Thread: newbie help building engine

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Hello all. I'm trying to help out my brother with his '51 rat rod Chevy pickup. He put in a Chevy small block 350 (3970010). He's looking for a cam with a nice lobe but still realistic on the roads. From what i have researched online and magazines i need alot of info to figure out what cam is right for me. Here is what i was able to grasp.

Engine is a sbc 350 v8 block 3970010
Heads are 3998920 1.94 In 1.5 Ex 76cc
I believe 8:1 compression
edelbrock 4 barrel carb 600cfm
4 bolt main
intake 340261

He's looking for low to mid range rpm cam with a nice lope while keeping the cost down. Now i have stumbled across a site were they installed a comp cam hydraulic roller xr276hr, 180cc rhs heads and 1.6:1 pro mag rockers. Sounds nice although the price is out of my range. He would like to keep this install under a $1000. Can any engine enthusiasts shed some knowledge and help me figure out what exactly i need. Thanks

Just to clarify, you're not rebuilding the engine, or even tearing it down, but just throwing a cam in it? Is that right?

Some required reading:

http://www.crankshaftcoalition.com/w..._compatibility

Sorry about the confusion Rspears, my main goal is to do just a cam swap which to me feels like rebuilding . I hate being a newbie haha

Keep the lift under .5

Comp cam 268 has a nice lope and is very streetable with every thing else being stock.

1gary, i read the artical you send me. So if i get a cam that will bump my compression to 8.5:1 i wouldn't have to change anything else ?

With that low of compression, cam selection is limited... I'd suggest you go to the Comp Cams web site, they have a free download called "Cam Quest". If you enter the correct information, the program will suggest some cams..... Much more accurate then guesswork.....

Is it worth working with such low compression? Would it make more sense to bump up the compression? I feel like that would cost me at least 2 grand

Originally Posted by mikesaik

Is it worth working with such low compression? Would it make more sense to bump up the compression? I feel like that would cost me at least 2 grand

Probably not if you're on that tight of a budget....along with zero decking the block, you'd also want better pistons, some head work, and a lot of other things.... Best thing to do IMO like I said is to check out the Comp Cams program and see what they suggest for a cam that is compatible with the engine. A cam can't single handed take an engine from pooch to pounder, takes a lot of parts that compliment each other to make an engine efficient. Or, you can go like a lot of others and just stick some worthless "Poser" cam in the engine and let it lope!!!! Hope you don't choose that approach, the results are very disappointing!

Thats why i'm asking you guys on this forum haha i want to do it right the first time around. I'll check that cam quest out and i'll post the results.

The point of the provided link I posted in summary is too big of a duration on a low compression engine makes it preform worst.The days of just sticking in a cam are long gone because we know so much more about cam timing,how that interacts with compression ratios,formulas about SCR's and how to use DCR's because of pump gas,how to use aluminum heads for a increase in SCR's,sizing intake runners for the c.i. of a engine,targeting a .045 quench and piston types to get there.

The cam quest will only give you answers in the point of view from cam use and there is a ton more to it than that.

What is the hp goals??.

As long as its a gain he will be happy. Stupid question but that engine has solid lifters right? Hydraulic came later down the road?

No, the engine is flat tappet hydraulic lifters..... not to be confused with hydraulic roller lifters....