Hey everybody! I've been lurking around for a long time on this site. I've spent hours reading the posts. Thanks so much for all the info! I know I don't have a third gen, but my block/trans is camaro stuffs! WcT5 and 69 camaro 300hp block. So its a camaro at heart, just gave up on his diet!

I'm waiting for a xe268 comp cam for my 86 Chevy c10 It has the 416 heads and a flattop 350 bottom end. I haven't had it apart yet, so I cant tell you all the exact numbers on it. I drive this truck everyday, I am wondering if I should install the cam retarded to help with detonation? I spoke to the original builder of the motor once for about 2 minutes, he asked about the trans and I asked about the pistons, all I had time for. I do plan on takin the heads off so I'll go thicker on the head gaskets.

I do have access to $2 a gal straight Meth hmmm... Just kidding. Though thats not really too far fetched eh? Have to look into what it would take to convert pemanently. Even with the extra fuel goin in it should be cheaper! Especially with the way gas is goin up like crazy again.

 

No do not retard the cam. You do not need to.
The cr will not be excessive with 416's on a 350.
Get some champion RV8C spark plugs and recurve the distributor
or 20 to 24deg at idle and 34 to 36deg max mech advance @ high rpm.
Do not advance or retard the cam.
use 92 octane gas.

if you want actual power using the 416 heads on a 350 then generously port them.
larger 1.94x 1.60 valves help too.

 

Just the guy I was hopin to reply to this this. Good to know. I run 91, best I can get, and it likes about 32-34 right now anyway. I plan to clean the heads up lightly, port match, but next year...ish I'm goin turbo ls1/t56. So I'm not goin too far, just better.

And I wanna thank you specifically for all the time you put into helping other people with there builds. Really makes a difference.

 

Also I use Ac Delco RT42s or 3s, can't remember which ones worked the best.

 

The AC R42T (no S) is the same plug as the RV8C
34 deg is fine.

Porting: if you only do a modest effort job don't expect much more than a modest
gain. The meat and potatoes is found deep in the ports using the long shaft cutters.
use a felpro 1205 gasket as a guide.

 

I don't expect much if anything out of this. I do think my current cam is fairly worn though. The P.O. didn't know how to tune the motor at all, when I got the truck it was running 40*s total timing and 87 octane. Can't believe he didn't hurt it. It was crazy rich too. The s on RT42s was plural. haha! oops

 

A bit too much cam for virgin 416s.

 

Anything less is too small for the compression especially when its cold outside. Like I said I only plan to run this setup for a year or so. Why would I keep this sh*t setup when I can get stupid power for 4-5k from a cheap ls1+turbo. Probably even less.

 

agree with Attilla.

Cutting the entry way to the port is the LAST place you hunt for power in the heads.

 

Times 3

 

Explain a little better what you mean, just too much lift? The xe268 is only designed for 9:1ish and the motor runs outta breath at 5k anyway so I lose a little on the bottom end...(that is assuming my current cam is smaller) Right? Correct me if I'm wrong, but with factory numbers for a 350, this combo adds up to 11.25:1.

 

OK guys, couple more questions, I got the motor apart tonight after work and its got dished pistons, the only way I can describe them is a saucer shaped hole, I checked the bore came up with 4.080, and the block is decked for sure. What head gaskets would you recommend. Also would you guys say that Doom did a good job on his heads (Ported 416 heads thread) as far as porting goes? This will be my first shot at it so it would be nice to have all the pics. I'm sure I'm forgetting something, I'm tired. Thanks