'71 C20 5.3 Conversion
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Teching In
Joined: Aug 2013
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'71 C20 5.3 Conversion Guys, I am planning a build for my 'ol girl, looking to make abit of a sleeper. My goals are
-Descent mileage Ideally around 20 highway
-Reliability
-Powah!
In place I have long headers through 2 1/4" duals to glass packs, 350, Muncie 4 speed, Dana 60 3.73
I am thinking keep the stock trans, bolt in a 5.3. I may turbo it one day and am expecting to be around 500hp, that being said as I add parts I plan on making sure they will support that goal Ie. fuel pump and clutch. Of course budget is a factor so I am trying to do this reasonably. I will plumb into my current exhaust system. As I understand it I will need to track down a flywheel as my SBC one will not bolt up. As you can probably tell I need to learn ALOT about all of this. I am also thinking about putting a cam in it, not sure if or how that will hurt my economy and how comparable it would be if I decide to shove air down its throat. Oh and this is my first post here
-Descent mileage Ideally around 20 highway
-Reliability
-Powah!
In place I have long headers through 2 1/4" duals to glass packs, 350, Muncie 4 speed, Dana 60 3.73
I am thinking keep the stock trans, bolt in a 5.3. I may turbo it one day and am expecting to be around 500hp, that being said as I add parts I plan on making sure they will support that goal Ie. fuel pump and clutch. Of course budget is a factor so I am trying to do this reasonably. I will plumb into my current exhaust system. As I understand it I will need to track down a flywheel as my SBC one will not bolt up. As you can probably tell I need to learn ALOT about all of this. I am also thinking about putting a cam in it, not sure if or how that will hurt my economy and how comparable it would be if I decide to shove air down its throat. Oh and this is my first post here
Last edited by Fly By Night; Aug 10, 2013 at 06:26 PM.
Nice, I'm doing a similar swap. I just got a LQ4 and a 4l80e that I'm swapping into my '70 C10.
I suggest checking out 67-72chevytrucks.com. There is a whole section dedicated to LS swaps with more knowledge that you will ever need. It is definitely possible to keep your stock transmission! Sorry, don't know the details though.
Also, check out LS1Nova71's build in this section. He is very knowledgeable when it comes to these trucks.
I suggest checking out 67-72chevytrucks.com. There is a whole section dedicated to LS swaps with more knowledge that you will ever need. It is definitely possible to keep your stock transmission! Sorry, don't know the details though.
Also, check out LS1Nova71's build in this section. He is very knowledgeable when it comes to these trucks.
Fuel injection will only help gas mileage so much. An extra gear or two, will definately help keep your rpm's down on the highway and give better gas mileage. If you can afford it. Your still better off with your 4 speed than the other guys with t350/400.
Thread Starter
Teching In
Joined: Aug 2013
Posts: 16
Likes: 0
Nice, I'm doing a similar swap. I just got a LQ4 and a 4l80e that I'm swapping into my '70 C10.
I suggest checking out 67-72chevytrucks.com. There is a whole section dedicated to LS swaps with more knowledge that you will ever need. It is definitely possible to keep your stock transmission! Sorry, don't know the details though.
Also, check out LS1Nova71's build in this section. He is very knowledgeable when it comes to these trucks.
I suggest checking out 67-72chevytrucks.com. There is a whole section dedicated to LS swaps with more knowledge that you will ever need. It is definitely possible to keep your stock transmission! Sorry, don't know the details though.
Also, check out LS1Nova71's build in this section. He is very knowledgeable when it comes to these trucks.
I thought about swapping transmissions to get O/D but I am going to wait for now, the truck doesn't see alot of highway miles at this point.
Thread Starter
Teching In
Joined: Aug 2013
Posts: 16
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At this point I am thinking Walbro 255 on the frame rail along with a Corvette fuel filter/pressure regulator.
What brand/style of clutches do you guys recommend?
I would like to get a clutch that is comfortable for N/A for now, around 300hp and also hold on if I decide to turbo and go to ~500hp, that being said I would also like to be able to do clutch dumps in 3rd gear which is 1.7:1 which may be a lot to ask in a 4,000# truck and not have the clutch be really stiff.
What brand/style of clutches do you guys recommend?
I would like to get a clutch that is comfortable for N/A for now, around 300hp and also hold on if I decide to turbo and go to ~500hp, that being said I would also like to be able to do clutch dumps in 3rd gear which is 1.7:1 which may be a lot to ask in a 4,000# truck and not have the clutch be really stiff.
