Broken Timing Gear Bolt in Cam? Need a new Cam? Recommendations for a lifted DD?

L31MaxExpress said:

FWIW, you are not alone. I found 2 broken head bolts and a broken head bolt washer in an engine I built a while back while putting a marine manifold on it. What a freaking nightmare an intake swap ended up becoming. However, I guess I am lucky I discovered it before the head warped, the head gasket went, and I had a far more $$$$ failure on a 383 with low mileage. I torqued to 70 ft/lbs per the instructions and later found out that the washers could potentially act like a bearing causing the bolts to be over torqued resulting in them failing. It would not have been such a PITA had I not decided to do the intake manifold at my mom's house that I am helping her remodel more than 100 miles from my shop. Immediately after I started the project we also became sick with Covid and I was down for more than a week. I elected to remove the heads in chassis which also turned out to be a real bear considering it is in my Express van and everything space wise is limited when it comes to the cylinder heads. Finally being in the country everything takes 2 additional days to make it that extra 100 miles. My shop is 20 minutes drive from Summit in Arlington, TX and I have the Oreilly, the Autozone and the Advance mega hub stores less than 1 mile away all at the same intersection. I also have about 6 junkyards that I could almost throw a rock at there. I of all people absolutely do understand the headache working on these older vehicles can become.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Click to expand...

boy&hisdogs said:

Sheesh that sounds fun! I think the lesson I learned today is that new bolts are worth every penny. There's an Ace hardware right down the street that had the bolts for 75 cents each. From now on I'm not re-using important fasteners on a high mileage engine anymore.

Click to expand...

L31MaxExpress said:

FWIW, you are not alone. I found 2 broken head bolts and a broken head bolt washer in an engine I built a while back while putting a marine manifold on it. What a freaking nightmare an intake swap ended up becoming. However, I guess I am lucky I discovered it before the head warped, the head gasket went, and I had a far more $$$$ failure on a 383 with low mileage. I torqued to 70 ft/lbs per the instructions and later found out that the washers could potentially act like a bearing causing the bolts to be over torqued resulting in them failing. It would not have been such a PITA had I not decided to do the intake manifold at my mom's house that I am helping her remodel more than 100 miles from my shop. Immediately after I started the project we also became sick with Covid and I was down for more than a week. I elected to remove the heads in chassis which also turned out to be a real bear considering it is in my Express van and everything space wise is limited when it comes to the cylinder heads. Finally being in the country everything takes 2 additional days to make it that extra 100 miles. My shop is 20 minutes drive from Summit in Arlington, TX and I have the Oreilly, the Autozone and the Advance mega hub stores less than 1 mile away all at the same intersection. I also have about 6 junkyards that I could almost throw a rock at there. I of all people absolutely do understand the headache working on these older vehicles can become.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

Click to expand...

HotWheelsBurban said:

Does look pretty cozy in there! I did a tune up and thermostat+ housing on a G20 van with a TBI 350, several years ago. It was a company vehicle, our regional HQ was in Austin and they couldn't find a garage down here that was trustworthy....
So I volunteered to fix it. That job wasn't too bad, but I wouldn't want to do much more than that to it w/o a tilt front clip or something....and I was 25 years younger too! Very interesting, to see a Chevy distributor from the opposite direction you usually do though.

Click to expand...

L31MaxExpress said:

Gives great access on the oil pressure sending unit as well as that pesky 8.1L crank sensor that is nearly IMPOSSIBLE to remove on a truck.

The G20s are not bad at all. I have done numerous head swaps and repair jobs on them over the years. This one is a SOB compared to a G-van. The engine opening is completely under the dash where the G-van half the engine sits exposed in the floor.

Click to expand...

L31MaxExpress said:

GM 94666492, just over $100 and it is a GM steel roller cam, ever so slightly larger than the L31 cam and shorter duration than a LT1 cam and fits with stock vortec springs. It runs extremely well even in a TBI on the stock tuning. I am just finishing a L31 build with this camshaft and have used it in the past on a couple of other EFI small blocks. The cam is a Vortec 350 marine cam, meant to idle slow and smooth, have good torque and make about 300 hp with stock iron vortec heads. BluePrint and GM are getting 383s through smog requirements on the stock Vortec tuning, your PCM will care less about this tiny little bump in camshaft.

Click to expand...

HotWheelsBurban said:

How about belts, hoses and water pump on a G20? That's what I was not looking forward to doing....
When the company closed, we had the option to get a van really cheap, like under a grand. They'd all been poorly maintained and had the **** run out of them though, so we declined the offer. If I could've been sure that I got a decent one, I would have, because I used the one we had for a few swap meets, and I could put so much more stuff in it than in the Burb....
I have wondered how easy the Express vans were to service (since that was supposed to be improved on them, over the older models). Guess you've answered me there!

Click to expand...

boy&hisdogs said:

Is that 492 cam a direct swap? No other modifications or changes? If so that might be the way to go.

I bet a shop would charge more to repair my existing cam, and a junkyard cam would run nearly half of that already, not even counting the time it takes to find and pull it.

Click to expand...

L31MaxExpress said:

GM made huge improvements around 1992 on the vans. When they did away with all the goofy brace brackets and that dumb stamped steel accessory bracket or the older individual brackets for everything. When I had a small block in my 1983 I had converted it to an accessory setup from a 1992 G20 van. The 1992 setup was very nice for service sakes. GMs 2-piece fan shrouds also helped things noticeably. On the never vans, belts, hoses, and accessories are not much more difficult than they would be on your suburban. On the Express vans the coolant reservoir and the air cleaner assembly removes with a few 10mm bolts. Once those are out of the way, its really no more difficult to change an alternator than it is on your suburban. A water pump on a 92+ van requires only removing the fan clutch and the water pump. The one hose I will always hate is the bypass hose. The 96+ vans do have two heater hoses and the water control valve in a really messed up place. That being said I replaced both of those hoses with a 90* silicone hose the appropriate length and used a new GM 4 port diverter when I did. With any luck those silicone hoses will last the life of the van. The OE rubber ones still seemed good at 23 years age and the diverter never had leaked, but I felt they were on borrowed time when I put the 383 in.

Click to expand...