I've been doing a bit of research, and thought I might just ask my question here as I'm sure there are some knowledgeable folks as far as engine dynamics go.

I have a 10k mile Goodwrench (old stock Targetmaster) 350. I bought the car with a freshly installed edelbrock Performer RPM cam, RPM air gap intake, Demon 650 double pumper, and Edelbrock T.E.S. Headers with Flowmaster cat back. Gutted cat. It's a 5 speed with 3.42 gear ratio. I think the previous owner must've liked Edelbrock....

I want a hot street car, I like the super choppy idle, it attracts a lot of attention. If the car ran-out as good as the car sounded, I'd be happy. However, the engine is kind of a dog with the 8.xx compression and that cam choice. It's gotta heck of a rumbly idle, but its "bark" is a lot meaner than the "bite", if you know-what-I-mean. I feel like the cylinder heads were really holding this motor back, 76cc smoggers (882 style). It doesn't want to idle well, it does want to rev, however it falls on its face around 4000 rpm. Just the wrong cam for the current engine, way too much duration. Or something.

I just purchased a set of World Products S/R TORQUER heads with 67cc chambers, which should bring my compression up more in the 9.5-1 range. I'm thinking bout some light port work when I get the valve job done as well. I think they are 170cc chambers. I wanted some Vortecs, but was concerned with valve lift and of course it would require swapping intakes, and these Torquers I found relatively cheap. Is the compression what is hindering my current engine? 2.02/1.06 valves help as well?

Will these heads be enough to "wake" ( or take out the dog-running part) my engine up or should this cam go? I don't really have $ growing on trees, but I understand this cam grind is considered an "old style" or a bit lazy. I was looking at the following for cam choices:

Lunati VooDoo
20703 (268/276, 489/504 110LSA) or
20704 (276/284, 504/525 110LSA)
Or even the one of the Comp XFI cam grinds,
12-366 (268/280, 520/515 113 LSA) (w/1.6 rockers) or
12-367 (280/290, 520/515 113 LSA) (w/1.6 rockers)

But am really ignorant as far as understanding what would work best. I don't want to change cams if not necessary, if the current one will work well with my new heads, that's great. But I wanted to ask around to see what more knowledgable people think about my situation.

I know there are many different cam manufacturers out there, these are just examples.

Hot Street car, some drag racing, maybe some track days and autocross, weekend warrior type.

thoughts/opinions? Thanks in advance for any/all advice. Apologies for the novel.

I also have a set of 1.6 comp roller rockers but haven't installed yet, thoughts on this after head swap?


Specs on current cam: Edelbrock Performer RPM, pt.# 7102
308/318 (234/244 @50) 488in/510ex lift. 112 LSA

Engine specs:

Bore x Stroke: 4.00” x 3.48”
Compression Ratio: 8.5:1
Recommended Fuel: 87 Octane

Block: Cast Iron, 2 piece rear seal, 4-bolt main caps part # 10066034, casting # 10066036

Crankshaft: Nodular Iron 1985 and older flywheel bolt pattern. #3932444
Connecting Rods: Powdered Metal Steel #10108688

Pistons: Cast Aluminum , 8.3435cc (dish) pistons-#1251410

head gaskets used measured .026" to .028" thick x 4.100" bore
Deck clearance: .020". - .050"
Cylinder heads are cast iron with 1.94 in. intake valves and 1.50 in. exhaust valves, 76cc combustion chambers, and 7-bolt style exhaust.flanges.
Cylinder Heads: part # 14034808, casting #33417369, Cast Iron,
Valve Springs: #3911068

3/8” pressed in rocker studs
Combustion Chamber: 76cc
Valves: .194” Intake/ 1.50” Exhaust
Rocker Arms: Stamped Steel, 1.5:1 Ratio

 

The lesser of those 2 Lunati ones is probably the best choice of the ones listed.

Yes use the1.6 rockers; but make sure the valve springs are at least 1.44" dia. No 1.25"ers.

 

Thanks sofa for advice.

What are your thoughts as to the combination of parts with the new heads? Your opinion of the Performer RPM cam with the 67cc World 2.02 heads? I know they are basically a "stock replacement", hence the"S/R" designation, do you think the increase in compression and flow will be significant compared to my current setup?

Or is this one of those situations where "less is more" in regards to cam shafts? I don't really want to change cams unless this setup won't be much different than my current setup. Was/am hoping it will wake up and run like it should......

 

It's more than that. Edelbrock's cams are honestly not very good grinds. You will need to step down on the cam and pick a better grind more suited for your application. A properly matched cam for this setup is most likely not going to sound very wild, FYI.

If you want a true and honest choice of Lunati's grinds, you need to call Steve directly @ Lunati. There are many more cam choices than the ones you've listed; many of which will be a better option. He can also adjust the grinds to tailor your needs to get a little more out of them for your ideal setup.

 

That cam you have now, was for old folks like me, who liked a rumpity idle, and didn't know better when we were young.

Since you're gong to have the heads off, ...spend the money for cam and swap items, might also want to look into a good roller timing chain as well...get it all done at once.

Personally I'd ask SFD what his choice of cam would be with your set up, IIRC, he had/has a good knowledge of COMP and their grinds...he's getting older too, but he probably hasn't forgot

 

Comp's well known grinds are also outdated in comparison, and Lunati currently has all the most recent revisions because Harold Brookshire was the person behind both.

If he wants to get the most out of things, getting a shelf cam is cutting corners. I say this in every single thread that is "what cam should I run" because unless it's tailored for your motor - you ARE cutting corners and guessing. Considering the price difference is virtually nonexistent, I really don't see why anyone bothers with shelf cams anymore. There's simply no reason for it with the competent cam designers available today. Even mild motors strongly benefit from camshafts designed for their needs.

 

I didn't call, but I did email Lunati a while back, they recommended the 2 VooDoo grinds I listed above. I also emailed Crower, they had a bit more aggressive cam picked out, believe it or not.

The XFI series I've had my eye on ever since I read that article ( ahem, advertisement, I'm sure) where they tested it on a carbed motor with good results. I've seen some reviews stating they are hard on valvetrain, but people seem to like them.

Both of those cam types are a lot more "modern", probably more suited for a max effort fuel injected type hot street build, than what I am running. I've plans later down the road, I purchased 11SEC91Z's old 388 shortblock last summer and have high hopes for it someday.....

Emails however were last year sometime, when I thought I was going with aluminum heads, also before my rear grenade'd, which had a 3.73 gear ratio. I just rebuilt it with a 3.42 ratio.

They might have a different suggestion now, little less aggressive parameters than the initial plan. Pipe dreams...