Author Topic: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..  (Read 9234 times)

Offline sierra79

  • New Users
  • Posts: 2
1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« on: July 08, 2011, 03:59:40 PM »
hi everyone im new to this site and i just wanted to know what are some basic stuff you have to do and buy for a 1979 sierra grande in order to increase speed and power and performance ohh by the way its a k15 350 4x4. thanks

Offline DustyRusty

  • Junior Member
  • ***
  • Posts: 567
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #1 on: July 08, 2011, 04:56:12 PM »
The only thing I did to mine was add a set of long-tube headers and dual exhausts.  I noticed a slight increase in torque and a very minor increase in mpg.  Do you know what rear-end gear ratio you have?  That may be a consideration depending on other things.

Others that have made more major mods will chime in, I'm sure.

Rusty
1975 K-10 SWB Fleetside - 350/SM465/NP205/D44F 12-boltR, 3.73 gears.  Original owner.
Customized by rust.

Offline 1980c10

  • Senior Member
  • ****
  • Posts: 1205
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #2 on: July 09, 2011, 12:13:55 AM »
I would look for a good deal on a good set of heads if you want to make a big improvement. Other wise in stock form just having it properly everthing properly tuned and adjusted could make you some gains depending on what you are starting with. What are your goal and what is your budget for this truck? Also has anything been done to the engine as of now?

Offline sierra79

  • New Users
  • Posts: 2
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #3 on: July 13, 2011, 01:44:51 PM »
i want this truck for off road my butget right now is $1500 no more than that i will post some pictures later but thanks for your advice and what about the air filters do they make a good improvement.?

Offline Psycho71

  • Registered Users
  • *
  • Posts: 239
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #4 on: July 13, 2011, 10:45:17 PM »
Hmm, for $1500 you could, maybe, do a vortec head swap, get the needed intake, do a cam swap, and a new carb, along with some headers. You might have to hunt and scrape on a few parts to save a little bit. But if you're not in a hurry, it is something to think about. Provided the lower end of the engine is sound.

For the air filter, I use a 14" round x 5" element on mine. Don't fall for the K&N crap. They suck on a vehicle that will be operating in the dirt. I've never actually seen any proof they make any improvement at all, in any environment. But they work as intended, by separating the buyer from their cash.

But I agree, first thing, and cheapest route, would be to make sure everything you have in place at this time is working at it's peak.
« Last Edit: July 13, 2011, 10:47:51 PM by Psycho71 »
There are two tools needed, duct tape and WD40. If it moves and shouldn't, use the duct tape. If it doesn't move and should, use the WD 40.

Offline 1979C20

  • Senior Member
  • ****
  • Posts: 1659
  • Kyle Taulton.
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #5 on: July 14, 2011, 03:25:06 AM »
For $1500 you could probably build a meaty Vortec 383, if you have it machined and build it yourself.
1979 SCLB C20 Q-jet 350 SM465 14b F.F. 4.10 G80
1989 GMC Suburban V2500 TBI350 TH400 4in lift 35's 14b SF

Offline BULLDOG

  • Newbie
  • Posts: 49
« Last Edit: July 14, 2011, 08:13:55 AM by BULLDOG »
Black 1983 K20 and sm 465

Offline mats1985gmc

  • Newbie
  • Posts: 77
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #7 on: July 31, 2011, 12:07:41 AM »
heads,cam,carb headers. If you got 1500 to spend you could do that with used parts. You would just have to do some work yourself. swap you gears for some 411s if your just playing in the mud.

Offline BBCurtiss

  • Newbie
  • Posts: 25
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #8 on: August 16, 2011, 01:25:14 PM »
For starters, you'll want it to breath and well, let the stuff you don't want, out.  Start with an exhaust system with some better flowing mufflers and a set of long tube headers., you'll want to stay away from a baffled style glass pack (something with a swiss cheese looking tube instead of louvers if you want gp's) and chokemaser mufflers. you'll want somewhere around 2.5 inches for dual exhaust. for headers, get some with some decent sized primary tubes, and make sure they're long tube!!! with that, you should be noticing a bit of fuel millage increase, and a bit of power. next you'll want an intake manifold. make sure it suits what you have going, a manifold for 500hp at 6000rpm is going to hurt your power. to match your manifold, you'll want a carb. around 600-650 cfm should be good. and then you can work your way into a cam and have a world of a difference in your motor.
if it ain't leaking, it's empty

Offline bowtieman82

  • Newbie
  • Posts: 58
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #9 on: August 19, 2011, 09:09:11 PM »
if it 4x4x you will want to keep your power down in the low rpm. Run Voo Doo cam 60102LK, a holley intake 300-36 and a demon carb 4282010VE. You will all so need a hotter spark. run msd coil, Ignition Modules 83647 and wires.  you will have to put in a Mr. Gasket HEI Advance Curve Kits 6011 for your dist. it will help. your heads depend on what type you have. im runing factory 72cc heads and i have 10:1. i get 16 mpg with 33's on my truck. you will have set the card up. but once u get it dialed in they run great. and all this you can do in steps and you can do it you self none of it is really hard. the card just watch the movie and get some jets and sec vacum springs for that all u need to buy for the carb. but it will run great and last a long time.

Offline The dream

  • Registered Users
  • *
  • Posts: 147
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #10 on: August 24, 2011, 07:45:28 PM »

My advice is to aim lower from your budget, don't spend all of it in parts because something always comes up that you don't expect.
Never give up.

Offline Irish_Alley

  • Tim
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 13319
  • Family is not an important thing. It's everything.
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #11 on: August 24, 2011, 07:53:20 PM »
do you plan on lifting or mudding with it?
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline bowtieman82

  • Newbie
  • Posts: 58
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #12 on: August 26, 2011, 12:44:26 AM »
if you have 1500 frist fix all the thing wrong with it. them inprove it and start small. do thing in step befor u inprove power, inprove breathing like exhust, air cleaner, intake, carb. run a K&N air cleaner. them work on you ignition system. then do the fuel system. and you can do all this over a year or so when you have the money. just put on what you want. and dont buy something cause somebody say to. go look at what someone eles has with the same truck is running and see what they have. it will help u see what work for what you plan on doing with the truck. just plan it out. and stay with it. i learned the hard way. i bought what other people had, and found out what they had didnt work for my truck, and my needs.  you will need to find out what gears you have the type of tranny you are running. if you are going to lift it or not. all this is what you have to use to buy what you need for you truck, so you buy the right stuff the frist time, and dont have to buy parts over and over.

Offline Irish_Alley

  • Tim
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 13319
  • Family is not an important thing. It's everything.
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #13 on: August 26, 2011, 10:45:57 AM »
one thing i do is make sure when i buy something im not wasting my money like buying a aftermarket intake that will work now but not with future upgrades. Or buying tall gears now to help with takeoff but then changing my cam to work with another set of gears
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline lukieg

  • Registered Users
  • *
  • Posts: 100
Re: 1979 SIERRA GRANDE HOW TO INCREASE POWER AND PERFORMANCE..
« Reply #14 on: September 18, 2011, 07:01:39 AM »
 Toss a set of headers on it... and a decent rv cam... tune it... make sure the carb is in proper working order.. dont waste cash on intakes and carbs... the stock one works great for torque... remember general motors didnt get to be the best by having designers that are retarded! Something to think about