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Phlebmaster's 1972 C20 Evolution***56k- NO WAY!

Hello,

My name is Aaron, I am new to this forum, I have a 1972 Chevy C20 I picked up after selling my Datsun 240z project. I have been updating my C20 project thread on the Datsun enthusiast sites (you can google my username if you are curious) and thought I should post this up here. Be aware that this post will be long and full of pics to get you up to speed on my project. Thanks for your time. Aaron

Please forgive the multiple posts.

Here we go........11/17/09

Well, I did what I said and picked up an older Chevy truck after I sold my 240z. I just got it home this morning.

I now have a 1972 Chevy C20 3/4 ton Camper Special. :) I paid $600.00 for this beast. She needs a few things but there is very little in the way of rust and I just happen to have an extra 350 sbc to throw in once it is re done. :D

I have not had time to look every little thing over...but the truck has a 350 and I am not sure if it has the TH350 or TH400 since it is a 3/4 ton. But it runs good, sounds good, and shifts nice.

Ok...here are the pics.

http://i34.tinypic.com/2053u3l.jpg

http://i33.tinypic.com/16c7swm.jpg

http://i38.tinypic.com/16iv5s6.jpg

http://i37.tinypic.com/21e7qyf.jpg

http://i35.tinypic.com/25fnp.jpg

I can tow stuff now.

Not the prettiest example of a classic Chevy truck...but very functional and workable.

I picked this up! Edelbrock Performer intake.

http://i38.tinypic.com/2ynnu34.jpg

Here is how the engine looks now....kinda ugly. I will take pictures of the "after" I make my changes so you have a comparison.

Before...
http://i50.tinypic.com/29ap99h.jpg

This is what is going on the 350.

http://i48.tinypic.com/c4029.jpg

http://i46.tinypic.com/f44eig.jpg

This is a Comp Cams 270H with a 112 LSA and 4/7 swap. I can't wait to get this in.
http://i46.tinypic.com/fxfnf8.jpg

http://i48.tinypic.com/1sjfas.jpg

http://i47.tinypic.com/vb14l.jpg

Well, after much research and discussion with those who know about what I plan on doing with my engine I have decided to do this one step at a time rather than all at once.

Tonight I put my new intake and Holley 750 on. :D I will install my cam once I get heavier springs. I can tell you this about the stock crap that was on my truck...the intake had a bunch of loose bolts and all of the fittings were not tight either. It is a wonder it even ran! I fixed that though.

I will not be able to test this new stuff out until I get a new water fitting that runs from the intake to the heater core.

Here are the obligatory pics of the swap!

So it begins,,,,
http://i45.tinypic.com/30wov84.jpg

http://i46.tinypic.com/2i78cwz.jpg

http://i50.tinypic.com/330xxt1.jpg

Now that feels better already! Damn that thing is heavy!!
http://i47.tinypic.com/2ai29sj.jpg

http://i49.tinypic.com/15f0m7o.jpg

http://i47.tinypic.com/rviro8.jpg

All finished for tonight...I can't wait to start her up tomorrow!
http://i46.tinypic.com/29fpbbm.jpg

http://i48.tinypic.com/2s1szo9.jpg

I started to tear apart my motor tonight so I can put my new heads on and make sure my cylinder walls are ok.

http://i46.tinypic.com/2wechvp.jpg

http://i49.tinypic.com/zu0bhv.jpg

http://i46.tinypic.com/vqnlvl.jpg

http://i47.tinypic.com/bafc3.jpg

http://i49.tinypic.com/rhipu1.jpg

http://i46.tinypic.com/2cyr52v.jpg

http://i45.tinypic.com/2luuhaf.jpg

I have dished pistons so I can get away with the small chamber heads I am going to use.

http://i47.tinypic.com/1gmbuw.jpg

A little paint for show....
http://i49.tinypic.com/6r6iwz.jpg

The 624 heads that were on my truck are the 1.72 valve!! I am glad to not have to use them any more. Now I have a set of 1.84 1.50 valve 58cc heads. You can compare the old head on top with the 58cc head below.

http://i48.tinypic.com/2mnqjkn.jpg

Progress tonight!

I put on the new heads and got them bolted down. I followed the correct torque sequence and procedure for getting them done right.

Feels good to make some progress! Now I just need the friggin carb that works. lol

http://i47.tinypic.com/2ly3ek8.jpg

http://i48.tinypic.com/21jt4hw.jpg

http://i46.tinypic.com/eaqt7a.jpg

http://i49.tinypic.com/15cf3uu.jpg

I made more progress tonight....
http://i45.tinypic.com/2zock95.jpg

I got me a new Edelbrock 1404 500 CFM carb tonight that is actually NEW!! Thanks to Blackice280z and kamakazi620. :) I also have a good Q-jet coming tomorrow....so I will have two q-jets (one good & one worn out) and one new 1404 carb at my disposal. I am very happy about that.

http://i47.tinypic.com/68au8h.jpg

http://i45.tinypic.com/oaaicp.jpg

Funny thing...it says Weber on it! lol

http://i45.tinypic.com/xeg2hg.jpg

http://i46.tinypic.com/2rp48lw.jpg

I got her running tonight!! YAY! :D I will have a video tomorrow including before and after shots.

http://i50.tinypic.com/347zgv4.jpg

http://i47.tinypic.com/vo65uw.jpg

Update 12/26/09

Here is the video. :)

enjoy!

YouTube- 350 sbc head swap -081 heads 1.84/1.50...

I picked up my headers tonight. Maybe a swap this weekend?? I don't have the flange/reducer portion that goes from the headers to the main exhausts, or the heavy gasket, or the locking header bolt/nuts. :( But those are not that expensive.

http://i48.tinypic.com/24q3kuo.jpg

http://i49.tinypic.com/8x7erb.jpg

http://i48.tinypic.com/2r7ub5u.jpg

I got bored this weekend so I decided to swap in my cam. :D The cam is a Comp Cams Magnum series 270H 112LSA with the 4/7 swap. This was actually easier than I thought it would be. I have no coil bind or issues with my rocker travel. The springs are new springs so will work with this cam until I can get my vortecs.

Here are the pics.

This picture was a big help!
http://i47.tinypic.com/2j17byp.jpg

I was happy to see this under the timing cover.
http://i49.tinypic.com/2lrl2t.jpg

Here is the old lifter...it looks like someone has replaced them along with the cam because the cam looks to be in great shape and these are definitely Comp Cams lifters.
http://i46.tinypic.com/112hh00.jpg

http://i46.tinypic.com/21ad0me.jpg

Here is the new cam all lubed up and ready to slip in.
http://i47.tinypic.com/2wf25vm.jpg

http://i47.tinypic.com/n350f5.jpg

Here is the old timing set, I am looking for a gear drive set up.
http://i46.tinypic.com/10p99hd.jpg

It was late so I was not going to rev the motor at 2000 rpm for 20 minutes...I will do this later today. Video to follow of course!

update 1/12/10

Here is the promised video. :)

YouTube- 350 with Comp Cams Magnum 270H 112 LSA...

This was my first time swaping a sbc cam. I left the 081 heads stock on my 350, but put new extreme push rods, 270h cam, and lifters. So, you can run a .470 lift cam on stock heads,(WOULDN'T RECOMMEND IT...but I did it). I spent many weeks looking for that answer ans now I have the experience for my self. I also could not find a good sound clip of this special grind cam online- so now there is one....enjoy!

Just so you know, I am running 305 (081) heads on my 350 and I am very happy with the results. I read way too many posts on way too many forums saying yes...no...yes..no....and I was like what the hell?? So I did this for my own knowledge and experience.

So, let's sum this up:

First Myth: you can't run 305 heads on a 350......

Can you run 305 heads on your 350? = YES! And you can get a decent flow with the right heads, stay away from the swirl port heads. Use the 081 non-swirl type. I would have prefered to used some 350 after market heads or maybe even vortecs....but I had these heads so I used them. 350 heads will out flow and out perform any 305 heads anyday, but if that is what you got...them use them.

Be carefull about your compression ratio, I have stock 12.5cc- 4 valve relief dished pistons and with 58cc 305 heads I am at about 9.74:1 to 10.00:1 compression so I will be running premium fuel. Flat top pistons will make your compression ratio bump beyond that and you may be buying expensive gas to drive your rig....so look out for that.

Next myth: max lift for stock heads is .450 or ?????.....

Can you run a .470 lift cam on stock heads?? = YES! but you must make sure you look for coil binding and clearance between the spring retainer and valve guide before you run the motor. DO NOT REV your motor the moon!! Stock springs especially worn ones will not handle the ramping at all, and you will have valve float. I recommend using the recommended set-up by your cam manufacturer.

I went through many weeks of looking for a simple answer online and never found a strait answer. I hope this information helps the next person who reads this post.