How not to built an L67

[Immortality]

A quick video lesson on how to NOT build and L67 with a very predictable outcome.

And the result....

 

[shane_3800]

I commented on one of his videos about using late model powder rods. He replied with "I don't trust powder rods"????? What does he think LS engines use?

 

[shane_3800]

Are the valves bent? Seriously.... I'm about 99.9% sure these are interference engines.

 

[Immortality]

There is nothing wrong the strength of the L67 rotating assembly, others have gone well over 400rwhp with them.

We warned him about the timing chain but he ignored it and so this morning I totally pissed myself laughing when the video popped up.

Yes, it'll have bent valves no doubt, they recon they were only cruising so hopefully only 1 or 2 bent valves. He said it just stopped dead so it definitely something hit something. But then he just spends ages cranking it over on the starter regardless. He definitely isn't the most clever tool in the shed.

 

[losh1971]

Interesting vid, what sort of KW can the stock chain handle? I'm second guessing my choice of single row, but stronger than factory if I eventually go boost.

 

[Immortality]

Nothing to do with HP. All to do with cam and the springs. Double row chains are recommended for any valve springs with more than 105lbs on the seat (stock springs are 60lbs). The cam in that L67 requires a minimum 130lbs on the seat but likes more if you like to rev the motor.

That stock chain was a recipe for disaster. It was also a new chain on used high mileage sprockets. That cam also uses a reduced base circle diameter lobe on the intake and a lot more lift than a stock head will take.

 

[losh1971]

Hmmm not sure what lb springs I have, they are heavier than stock Buick ones. I believe they are Crow, one stiffer than stock.
That bloke should have known better, since he obviously owns a garage

 

[losh1971]

Nothing to do with HP. All to do with cam and the springs. Double row chains are recommended for any valve springs with more than 105lbs on the seat (stock springs are 60lbs).

Do you happen to know what the one step up in Crow on the Buick is Mort? I had an idea they were 90lb but looking at Mace site I see they sell 115lb.
I do have an upgraded single row not stock GM.

 

[Immortality]

You would have to check the crow catalogue, Mace only stock a small selection to suit their cams.

Ask the guy who did the heads what he fitted, maybe it's on the invoice if he supplied new parts.

 

[losh1971]

Yeah I will have to check the invoice and see if he has a part number on them.