Best 18 degree head out there?

[jmarkaudio]

Not quite that big, how about my 461CI SBC?

[Craig W.]

Can you pass along any tips on building an SB2.2 motor? Any hidden pitfalls or unforeseen costs?

Heads, intake, rockers, cam, headers, gaskets, studs, valve covers...what else has to change?

[jmarkaudio]

Pistons and cam up everything is different. That one also has SB2 lifter bores, but not a requirement.

[Craig W.]

Do most SB2 intakes have provisions for a normal distributor?

[jmarkaudio]

The intake contacts no water or oil, the SB2 uses a valley tray and with a standard deck height block a normal distributor works fine. On the Dart Iron Eagle and Aluminum blocks, they changed the distributor angle 1˚ that moves the distributor over a little. On a 9.300 deck it requires a slip collar distributor and milling the hole in the valley tray a little. On the 9.5" deck aluminum block in the picture, it required more milling and a custom collar to seal the hole.

[jmarkaudio]

A few more pics over here.
http://1320techtalk.com/viewtopic.php?t=1507

[hugger73hatch]

i just cant figure out why for the cost when someone builds a 18 degree sbc, they dont build a big chevy?

figure on most components being close to same price(crank,heads and block might be slightly more) but for power levels why run a 750 hp sbc on the ragged side when you can run 800 hp with a 540 or larger soooo safely!!!!

750 hp sbc requires lots of cam and compression,and thats getting close to maxing out motor.....with 750 hp it can be done with bbc 540 cubes with 10.5:1 compression and so so cam.but here is the kicker, the big chevy will gulp up a big shot hit of nitrous(400 EXTRA HORSEPOWER) nooooo problem!!! id be scared to put 400 shot of spray in a sbc

Some people just like small blocks. Besides, lest say you are running a 434 or 440 small block. Throw on a set of 18 degree heads, and that motor now has better intake runners than a 24 degree big block, plus big block sized valves. Your little 434 or 440 (and to think these things get as big as 472) just threw it's "mouse" stigma out the window. It now has a big block attitude and power output, and like above, not the weight. And you can make 750, or 800 with 12.5 compression and run e-85 on the street. But, i will stick to my big blocks. Mine is only a 496, one day I will grow up and build something in the 600 cu in range for a pump gas motor.

Also, there are some classes that are for small blocks only. I am a small block guy myself.

[Craig W.]

The intake contacts no water or oil, the SB2 uses a valley tray and with a standard deck height block a normal distributor works fine. On the Dart Iron Eagle and Aluminum blocks, they changed the distributor angle 1˚ that moves the distributor over a little.

Yeah, I should have said valley tray.

I've got an Olds Rocket block, so I'm in good shape on working with the distributor issues it brings with it. At least something I have would transfer over to SB2.2

Great looking engine. Had it on the dyno yet?

[jmarkaudio]

Picked up the dry sump mandrel today, need to decide on a pump this week. I should get it finished up and in the car for a shakedown and break-in, then I'll pull it for the dyno. The heads are purpose built by RFD from bare castings for this project, not cup takeoffs. Looking for somewhere between 900-950, the heads would probably support close to a 1000 with the right dual carb intake. Time will tell...

[soslojoe1970]

Have a nice 850hp sb2 motor. Only problem i have really had is the intake valve pocket is real close to the inside of the top ring land and have cracked there and lifted the top, on nos motor. Makes good power to 8600 rpms and on a 406cid. Single carb 6" cowl hood.

[Craig W.]

Was this a custom nitrous piston or a circle track style piston? How much nitrous?

[jmarkaudio]

SB2's are generally not a nitrous friendly head for more than about a 150 kit without combustion chamber mods, done by the right head porter. The combustion speed in an SB2 is fast, which is why the timing is usually under 30˚, and not the way to go with heavy nitrous. Not to mention what you found with the pistons. However they do seem to love a turbo on top....

[soslojoe1970]

I sprayed 300 all day long. Only had problem when stepping up to 500 and thinking i would just run it fat to be safe. Now I see fat is not so safe. When I had a tight nos converter i only ran 25 degrees timing and retarded to 10 on the 300. I now have a high stall to run more on motor and it kept going faster as I increased the timing. Now running 37 degrees timing, with 1600 more stall speed. Car runs 5:80's on drag radial in 3000lbs car on motor. Runs 5:20's on 300 kit.

[jmarkaudio]

37˚ is insane for an SB2, very strange.

[soslojoe1970]

I raced in a race recently which was at a 5.95 index. I had to retard timing about 7 degrees to slow it down. It killed about a .1 and 3 mph ish. 1st pass was 5.945 5 degrees retarted, 2nd pass 5.962 at 2 more degrees retarted. My engine builder says same thing... thinks its high, but said let the motor tell you what it wants, so I kept advancing 2 degrees untill saw no improvment then backed it a couple.????