The combined weight of truck and trailer is about 13-14K depending on how many horses they are hauling.

The power is definately there though and the truck will smoke the duals on dry pavement with very little effort. This is very impressive to the young kids with a new pickup that want to runemoff.

I dont need that crap anymore. A quick smokemup usually sends the youngsters fleeing. :eek:

The many vendors that advertise here can help greatly with the needed parts.

Exhaust, intake mods, a prom and definately a set of gauges (Boost and Pyro)

Good luck and have fun

Robyn

cranky old fart
01-15-2008, 20:05
Thanks for the snorkel info.When you say soot trap do you mean cateletic converter?I'm pertty good at turning wrenches but most of me experience is with pre '90's vehicles so I'm kinda slow on the vocabulary. For instance what is the EMC and a PROM?
Jeff

Jim Faire
01-15-2008, 22:05
Hey. For snorkle info, look on Kennedy Diesel's website under tech tips. John has pictures and all that stuff to help with some of these basic mods.

ECM (PCM) Engine Control Module (PCM=Powertrain Control Module). In your 94, it's the "chip" you hear everyone talking about... it controls your electronic fuel injection, your shifting and line pressures, torque converter lockup, timing advance curve, all that stuff.

Chips are also called PROMs - short for E-PROM - stands for Electronically-programmable-read-only-memory... how they MAKE the Chip... they "burn" the programming information onto the chip with a computer.

cranky old fart
01-17-2008, 19:41
I took the snorkel out. I priced a banks exhaust system w/ down pipe. $750 A little spendy for me at this time plus don't you still have to pay someone to weld it for you? Would it be worth it to just start with the down pipe? Is there a cheaper system other than banks that works well?I read the Kennedy tec tips and look forward to modifying my intake tube, it should have the extra webbing in it that they recommend removing
Jeff

Robyn
01-17-2008, 20:14
Ok now I cant say or recommend this but a good downpipe and removal of the cat will help a big bunch. ( if you have to pass inpspection then things change)
The soot trap or Cat will plug up and really cause a lot of backpressure and heat to be retained.
You can gain some nice free breathing by this mod alone.
My 95 with 3-1/2 all the way just runs so nice. The turbo spools right now and you really hear it both up front and out the back.

The stock system without the cat will work fairly well.
A turbo master and a chip will do wonders for the little creature too.

Many of the exhaust systems do not require any welding. These simply hang in and clamp together. This is fine.

You can do it yourself with the rig on stands.

I wouldbe careful if you decide to go 4" as these can be a tad tight in places. My 3-1/2 is close but still fit the stock hangers as though it were meant to be there.
I f I were looking for the last word in performance and was installing a charge cooler, larger turbo and really gonna huff the little monster I would go 4"

The wastegate casting on the GM turbos is the bottleneck on these systems and unless you are going to replace that stuff with a better flowing setup, IMHO the really large stuff is a moot point from there on.

Jochen Woern
01-17-2008, 20:59
Try the Jerry Jardine, PINNACLE POWER EXHAUST System. I got a 4" system from turbo back (down pipe) and it cost me about 300 bucks on eBay, including shipping. It is not the VERY BEST in fit, but certainly in function. It does not need to be welded, comes with all the clamps and hangers and works well for quite a bit less money. The cross over pipe does not come with the system, which I as well purchased seperately on eBay.

I was not up for paying Kennedy's or Banks prices either, so I went with the PINNACLE SYSTEM and I am happy with it.

cranky old fart
01-17-2008, 21:11
Well I saw Kennedy has a system including down pipe for $450. Has anyone installed this system?

Artworks
01-18-2008, 06:28
I installed Kennedy system on my truck a year ago, works great, had trim one pipe a bit , but no big deal, as long to remove old system as to install new. nice clamps . I still have the stock cross pipe however. I have had great service from Kennedy from anything I have gotten.

Kenneth
01-18-2008, 18:13
I would go with Kennedy just for the mere fact that it is a 3 1/2" exhaust rather than a 4". I also installed a 4" Pinnacle exhaust and I got what I paid for. It is a decent exhaust, but I had to do some fabrication to get it to fit. From everyone I have talked to the Kennedy exhaust just bolts right on. Anyway, after having installed a 4" exhaust it is quite a tight fit and I certainly don't see it necessary for a 4". If I had to do my exhaust again, I would pay the extra money for a Kennedy exhaust.

Don't get me wrong, I don't hate my pinnacle exhaust, I just wish I would have gone with a smaller and better quality exhaust. There have been quite a few people who have bought the pinnacle exhaust and love it and never had any problems with it. But there are also a lot of people who have had to do some minor fabrication to make their's fit as well. So I would say it is hit and miss with Pinnacle. But they are cheaper, but just remember you get what you pay for.

sturgeon-phish
01-19-2008, 12:52
I went with the Kennedy system. Went on NICE and EASY. I had to cut one pipe down. The stainless band clamps from Kennedy are a better quality than a crimping exhaust bracket, but it makes adjusting and later removal of the exhaust easy becuse the pipes do not get deformed.
IMHO anything beyond 3 1/2" for most of our modified trucks is for show.
When installing the downpipe, hammer down the flange where the cab and floor panel meet, you will see the spot when you start hanging the system, to provide a little more clearance in a tight spot.
The cut off and hang time were about equal. I spent a couple hours just twisting and adjusting to ensure max clearance from body / frame parts.
Everything I needed came with the kit and there were no trips to the parts store. That and the better clamps make it worth the extra $$$$
Jim

Jim Faire
01-20-2008, 09:14
I took the snorkel out. I priced a banks exhaust system w/ down pipe. $750 A little spendy for me at this time plus don't you still have to pay someone to weld it for you? Would it be worth it to just start with the down pipe? Is there a cheaper system other than banks that works well?I read the Kennedy tec tips and look forward to modifying my intake tube, it should have the extra webbing in it that they recommend removing
Jeff

Hunt around a little... you should be able to get a 4" exhaust system for about $375 from either Warpspeed or Jardine, or $450 from Kennedy or Heath Diesel. All are pretty good, mandrel-bent downpipes, flow-through mufflers, and you just clamp them together - don't need a welder, 90% of the time, just a sawzall to cut it off.