[TheCiscoKid]

I have a 76 sbc with RV cam, performer intake and carb.This motor new had a low CR,so looking to vortec style heads, but would like to keep my intake.I think Pro Comp aluminum heads will take my intake.Are these heads any good? I don't really care if it's aluminum,so if you can recommend a head,please do.From what I read today a dif cam might be better too.I won't be rev' g over 4000, just want a driver motor. Cisco.

[DoubleVision]

Don't waste your money. You get what you pay for. If your just wanting a basic head to up the compression and give it more breatheable power upstairs then you the basic world S/R Torquer heads are for you. These are stock replacement heads that breathe better and have a smaller chamber to raise the compression ratio, you'll want to use them with a thin head gasket. Even if you install them and get it dialed in correctly regardless of whats been said it will still be sluggish until you get some gears in it.

[idontdrivericeieatit]

In a word no I have never seen or heard of a set of.pro comps out the box being good they all need work if u do have get them I would not for any reason but if u do then buy them bare the pro comp parts also suck take them to a machine shop have everything checked and fixed have ports cleaned up and bowl work make sure check vavle guides and every bolt hole in them ive seen them where no two vavle set at the same height I wouldnt run them go with something you know is going be ok

[cdminter59]

If you need a set of Vortec heads check out these Vortec heads at Jegs.Chevrolet Performance 12558060 Chevrolet Performance Cast Iron Vortec SBC Heads. Vortec Heads require a Vortec style intake manifold due to its improved manifold mounting flange and gasket design and raised intake ports. They also requires the use of self-aligning rocker arms.

[ap72]

4 years old...

[cdminter59]

Check out this website for complete kits for Vortec heads. Scoggin Dickey Parts Center SD8060KIT - Vortec Head Kit, Edelbrock Performer Intake SDParts.com - 1-800-456-0211 Jegs has their Vortec head kits too but didn't include the rocker arms. Check your camshaft specs to see if it is simialar to a camshaft like this. Lunati 06105 - Lunati Hydraulic Flat Tappet Camshafts - Overview - SummitRacing.com

[cdminter59]

Darn didn't even pay attention to the date! Oh well

[hcompton]

I am cheap so I always look for the best deal.

You wanted none vortec heads right. Its the only way to keep your intake. Grinding is ok for regular stuff but for motor home just get the right stuff. The tow bill for a small oil leak would cover a set of new heads.

Sorry for the ebay link but this guy is the cheapest I have found.

Vortec bolt pattern 58cc
Performance 327 350 400 Chevy Cylinder Heads 187 SBC 500 Springs | eBay

sbc bolt pattern 64cc
Performance 327 350 400 Chevy Cylinder Heads 187 SBC 500 Springs | eBay


I think they are complete and ready to bolt on.

419.00 for a set of heads with 2.02 valves and choice of casting numbers. My local machine shop would charge me that much in labor. My area has high labor cost for machine shops.

Not sure about the cam. But motor homes are low compression for a very good reason. High compression engine get very bad mpg. Try to get them with just a little more compression. 10:1 in a motor home my leave you with 5 mpg. But alot more power so a little foot control could ease it out onto the highway with out putting it to the floor. Might help even it out. Probaly not...

Hope this helps.

[hcompton]

LOL I did the same thing... This is an old post if your ready for the first time.

[ap72]

Originally Posted by hcompton

High compression engine get very bad mpg.

couldn't be more wrong if you tried. The exact opposite is true. Higher compression gets better mileage.

[hcompton]

Originally Posted by ap72

couldn't be more wrong if you tried. The exact opposite is true. Higher compression gets better mileage.

Dude read some books or something. Try that new thing on the interwebs google they call it.

[ap72]

Originally Posted by hcompton

Dude read some books or something. Try that new thing on the interwebs google they call it.

Dude, I read all the books or something. Its called efficiency, it goes up with raised compression. Any basic book on 4 cycle engine design should cover it in the first or second chapter.

Try doing some legitimate research instead of reading all the hearsay passed around on forums and spread with google.

[hcompton]

Originally Posted by ap72

Dude, I read all the books or something. Its called efficiency, it goes up with raised compression. Any basic book on 4 cycle engine design should cover it in the first or second chapter.

Try doing some legitimate research instead of reading all the hearsay passed around on forums and spread with google.

I have changed the cr in every motor i have built It always needs more fuel. Usally have to go up a full jet size on the carb or larger injectors. The entire reason they make 8:1 engines is because the use less gas. They surely dont make more power. Many big blocks are low compression from the factory for that same reason. High compression small displacement engine use less gas than large lower compression engine in some cases.

If what you say is true I would be able to lower the jet size in the carb. when i increase the compression. This is a very big issue among RV owners today. That is why turbos are such popular upgrades. You can keep your foot out of it on the highway and run a 7:1 compression engine at low rpm and no boost. then step down if you need to get up a hill and only burn lots of gas at that point.

I was doing this before google! Just an FYI.

but this is an old post so stop being silly and offer the guy some real advice even if its 4 years late. Someone else may be able to use it.

[hcompton]

AP72 let me help you out.

Performance Tuning in Theory and Practice,Four Strokes: A. Graham Bell: 9780854292752: Amazon.com: Books

Performance Tuning in Theory and Practice,Four Strokes: A. Graham Bell: 9780854292752: Amazon.com: Books

This is the source of engine tuning. Math is a little difficult but has ways to calculate every part of an engine and know everyhting long before it is built.

From lawn mowers to indy cars they all apply to the base math of fluid dynamics. the math in this book was used to design all engine by all manufactures. Anything you see ont he net that does not agree with bell. The internet is wrong. Ask a real engine designer. If you build engines from scratch this is how you can calculate everything. Not very useful for chevy/ford v8 as all the math has been done and you just need to grab the right combo.