Post by chaplain on Nov 7, 2010 0:05:51 GMT -6
Hey Guys,
I just thought I'd post a few things I learned while trying to find a few more horses for my 1994 Silverado 4X4 K2500 350 c.i. w/3.73 gears.
As some of you may have seen in some of my posts in the "Help" thread under the "Wanted" section, I have been trying to get some more performance in my truck to pull a monsterous toy hauler camper. The camper weighs in fully loaded at 9000lbs. give or take a couple hundred lbs. That's a pretty good load to haul down the highway with a 3/4 ton pickup I don't care what anybody says.
While I still need a couple of things to make this job as easy as possible, (like air bags to assist the leaf springs, maybe a bigger radiator and water pump and or electric fan to assist in cooling) I have I think solved the power issues. And I didn't have to spend an arm and a leg nor did I have to tear down the engine for a rebuild to replace the cam and rockers and do all the high performance mods that go into an engine rebuild to gain the power I needed to be able to pull the trailer without working the truck to death doing it.
I did it all with simple bolt on mods that were very inexpensive and very easy to install. I not only got the extra power I was looking for, but I improved my gas mileage substantially. I wasn't looking to gain hundreds of HP, I only needed a small increase in HP and torque to get the job done. My gas mileage in town has improved by about 8 mpg and closer to 11 on the highway. That's without the trailer on the back. However, I towed to Indy for the bracket finals and I got a true 10 mpg round trip. That was before I had completed the mods to the truck. On the Indy trip my muffler had a small split in the seam around the end cap that grew to a very large split during the trip, and I still had the catalytic converter in the system.
So what did I do to get the increases in power and gas mileage? First I bought a ThermoMaster computer chip from Hypertech and the 1600 thermostat that Hypertech says is needed for this chip to work. I went ahead and ordered their thermostat, but I had already put one in I got from a NAPA store near my house. I could actually feel the difference in the seat of the pants immediately and the mileage increase was obvious with just that one mod. Cost was about $210.00 including shipping. It took me about 20 minutes to install the chip. The very next day I installed a cold air intake system from K&N filters. I could also feel that mod immediately in the SOP. Cost was about $90.00 and took me about 1.5 hours to install it. I then towed to Indy and found that the truck was pulling the trailer A LOT better with just those mods. When I got back I had the exhaust system replaced using a FlowMaster 40 series muffler with 3 inch inlet and outlet and 3 inch pipe from the Y all the way back. We eliminated the catalytic conveter since this year truck doesn't have to go through the emissions testing here in IL anymore. The truck sounds like it has dual exhausts, but the muffler is way back under the bed and the pipe exits in the stock location so the noise inside the cab is pretty quiet, (you can hear it more than before, but you don't have to yell to talk and you don't have to turn the radio up to overcome the exhaust system sound.) This mod made a HUGE difference. I know an exhaust system upgrade will make a difference all by itself, but I think that it is making the other mods perform to their maximum levels as well. The cost was about $250.00 and the shop had the truck for about 3 hours.
Each modifcation made an immediate difference that could be felt VERY noticably. But the complete package has produced way more than I ever expected and was not only inexpensive compared to a rebuild, but was very easy to do.
Bottom Line:
Hypertech Thermomaster Chip $210.00
K&N Cold Air Intake System $ 90.00
Flowmaster Exhaust System $250.00
Total Cost $550.00
Estimated HP Gain
Hypertech Thermomaster Chip 20 – 25
K&N Cold Air Intake System 10 – 12
Flowmaster Exhaust System 15% gain 39.75 + or – 5 hp
Truck was listed by Chevy @ 235 HP stock. I don't know what RPM they took that reading at, but I think that's a little low to start with.
Add the Chip and Air Intake system and you get about 263 HP
Add the approx. 15% gain from the FlowMaster System and that brings it up to about 304.75 HP
That’s an increase of about 69.75 HP all for about $550.00 give or take $20.00 or so!
I know that sounds too good to be true, and I was skeptical as well until I went to the Internet and got some figures from others who had done virtually the same kinds of mods to their trucks or cars. I took the advertised increase from the companies who make the products and used the lowest increases they had for each mod and then looked at the dyno’d real increases I found on the Web for the same mods. My figures are based on the LOWEST increases I found for these mods, so I figure I’m pretty close. I would still have doubts except that after each change I made, I could actually feel the difference substantially. After the last race at Gateway I towed the trailer home for the first time with ALL of the changes in place. My RPM are down nearly 500 RPM at 60mph. The same hills where the truck used to struggle somewhat are now conquered with ease. One hill in particular is VERY steep and about a quarter mile long. The truck used to stay in first gear and work VERY hard to get up the thing. It now shifts into second gear after about 200 feet and just walks right up the hill at about one quarter throttle, running at about 35mph and about 3200 RPM. I used to have to mash down on the gas peddle and literally scream the engine just to get up this hill.
I still don't know if the truck will run as cool as I want it to in mid summer at 900 plus, but I know I have solved the power issues. I would highly recommend that anybody needing a little boost in power or mileage or both, in their tow vehicle take a good hard look at what I've done. For the price, it's a no brainer as far as I'm concerned. By the way, on the trip to Indy the air temp was around 800 or so and the truck temp was never over 1750 even going up some of the longer grades or running headlong into a pretty strong head wind as we did on the way home.
I hope this helps some of you guys out, if you're having some of these issues with an older truck, or a new one for that matter. Several people on the websites where I got some of the info that I used to make the decision to do this were more than skeptical about any of these changes doing much at all to make a difference. Well I am here to say Bull Sh** to all the nay sayers. This really did work on my truck.
My next project is to get the rusted areas cut out and new panels put in and paint the truck to match the trailer. That one will take me a while because of $$$$. But I'm a patient man.
I just thought I'd post a few things I learned while trying to find a few more horses for my 1994 Silverado 4X4 K2500 350 c.i. w/3.73 gears.
As some of you may have seen in some of my posts in the "Help" thread under the "Wanted" section, I have been trying to get some more performance in my truck to pull a monsterous toy hauler camper. The camper weighs in fully loaded at 9000lbs. give or take a couple hundred lbs. That's a pretty good load to haul down the highway with a 3/4 ton pickup I don't care what anybody says.
While I still need a couple of things to make this job as easy as possible, (like air bags to assist the leaf springs, maybe a bigger radiator and water pump and or electric fan to assist in cooling) I have I think solved the power issues. And I didn't have to spend an arm and a leg nor did I have to tear down the engine for a rebuild to replace the cam and rockers and do all the high performance mods that go into an engine rebuild to gain the power I needed to be able to pull the trailer without working the truck to death doing it.
I did it all with simple bolt on mods that were very inexpensive and very easy to install. I not only got the extra power I was looking for, but I improved my gas mileage substantially. I wasn't looking to gain hundreds of HP, I only needed a small increase in HP and torque to get the job done. My gas mileage in town has improved by about 8 mpg and closer to 11 on the highway. That's without the trailer on the back. However, I towed to Indy for the bracket finals and I got a true 10 mpg round trip. That was before I had completed the mods to the truck. On the Indy trip my muffler had a small split in the seam around the end cap that grew to a very large split during the trip, and I still had the catalytic converter in the system.
So what did I do to get the increases in power and gas mileage? First I bought a ThermoMaster computer chip from Hypertech and the 1600 thermostat that Hypertech says is needed for this chip to work. I went ahead and ordered their thermostat, but I had already put one in I got from a NAPA store near my house. I could actually feel the difference in the seat of the pants immediately and the mileage increase was obvious with just that one mod. Cost was about $210.00 including shipping. It took me about 20 minutes to install the chip. The very next day I installed a cold air intake system from K&N filters. I could also feel that mod immediately in the SOP. Cost was about $90.00 and took me about 1.5 hours to install it. I then towed to Indy and found that the truck was pulling the trailer A LOT better with just those mods. When I got back I had the exhaust system replaced using a FlowMaster 40 series muffler with 3 inch inlet and outlet and 3 inch pipe from the Y all the way back. We eliminated the catalytic conveter since this year truck doesn't have to go through the emissions testing here in IL anymore. The truck sounds like it has dual exhausts, but the muffler is way back under the bed and the pipe exits in the stock location so the noise inside the cab is pretty quiet, (you can hear it more than before, but you don't have to yell to talk and you don't have to turn the radio up to overcome the exhaust system sound.) This mod made a HUGE difference. I know an exhaust system upgrade will make a difference all by itself, but I think that it is making the other mods perform to their maximum levels as well. The cost was about $250.00 and the shop had the truck for about 3 hours.
Each modifcation made an immediate difference that could be felt VERY noticably. But the complete package has produced way more than I ever expected and was not only inexpensive compared to a rebuild, but was very easy to do.
Bottom Line:
Hypertech Thermomaster Chip $210.00
K&N Cold Air Intake System $ 90.00
Flowmaster Exhaust System $250.00
Total Cost $550.00
Estimated HP Gain
Hypertech Thermomaster Chip 20 – 25
K&N Cold Air Intake System 10 – 12
Flowmaster Exhaust System 15% gain 39.75 + or – 5 hp
Truck was listed by Chevy @ 235 HP stock. I don't know what RPM they took that reading at, but I think that's a little low to start with.
Add the Chip and Air Intake system and you get about 263 HP
Add the approx. 15% gain from the FlowMaster System and that brings it up to about 304.75 HP
That’s an increase of about 69.75 HP all for about $550.00 give or take $20.00 or so!
I know that sounds too good to be true, and I was skeptical as well until I went to the Internet and got some figures from others who had done virtually the same kinds of mods to their trucks or cars. I took the advertised increase from the companies who make the products and used the lowest increases they had for each mod and then looked at the dyno’d real increases I found on the Web for the same mods. My figures are based on the LOWEST increases I found for these mods, so I figure I’m pretty close. I would still have doubts except that after each change I made, I could actually feel the difference substantially. After the last race at Gateway I towed the trailer home for the first time with ALL of the changes in place. My RPM are down nearly 500 RPM at 60mph. The same hills where the truck used to struggle somewhat are now conquered with ease. One hill in particular is VERY steep and about a quarter mile long. The truck used to stay in first gear and work VERY hard to get up the thing. It now shifts into second gear after about 200 feet and just walks right up the hill at about one quarter throttle, running at about 35mph and about 3200 RPM. I used to have to mash down on the gas peddle and literally scream the engine just to get up this hill.
I still don't know if the truck will run as cool as I want it to in mid summer at 900 plus, but I know I have solved the power issues. I would highly recommend that anybody needing a little boost in power or mileage or both, in their tow vehicle take a good hard look at what I've done. For the price, it's a no brainer as far as I'm concerned. By the way, on the trip to Indy the air temp was around 800 or so and the truck temp was never over 1750 even going up some of the longer grades or running headlong into a pretty strong head wind as we did on the way home.
I hope this helps some of you guys out, if you're having some of these issues with an older truck, or a new one for that matter. Several people on the websites where I got some of the info that I used to make the decision to do this were more than skeptical about any of these changes doing much at all to make a difference. Well I am here to say Bull Sh** to all the nay sayers. This really did work on my truck.
My next project is to get the rusted areas cut out and new panels put in and paint the truck to match the trailer. That one will take me a while because of $$$$. But I'm a patient man.