73 C20 Performance Engine Build

[BBM3]

Looks great!

What are you doing for fuel? Re-using your TBI?

I'm following along with great interest.

[LTZ C20]

Thanks. Yes I'm re-sign the TBI set up. It worked great before, no reason to stop using it.

[BBM3]

That's a solid plan.
I would love to have fuel injection. My carbureted truck runs noticeably different (in a bad way) when i drive from home at 8000' to town at 6000' ASL.

[LTZ C20]

Thanks. Yea it was great going from carb to FI. I really like that I can just go out and fire it up and walk away, let it warm up or I can eventually hook it up with my alarm and have remote start.

[BBM3]

What type of sensors are you using? O2, MAF?

[LTZ C20]

Standard TBI system sensors, MAP, TPS, IAC, only I have a modified system so I have a 4 wire heated O2 and no EST distributor, so no knock sensor.

[BBM3]

You do have a knock sensor....
Your ear. 

[LTZ C20]

Well yea your right, but it's usually plugged up with loud country music. Lol

[LTZ C20]

On a side note here, I'm considering adding an Air Filter Service gauge. Usually they are mounted on the engine side of an air filter box, but these older systems are directly on top so that idea can be a little challenging I think, to mount it properly it would be in the direct flow of air into the throttle body which I think will present inaccurate readings.

This is not the exact unit I'm considering but most GM ones are about the same.

Any ideas here guys? Theories about how and where to mount it? Directly in the air box or remotely and supplied with a vacuum hose?

[LTZ C20]

Got more goodies in this morning, now major assembly can begin again. Presents from Santa include head gaskets, intake gaskets, cam lock plate, pushrod measuring tool and true double roller timing set. Tonight will be a good nite for progress.

[BBM3]

My diesel pusher motorhome had one of those pulling vacuum after the air filter.
The way to get a reading was to press the reset button on the top while the engine was idling. As soon as I shut the engine off it indicated a clogged filter and always remained that way even when the engine was started again until I pressed the reset button.
I choose to spend a couple more seconds to pull and visually inspect the filter element.

An inexpensive vacuum gauge with a tap after the air filter would accomplish the same with greater accuracy.

Looking forward to more pictures of your engine build.

[enaberif]

On a side note here, I'm considering adding an Air Filter Service gauge. Usually they are mounted on the engine side of an air filter box, but these older systems are directly on top so that idea can be a little challenging I think, to mount it properly it would be in the direct flow of air into the throttle body which I think will present inaccurate readings.

This is not the exact unit I'm considering but most GM ones are about the same.

Any ideas here guys? Theories about how and where to mount it? Directly in the air box or remotely and supplied with a vacuum hose?

My understanding of these is they measure the amount of air being pulled between the airbox filter and the throttle body.

The dirtier the air filter the harder it has to suck which causes this to show you a "Change" but if the filter is new it shows "Good".

If you have a airfilter box and a tube between your filter and throttle body insert it in there.

[LTZ C20]

BBM3, yea I was just curious of whether or not it would be worth it. Most GM trucks after 2000 all have them and curtain ones before 2000. I'm in the habit of once a week I pop the hood and just take a quick peek, make sure everything looks good. Then usually once a month I do a thorough underhood inspection. I would be checking the filter gauge at the weekly checks and the filter itself monthly.

Enaberif, I have the stock air cleaner so to mount it like that I would have to hook it up so that it sourced air from the spacer between the throttle body and air cleaner housing. Not a problem, just wasn't sure what the proper location would be.

[LTZ C20]

More pics. Got the timing set installed and aligned. Luckily for me, the cam has the advance built into it, there for I was told by Comp that I don't need to degree it. Less work for me! Tho I was looking forward to learning how to degree a cam. I've seen that it's really not hard to do. Anyway, the timing set was set to zero as instructed and properly bolted down. I put red arrows at the timing marks for ease of sight.



Check out the adjustability on that crank gear! 9 positions! That is a Summit Racing true double roller timing set, was about 35 dollars I think, steel cam gear, billet steel crank gear and suprising actually had installation instructions labeled by Trick Flow. So, it appears this set is made by Trick Flow for Summit Racing. Very good product for the price, half the money when compared to a similar set from Comp and is actually twice as adjustable if needed.



The cover was installed and torqued down to a heavy 7 ft lbs. Now, I'm not to sure on this part, the edges all seem to be sealed except for around the dowel pin areas. It just doesn't seem right, see what I mean.

Looks ok here,


Doesn't look right here,


Also the oil pump bolt stripped out the first 2 threads in the block.... I swear I'm cursed by bolts.... going to get between a 1/4 in and 1/2 in longer bolt to grab the threads. I've got mixed theories on what the torque spec is for this bolt. I've seen 12-15, 35 & 65 ft lbs. I would love a proper and correct answer to this. I'm thinking 65 is way to much, possibly why the threads stripped out.

Here's a shot with the heads and intake on. Intake is just resting, heads have their bolts but are loosely fitted, will be torqued tomorrow night, those ARP bolts I know for FACT will tighten and torque properly the first time!



Trial and error friends! Trial and error... That's how we learn, after all this is only my second full engine build and I didn't even put the bottom end together haha.

[enaberif]

That timing cover flange is horribly warped. I'd be taking it off and putting it on a flat surface and doing my best to flattent that sucker out.

Also before you get to carried away... Make sure you rotate the engine so that the top dot is at 12 and bottom is at 6. The way you have it now is that it is on the #6 firing order and by rotating it puts it on the #1 firing order.