Sanity check on parts order.

Erik the Awful

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The stamped steel rockers suck. Good roller 1.6s are worth 10-15 hp, sometimes more if the cam is small to start with.
Most of that gain is in moving to 1.6s, which are available in stamped rockers. I do agree that the factory stamped rockers are weak-sauce, measuring 1.48:1, flexing to 1.45:1, but there are aftermarket self-aligning stamped 1.6 rockers available for about $100, which is less than half of those Proforms. Also, the engine's going in a Suburban, so I don't think it's going to see a lot of 6000+ rpm pulls. If the OP wants rockers, fine, but it's $100 that doesn't need to be spent. Yes, I put rollers in my engine, but if I were building it over again I wouldn't.
 

L31MaxExpress

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Most of that gain is in moving to 1.6s, which are available in stamped rockers. I do agree that the factory stamped rockers are weak-sauce, measuring 1.48:1, flexing to 1.45:1, but there are aftermarket self-aligning stamped 1.6 rockers available for about $100, which is less than half of those Proforms. Also, the engine's going in a Suburban, so I don't think it's going to see a lot of 6000+ rpm pulls. If the OP wants rockers, fine, but it's $100 that doesn't need to be spent. Yes, I put rollers in my engine, but if I were building it over again I wouldn't.
Most of the power gained is friction reduction. Its why GM added roller fulcrum rockers to the later 4.3s and LS engines. The pivot balls on stock rockers are high friction, they wear easily and create excess heat. I put 1.6s on a TBI 350 and gained power everywhere, not just high rpm. It gained 10 ft/lbs at low rpm and close to 15 hp @ 5,000 rpm where it shifted at WOT. I put them on the 5.7L vortec with the stock cam and it too gained power everywhere. My 383 had 1.7s on it although I recently swapped to 1.5s on the exhaust to reduce the 10° duration split for testing purposes. The ratio increase alone is good for top-end power, but a roller fulcrum adds power everywhere.
 

Comp112

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Update, I got all the parts in and the truck back together.

To put it short, crank no start. Has good fuel pressure, has spark, spark looks a bit weak. I am going to swap in one of the old distributors I have and see if that might be the problem. Maybe the ignition control module?

EDIT: I double checked the distributor, its set properly, swapped out the ICM just in case, same as before. Its eventually backfiring up the intake, but not really even trying to start.
 
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BeXtreme

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Update, I got all the parts in and the truck back together.

To put it short, crank no start. Has good fuel pressure, has spark, spark looks a bit weak. I am going to swap in one of the old distributors I have and see if that might be the problem. Maybe the ignition control module?

EDIT: I double checked the distributor, its set properly, swapped out the ICM just in case, same as before. Its eventually backfiring up the intake, but not really even trying to start.

sounds like its 180 deg out.
 

BeXtreme

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Thats what I thought at first, redid it twice just in case.
Wouldn't be the first time someone put one in 180 deg out twice in a row. Not trying to be a dick... just that I've seen it done more than once.

How did you confirm TDC on the compression stroke? If it was by using the "finger over the #1 spark plug trick", I would recommend you pull the valve cover and actually make sure you have it on the correct spot.

Another possible cause I've seen multiple times is incorrect firing order. Check your plug wires and firing order...
 

JeremyNH

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Not if you're getting spark. The PCM triggers the ICM to fire the coil based on reluctor lobe position over the crank sensor. Bad sensor would mean no spark. The tach on the dash counts the pulse rate to the ICM so if you are seeing about 300-400 rpm on the dash during cranking it confirms you don't have a crank sensor issue. One thing about the distributor is that dot:dot is #6 TDC compression not #1. Probably you know that but almost half the posts on the web have it backwards so just want to throw it out.
 

Schurkey

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Confession:

I put the distributor in backwards on my own K1500 after replacing intake gaskets. I put the engine on TDC, took pictures of the rotor position...and then three weeks after pulling it apart, I put it back together with the rotor pointing at #1.

Wouldn't start.

Another week later, I'm going through my photos and noticed that the thing came apart with the rotor pointing to #6. Re-stabbed the distributor, and it runs great.

I'm telling myself that if I wasn't called away on family business, if I'd put it together the day after taking it apart, that mistake would never have happened. If I'd even had enough sense to refresh my memory before putting the distributor in, I'd have been fine. The older I get, the easier it is to distract me.

LOOK! A squirrel!
 

Comp112

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Not if you're getting spark. The PCM triggers the ICM to fire the coil based on reluctor lobe position over the crank sensor. Bad sensor would mean no spark. The tach on the dash counts the pulse rate to the ICM so if you are seeing about 300-400 rpm on the dash during cranking it confirms you don't have a crank sensor issue. One thing about the distributor is that dot:dot is #6 TDC compression not #1. Probably you know that but almost half the posts on the web have it backwards so just want to throw it out.
You know I noticed it actually wasn't showing anything on the tachometer when cranking.

Can a bad ground potentially cause this?

EDIT: Double checked, 0 RPM on the tach when cranking. I'll need to double check the spark, see if it is actually producing anything.
 
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