Oldsmaniac

Will be needing a cam for a stock rebuild of a 330 in a 67 Cutlass wagon. Will be 3spd stick, single exhaust, and 308 rear and 10-1 pistons. Was looking at Comp dual energy. I could also get just a cheapo Melling stock cam....what to do?

pmathews

My combo is pretty similar (330 HC, 10.4 compression, 3.08 rear, TH400 auto). I selected a 265DEH from Comp Cams, but it's not working well with 93 octane.

I wanted the 10:1 compression, but overshot, and with this cam, it made the dynamic compression too high. Now I have to be REALLY careful with timing and octane. In hindsight, I should have gone lower on the compression or used a 275DEH.

If you go with a more aggressive cam like a 275DEH, I would go with a steeper rear end. The 3.08 is 'okay' with my cruiser, but I really need something steeper, and with a 275DEH, it would definitely be worse.

Hope this helps...

Oldsmaniac

The cam from Comp I was looking at was their tame DEH255, I am going to use felpro head gaskets and not factory steel shim type. I may end up putting dual exhaust on it but not sure from the start. Just looking for a good performing engine.

pmathews

Looking at keeping dynamic compression in the safe zone, I think a 255DEH would be going in the wrong direction, so make sure you check the dynamic compression calcs before buying that cam. It's the intake closing event that will make your dynamic compression sky-rocket, and I think the 255DEH will make that worse, but I'm not an expert.

I would ask CutlassEFI for his recommendations, he's super helpful.

DoubleV

Then you're going to want dual exhaust. Even on my stock weezing 307 it made a big difference.

Does your motor have pistons advertised as '10 to 1 pistons' or is that your actual calculated CR?

Oldsmaniac

Replacement pistons from egge advertised as the higher compression stock pistons. They have a decent dish to them still with advertised CR 10 to 1 ratio. Ya on the duals.

DoubleV

I would measure your true CR then. I personally don't know what the manufacturers assumptions are when they advertise their pistons as 'X to 1' being there are so many varied factors. If there's an industry standard for assumed measurements, I don't know what they are.

pmathews

Here's a picture of the Egge piston (L2228-8) that I used -> http://www.supercarsunlimited.com/330-Piston-d2293.aspx

FYI, When we ordered these (December 2013), Egge was running short on supply of the High Compression pistons.

Another point, I didn't 'personally' measure my compression, 10.4 was reported by my engine builder. He has a great reputation, so I would trust his calcs over mine. He did some minimal cleaning up of the mating surfaces of the block and heads, but probably not more than .005 -.010 on each surface. We used a standard Felpro gasket which added height.

In hindsight, I should have asked for the measurements of the piston depth in the bore since aftermarket pistons will sometimes be shorter. Guess I'll need to pull the head to measure it (one day).

Oldsmaniac

Thats the one I used, no cleanup on deck, minimal mill for cleanup on heads, #4 heads. Rods were serviced so technically they are a tad shorter = a tad less compression possibly. What is your ignition timing set at idle? Factory settings like 5 degress BTDC? Engine has not been started assembling yet... still a box of parts.

pmathews

I'm running 8 initial, 28 total, with 10 degrees of (manifold) vacuum advance. I am also running rich at idle, part throttle, and WOT to keep any lean condition in check. Spark plugs look pretty clean, maybe a bit of dark soot due to the rich mixture, but definitely not lean.

Did you get a chance to measure the depth of that piston in the hole? That would be valuable info, I don't want to pull the heads to measure (haha).

cutlassefi

I'd do an Erson Viking 100H.
Adv 290/290, 222/222@.050, .477 lift. The comp stuff doesn't have enough off the seat time, that's why even running 93 is still a problem.

Thanks.

Oldsmaniac

Not to be stupid but where would I get this cam? Have been searching the web and havent really found it... Thanks for the info!

jag1886

My EGGE pistons where a good ways down the hole, you can adjust deck height to get the compression where you want it. I believe they took .020 off the block and mine are still .005 down the hole.

pmathews

That's good info, I'm guessing it's reasonable to expect my Egge pistons are .020 down the hole with my .005 decked block. That doesn't help with quench (.020 + .040 gasket). I'm dying to measure mine, but I really don't want to pull the heads to see without a really good reason.

Regardless, I'm just pi$$ing in the wind without the hard data to calc static compression, but I'll get there one day. In the meantime, I'll keep running Torco and retarded timing to keep things safe. For those that don't know, Torco is a pretty good octane booster.

DoubleV

Dang that's pretty low. It's gotta totally suck the life out of your engine no?

cutlassefi

No problem. You can get it from Erson or me. But I'm normally cheaper than even if you bought direct from Erson. They don't sell to the general public as inexpensively. They support their dealers like me.

pmathews

Yeah, 28 total isn't great, but surprisingly, it still runs pretty good. If I run Torco, I can bump it to 32 total, that's what I'm doing now.

In hindsight, I should have bought my cam from cutlassefi