New Chevy C20 owner

**jwindbigler** · 05-15-2011, 11:33 AM

I just got my first C20. Its an 86, and I would like to clean up the engine a little bit as well as get some more low end torque out of the 454. I have no idea where to start. I know that its got a 3 speed auto in it now, with 3.23 rear gears. Didnt know if I should start with putting in a different trans. Putting in a different intake manifold, or headers. Keep in mind this is a beater truck, and I want to be CHEAP. Its not a daily driver. Its sole intention is to pull cars on a trailer and pull them to my residence and fix them. So any direction would help a lot. Thanks guys.

Justin

**Firebirdjones** · 05-15-2011, 05:55 PM

I've had a 79 454 1 ton for years that I use to tow with. Great durable trucks.

What I did with mine initially for more towing power is a set of headers, and a free flowing dual exhaust setup. Then a simple performer intake with a matching performer camshaft,,,all in an effort to make power right off idle. I found alot in just tuning. Tweaking the quadrajet with internal mods (too lengthy to get into here) and a good distributor curve with about 18 initial and 38 total. With the factory 400 turbo and 3.73 gears along with these mods, it would tow my 28 foot enclosed all day long at 10,000 lbs loaded.

If you have a factory 454 truck, then a 400 turbo trans should be what is behind it. I'd leave it be if you plan alot of towing. If you really want an overdrive then a 4L80E would be the only option I would consider, and thats a pricey swap. A gear vendor unit would be another way to go, but again very pricey. Otherwise there isn't another trans out there I'd trust to be towing what these trucks are capable of,,,which is why GM never put them in these trucks to begin with.
For just a tow rig that isn't driven daily,,,I found it to be a waste of money to install an overdrive.
I've recently installed a GM crate 502 in mine now with even more grunt.

Not much else for modding you can do that is all that cheap,,but the only tow rig that is any better is a turbo diesel,,,but they are a hell of alot more expensive. So you can look at it from that point of view or cost perspective if it makes ya feel better. That's what I did. It was cheaper to install a 502 rather than buy a new turbo diesel.

**REVNORR82** · 05-15-2011, 06:00 PM

Cam intake headers gears start the stump pulling!!!

Sent from my DROIDX using Tapatalk

**jwindbigler** · 05-15-2011, 06:05 PM

Mine is a 3 speed auto. That's what the sticker says in the glovebox. Is that still a turbo 400? Because I thought those were 4 speeds.

I was thinking cheap headers, the intake and that's really about it. What intake did you go with? What headers did you go with?

Thanks

Justin

**Firebirdjones** · 05-15-2011, 06:57 PM

Yes it should be a 400 turbo if that's an original big block truck. The 400 is a 3 speed auto. If you are looking at the glove box sticker with the codes it should probably say M40 next to that 3 speed auto description. That's RPO lingo for a 400 turbo.

I am using the Edelbrock Performer intake on mine. Simply because it makes power from idle to 5500 which is what you want for a vehicle like this. It's been many years since I bought the headers but I believe I have a cheap set of Hedmans on there with 1 3/4 tube. Worked fine for a low rpm 454 but I feel they are a bit too small for the 502.

**jwindbigler** · 05-16-2011, 04:03 AM

I was looking at the Edelbrock performer intake. Did you do anything with the carb at all?

**1fastcamarosss11** · 05-16-2011, 05:30 AM

if you ever need a 400 trans let me know.

**jwindbigler** · 05-16-2011, 05:32 AM

Do you have a munice 4 speed?

**1fastcamarosss11** · 05-16-2011, 05:44 AM

no i needed a 400 trans and the guy i got it from had two so i got a good deal on two just used one.
i have an 79 c 30 i plow with. it has the utility bed on the back with the 6 boxes. pretty good shape for a city truck from jersey. about 70k on it. but was used for plowing.

**jwindbigler** · 05-16-2011, 05:47 AM

How much you looking to get out of the trans? Does it include a transfer case?

**1fastcamarosss11** · 05-16-2011, 05:51 AM

i only want 250 plus shipping i got it from a guy who buy trucks out by you. brings them back here and strips then down. you should see the trucks he breaks down almost made me cry. he said he get 1500- 2000 for just the beds on these trucks. trans has 55k on it.

**jwindbigler** · 05-16-2011, 05:56 AM

I'll keep it in mind. I don't need it as it would just sit in the garage till I needed it

**1fastcamarosss11** · 05-16-2011, 06:09 AM

Originally Posted by jwindbigler

I'll keep it in mind. I don't need it as it would just sit in the garage till I needed it

took me 2 months to find a usable one. just keep that in mind.

**jwindbigler** · 05-16-2011, 06:12 AM

Will do. My truck only has 92k on it, and I don't think that it's been put under a lot of stress as it doesn't even have a ball hitch on it now lol. If I had the cash I probably would, but I simply don't right now. But then again who does?

**Firebirdjones** · 05-16-2011, 07:42 AM

Originally Posted by jwindbigler

I was looking at the Edelbrock performer intake. Did you do anything with the carb at all?

I kept the stock quadrajet and then modified it. Smaller brass float so the float bowl has more fuel capacity along with a larger .135" needle and seat to fill the bowl faster. (stock is around .070" or so)
All in an effort to keep from sucking the float bowl dry, a common problem with quadrajets and their small float bowls.
Modified accelerator pump for more shot, I also changed around the front metering rods and jets until I was happy with the AFR, and changed to a lighter power piston spring to delay the opening rate until 8 inches of vacuum as well as drill through the top air horn with a set screw to make that adjustable. I also drilled the IFR to .034 and I've modified the secondaries slightly, as well as rear metering rods. The 454 liked an .040 rear rod setup with a "D" hanger, I now have .030 rods in there with a "B" hanger to make the 502 happy. Then adjusted the secondary door spring tension. I also epoxy all the well plugs, they are notorious for leaking. There are some other tidbits but that's pretty much the extent of it.

Excellent carbs once you get used to them. The hickups with them are that jets and metering rods aren't necessarily sold in a kit and what is available is all piece meal (usually through Edelbrock or through GM), and not found locally unless you have a really good speed shop in town. You also can't buy gaskets seperately so I end up buying an entire carb kit just to rob the top air horn gasket out of it. Because you'll find yourself removing that airhorn many many times to dial the carb in properly. Eventually the gasket has to be replaced.

You more than likely have a computer controlled quadrajet on that 86 of yours. You are going to be limited to what you can do with it.