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engine rebuild help

890 views 8 replies 5 participants last post by  99 to Life 
#1 ·
ok first is what I have to go with and second is what I need help on....
first I have a sbc 350 bored 40 over the block is 3970010 the head is 3998991....the crank is 3932442 I have flat top piston new speed pro lifters and rods.....ok hope Im doing this right but I'm looking for a cam I love the sound of thumper cams but never delt with them it's going in a 78 builk regal mostly for the street and trying out the strip once and a will the strip last but would like imput of what I am look for I have no idea on the cam....thanks so much vince
 
#2 ·
gaurdian101 said:
ok first is what I have to go with and second is what I need help on....
first I have a sbc 350 bored 40 over the block is 3970010 the head is 3998991....the crank is 3932442 I have flat top piston new speed pro lifters and rods.....ok hope Im doing this right but I'm looking for a cam I love the sound of thumper cams but never delt with them it's going in a 78 builk regal mostly for the street and trying out the strip once and a will the strip last but would like imput of what I am look for I have no idea on the cam....thanks so much vince
Others will chime in on a cam spec of their liking but I can tell you to stay away from the Thumper cams if you want a good performance cam. Now, if you are just looking for a "tough" sounding cam with no performance, a Thumper is the way to go but there are ALOT of other choices out there that will put the Thumper to bed.
 
#4 ·
gaurdian101 said:
ok first is what I have to go with and second is what I need help on....
first I have a sbc 350 bored 40 over the block is 3970010 the head is 3998991....the crank is 3932442 I have flat top piston new speed pro lifters and rods.....ok hope Im doing this right but I'm looking for a cam I love the sound of thumper cams but never delt with them it's going in a 78 builk regal mostly for the street and trying out the strip once and a will the strip last but would like imput of what I am look for I have no idea on the cam....thanks so much vince
That crank shows up as a cast 350 SBC, the block is a 4" bore SBC so those two things are fine as long as the crank journals are good or will clean up by being turned at the machine shop. Same w/the block, it needs to be checked for cracks, deck flatness, main bore alignment and to be measured to see what needs to be done to the bore.

Now those heads are going to be the bottleneck in this build. They are the large chamber heads and often came w/the small 1.72" intake valve. If that is what you have, they should be put aside and a better set of heads found.

For the cam, my advice is to stay w/a strong torquey cam and let the sound fall where it may. Sound is just that- sound. You want power.
Another problem w/wanting the "sound" is it will also mean you will need a looser torque converter, lower rear gears and/or a swap to a TH700R4 or a TH2004R trans. Headers w/a dual exhaust system is also needed, along w/a performance intake like the Edelbrock RPM and a carb to match the combo.

You also need an HEI-type distributor and good wires, along w/the rest of the parts that go into an engine- covers, timing set, oil pump, rings, bearings, all the hardware, gaskets, etc.

These are just a few things off the top of my head, but the biggest thing that will make or break this build are the heads. Always use the best heads your budget will allow, because that's what makes the power (along w/the cam) in a SBC 350 engine.

Northern and Competition Products have catalogs (as do many other discount parts suppliers) that you should look into.
 
#6 ·
LUNATI voodoo 262/268. Great Cam for stock to mild rebuilt 350 engines. Friend of mine has one in a 355 and it pulls ridiculous for a small Adv duration cam. Has a smooth idle but has a slight lope in gear. This would b great for your engine. For a little MORE thump, go to voodoo 268. Both are Great cams for your engine.
 
#7 ·
gaurdian101 said:
I should also said i do have a msd ignition and have a Edelbrock RPM manifold no carb yet the heads are double camel hump I know there not the best heads but there what I've got to go on for now.....
The c/n 3998991 you gave are not for double hump heads. They should be large chamber (about 76cc) w/the small 1.72" intake valves. Used on the 307 and often truck 350 SBC engines.
 
#8 ·
LUNATI voodoo 262/268. Great Cam for stock to mild rebuilt 350 engines. Friend of mine has one in a 355 and it pulls ridiculous for a small Adv duration cam. Has a smooth idle but has a slight lope in gear. This would b great for your engine. For a little MORE thump, go to voodoo 268. Both are Great cams for your engine.
 
#9 ·
Here is a link to a site that will help you with compression ratio.
http://www.rbracing-rsr.com/compstaticcalc.html That is something to consider as well IMO. You are 40 over with large cc heads, your compression is going to be on the lower side. If you stick with those heads and have small exhaust valves, you might want a came that has a longer exhaust duration to help the engine breathe. Just things to consider. Also your trans and rear end will gravely effect your cam selection, especially if you want a street strip.

Lastly I noticed you have an RPM manifold, so if you keep that I think they are designed for 6500 rpm range usually, so a cam with a proper lift would accommodate that. BUT your heads will definitely need worked or replaced.

I am just trying to point out some other factors. Cam selection is more than
just sound and bigger isn't always better.
 
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