Mmmmmmm new toys

[SUX2BU99]

After much discussion, thought and research I finally was able to purchase my new cam and heads. The cam and lifter kit I got back in September. And for Christmas, I treated myself to the heads. Cam is a Comp Cams Xtreme Energy 268 and the heads are Dart Iron Eagle S/S with 72cc chambers, 165cc intake and 1.94/1.50 valves. Doesn't sound too crazy but they make power like stock Vortechs (a little better), can take a bigger cam, come assembled complete with ARP studs and were cheaper than buying new Vortechs. I could have gone with larger valves, smaller chambers and bigger intake runners but I was really wanting a strong puller that makes some good HP to around 5500. I didn't want a soft bottom end. I got that now, along with a wheezing top end lol



These will be going in my mostly stock 60-over 350 that's in the truck right now. Has late 70's truck heads and a really mild cam. Has a Dart dual-plane intake, headers, true duals with no cats, and Edelbrock 625 carb on it though so I feel that 350 HP should be easily attainable and from what I've seen, 375 HP is around what it should be making at the crank.

One thing I wonder though is would there be any advantage to polishing the combustion chambers? Not porting, just polishing.

[VileZambonie]

You should port match your heads. Leave the combustion chamber alone. Odds are the castings are good enough in that aspect. If you don't want to get too crazy at the very least port match the heads to the gaskets and then port match the intake manifold to the heads once they're bolted on. You wouldn't believe how far off your intake can be!

[SUX2BU99]

Not a bad idea. How exactly does the intake to head port matching get done? Can the gasket ports be used as a reference for both the head and the intake to port match to?  I would think so since the gasket is going to sit in the same spot whether it's lined up with the head bolt holes for the intake, or with the intake bolt holes for the head. No?


Here's a few other pics:

[VileZambonie]

Here's a nice easy method:

Port match your heads to the gaskets. Once the heads are installed take the intake manifold end seals (you know the ones you'll throw away anyway) and lay them in place. Then position the intake gaskets so they are properly aligned. On the side of the gasket facing the heads place a long piece of duct tape (sticky side up) under the intake gaskets. Now position the intake and lightly snug it down. Wrap the tape tightly to the intake so that when you remove it the gaskets come up with the intake manifold and then flip it over. Your gaskets will be in the position where they mate with the head. From there trace out the gasket with a fine point sharpe and grind away.

Some people drill holes in the intake to use as alignment dowels but I'd rather not poke holes in my manifold when duct tape works just fine.

PS where's your guide plates and roller rockers? 

[SUX2BU99]

Can that be done on the bench at all? I'll be having a shop install the cam and heads for me. I got a quote of approx. 2 days labor plus materials from a performance shop. I would think 1.5 days max, no? Moving quicky and efficiently, I would think a competent person should maybe even get it done in one day.

I have roller-tipped stamped rockers on my truck right now. Figured I would reuse them. Guide plates I wasn't considering. I'm not trying to make this a 6000+ rpm screamer   lol

[VileZambonie]

Can it be done on a bench? I couldn't really think of a better place to do it. If you have screw in studs already guide plates and hardened pushrods are a smart idea if you are using roller rockers or if you want to upgrade down the road.

As far as doing the heads and cam in a day I'd be a little concerned about the attention to detail.

[SUX2BU99]

Got ya. I meant on the bench as in not having to install the heads on the motor first. If I port match the intake and heads, I'd rather do it on my work bench before my truck goes to the shop for the heads and cam install.  I don't have any provision to yank the motor in my garage and the shop will probably install the heads and cam with the motor in the truck.

Hmmmmm now that I think of it, the intake I want to use is on my truck. I'd have to pull it off to do the port-matching. I would then not be able to get my truck to the shop, unless I reinstall the intake again I suppose.

My entire top end valvetrain will be new, save for the rockers. I'll get new pushroods. I have everything else. What do you figure a save redline will be for this? I was hoping for it to make power to 5500 rpm of which will probably be my shift point, with a redline of 6000. Heads come with 1.25" valve springs, good for .525" of lift.

[VileZambonie]

You'll have to port match with the heads installed on the engine. There's no other way to do it unfortunately. You should ALWAYS check your port match they are almost never on...

You'll know when to shift your truck when it stops pulling. Just shift right before that point otherwise you'll be just reving and not making any power. I would guess somewhere around 5-5,500 RPM but other factors will determine. What are you running for exhaust?

[SUX2BU99]

Hmmm well I might have to skip the port matching then unless I can find somebody who knows what they are doing. The big name performance retailer told me it would be a waste of money on my combo.  For exhaust I have typical long Hooker-style headers, dual 2 1/4" pipes, h pipe, no cats and Dynomax Ultraflow mufflers with 3" Magnaflow tips.

[VileZambonie]

The big name performance retailer told me it would be a waste of money on my combo. 

What did they say would be a waste of money?

[nova801428]

port matching is practically free...it is if you have all the tools.  I would say it is one of the cheapest and best things to do to an engine.  It's like changing your oil...but much harder.  I had a good link but lost it.

[SUX2BU99]

They simply just said because of my 'combo'. I guess it's not quite exotic enough to them to warrant the work.

[SUX2BU99]

Would a dremel be up to the task of minor clean up work? I saw a casting ridge in one of the water jackets I want to remove and a bit of lumpiness in another port.

As a point of interest, here are my existing heads (stock smoggers), roller tip rockers and the headers that were all on it when I bought it:

[77c15]

What is your cardomain site address?

[VileZambonie]

Port matching isn't done for just "exotic" applications. Unwrapping an intake or set of heads and expecting the ports to just line up is ridiculous and rarely happens. I would ask anyone bothering to do any engine upgrades why they wouldn't do this? What's the point of replacing a cam or putting on headers or different heads only to have your intake ports send air crashing into the side of the head?

I just port matched my 454 and they were off about 1/4". It literally takes an extra 5 minutes to just check them when you are about to install the intake manifold using the method I described. Why wouldn't any DECENT engine builder check?

I wouldn't be concerned about casting flash in the coolant ports but a decent carbide dremel will clean it up.