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Discussion Starter · #1 ·
got a coupon, I want to put the flat hood back on the 66 and thinking of keeping the 350. basic smog mid 70s 350 with basically a Elgin/performer cam. just looking for a little more umph, rpm intake, wide ratio 3.55 gears. it ran fine without the 142 blower, just not a lot of guts.
I had to get a credit card because I have no credit, figure the 1st purchase might as well be something to show for it. (will pay it off when the bill comes) Jim
 

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What kind of power increase are you looking for? Every 350" SBC I've ever played with, responded to compression. If you have a flat top motor, these will get you close to (or maybe at) the factory 10.25/1 CR. If your motor has dished piston, you're probably still going to only get to about 9/1, which is just not enough compression for a small block, not to mention those dished pistons have terrible squish and quench. That's been my experience. I've done two low compression big chamber small blocks, late 70's was a '74 Laguna, we swapped on a set of 64CC iron heads from an earlier L48, short block had stock dished pistons, and swapped in the L79 cam, ran OK, but nowhere near enough increase in power worth the swap. The other was around '81-'82, '73 Vette L48 (basic 8.5/1 dished pistons 350), basic rebuild/freshen up, all we did was swapped in 11/1 pistons. Same stock 76CC heads with a lite port cleanup and L46 cam Difference was night and day. Crisp throttle, great vacuum, pretty much everything you'd expect from raising compression via piston swap.
 

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Discussion Starter · #5 ·
without the miniblower it ran fine, just didn't have the get up and go. my camaro had a stock sb400 with just a intake, headers and would take off with the tires spinning with ease if I wanted and that's with a auto and 3.07 gears. I could just swap to a early set of 461 heads but I was thinking the newer heads have better ports, and combustion chambers. jim
 

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without the miniblower it ran fine, just didn't have the get up and go. my camaro had a stock sb400 with just a intake, headers and would take off with the tires spinning with ease if I wanted and that's with a auto and 3.07 gears. I could just swap to a early set of 461 heads but I was thinking the newer heads have better ports, and combustion chambers. jim
Just sharing my experience. You can go about it however you see fit. I tried the small chamber heads on a stock dished piston shortblock, wasn't worth the trouble.
 

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Discussion Starter · #7 ·
so keep the blower, and save my $$$? jim
 

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so keep the blower, and save my $$$? jim
I wouldn't drop $2000 on a head swap on a stock dished piston shortblock, that's all I'm saying. I'm assuming this engine has never been apart? Most likely that's why you've been able to run some boost, although a 142 is probably only giving you about 5PSI?
 

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Discussion Starter · #9 ·
the motor gotten new rings bearings and hand lapped valves years ago. it's been so long, I dont remember if it's std or 030 over. i remember it's got the 4 eyebrow pistons. jim
 

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the motor gotten new rings bearings and hand lapped valves years ago. it's been so long, I dont remember if it's std or 030 over. i remember it's got the 4 eyebrow pistons. jim
Most likely you rebuilt it with flat tops then, big difference. I'll be honest, I'm not up on SBC heads. My input to this discussion was strictly from looking at '70s small block as referenced. Your CR is probably about 9/1 as it sits then. 64CC chamber will push the CR to about 10.25/1. I kinda think you'd get more gain putting a short duration roller in it.
Keep us posted whatever you decide
 

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Looks like a nice kit, comes with rockers(?) and the longer-than-stock pushrods that Eddy requires. I believe the E-Street heads require the Vortex style intake. If there is a Performer RPM version it will work with a standard small block intake. The heads alone are about $1200, so consider if you don't do the heads but decide to do the roller came and you don't currently have good rockers, good pushrods, then it's an apple to oranges comparison on pricing.
 
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