SBC top end build input???

[RITTER]

Alright, I am currently waiting on my Weiand Stealth (I believe it is the 8020) intake manifold, it is on back order till July 16th. I have a brand new HOLLEY 600 cfm single feed vacuum secondary. I have the Lunati 60103LK (Hydraulic Flat Tappet, Advertised Duration 268/276, Lift .489/.504) RPM range 1,800-6,200. A Cloyes double roller timing chain set. And last but not least, I got a set of rebuilt 041 GM heads.
As soon as my intake gets into work here, I will be doing the conversion.

What type of crank horsepower/torque numbers do you think I'll be looking at?

Any other input or suggestions is much appreciated 😀

 

[patmckinneyracing]

What size valves and combustion chambers are in those heads? I have been looking extensively at the Voodoo 268 cam that you have to use in my own 350. My best estimate would be 390-400hp and 425lbs.

 

[84cutspreme]

I believe those heads are 64cc, but don't quote me on it. valve size you'd need to check, came with both 1.94/1.50 & 2.02/1.60

 

[RITTER]

They are the 2.02/1.60 valve heads and 64cc combustion chamber size

The short block is equipped with your standard 4-valve relief flat top pistons with 5cc dish all together, which should put me around 9.6:1 over all compression ratio

 

[patmckinneyracing]

Compression ratio sounds about right. I'm running a 74-75cc head with KB flat tops with the valve reliefs and I've got about 9.0-9.2 compression ratio.

 

[SScamino]

My 350 with a 5cc dish 4valve relief flatop piston is 9.898455 bla bla bla bla the number keeps going lol. You need to use a calcutlator to more acuratley find your compression ratio! Also you said the heads have been worked? Have they been updated so you can run unleaded gas with these heads? If not you'll be pounding out some valve guides. 041 Heads are great but are down about 20-25 hp as compared to vortecs. So with the right work done to them they might make a little less than a vortec but id say a good overall guess would be about 355-365 hp with about 390-400 lbs of torque! Which is pretty good for an older design head!

 

[patmckinneyracing]

I'm gonna have to get my motor dynoed once it's done. Everywhere I go it seems like people just dog the sh*t out of the older iron heads when they probably make more power than what people actually think. I'm running my 882 head's and they have the larger valves and slight port work.

Yes, aftermarket heads do flow better and I'm sure the vortecs might flow a little bit better than modded iron heads, but 9 times out of then, on the street with a cam that is 2-3 steps above stock, your not gonna feel it. Only time you'll notice it is if you go to the track often enough to see the difference on your time slip. If the heads you have work, then wait till you rebuild the motor again or you crack one of them. Why replace what is properly built and working in the first place.

 

[JBreu]

I would gues you'll be around 425 hp or so +or- ????

 

[patmckinneyracing]

Should be right at or a little over 400hp. My current setup has a summit cam and I was making 375-385hp with it. The voodoo is a big difference over the cheap summit cams.

 

[RITTER]

I got the heads super cheap, so that is why I am using these ones. I have read pretty much nothing but good things about these heads. They have been worked over, everything is new. I was going to go with a SummitRacing cam, but people kept telling me not to, so that's how I ended up with the Voodoo cam. Thanks for all the encouragement here, I'm super stoked to get my intake and do the swap.

My next project needs to be getting rid of this 2.14 open rear-end :| and a torque converter