DNA Motoring CYLH-SBC-350 Aluminum Bare Cylinder Head Compatible with Chevy SBC 302/327/350/383/400

Out of the box, I was throughly impressed. Packed very well, no damage. Using a Machinist's Straight Edge, I checked the deck surface; spot on. All guides feel fantastic with the valves I purchased seperately. I lapped every valve to check the seats; once again......spot on. Ran a tap through every threaded hole; no issues. Very little casting flash inside the runners. Not required by any means but I spend some quality time with a Christmas tree burr and cartridge rolls just below the seat into the runners (smooth the transition) and smoothed the aforementioned casting flash. These heads show a ton of potential. I can't wait to get them on my SBC build!

Todo ok

Looked to be very nicely manufactured. Just came in as straight plug, not angled.

Nice heads! I blew a head gasket on my 67 Corvette and decided it was time to upgrade to aluminum heads. These heads are the same casting as AFR “As cast” for 1/3 the price. Of course, you have to add valves, springs, valve guide plates, and seals, but they are still a good buy if you do the assembling. They needed quite a bit of flashing clean up. Using cartridge sanding wheels, I was able to get them smoothed out for flow and very clean. I put new springs on and lapped the valves. Installed height was 1.70 just as stock. They were incredibly flat when the arrived! Less than .0015 across in every direction. I got long tube headers, too, as the original exhaust flanges were rotted away. OMG! The car picked up a ton of power! Just amazing. It is just mind boggling how much more power it has with these heads and headers. All the way through the RPM range. You really notice it above 3000 rpm, though. The cam comes alive around there, so these heads really breathe and let it develop so much power above 3K! I wanted to do an LS3 swap, but now, I can wait, as these heads and headers combined to make the Mighty Mouse motor put out big block power.

Watch the prices as they fluctuate wildly, but these can be anywhere from a good deal to an amazing deal. That being said, they won’t be flat, so expect to surface them. For budget builds, you won’t find a better bang for your buck.

Prices are good

Note. These require .100 longer valves even though it says direct replacement. Everything else was great. I took them to my machine shop guy to check flatness and seats and it was solid.

Expect to need the deck machined flush if you buy these. Mine were both .007" warped. So almost 100% out of spec (.004 max). The intake ports aren't a complete match/centered for a FelPro intake gasket (who do you think knows their stuff better?) But I'll be taking up the offset with the oversized holes in the gasket hopefully plus utilize some RTV. These may also potentially need a valve job, time will tell. The initial lapping held alcohol with no visible leaks though I did not let it sit overnight. These heads get 3 stars b/c of the price, you can get the machine work done and build your own valve train to match your application. And these heads will still be probably half the price of the cheapest fully assembled aluminum heads. Expect to have to get aligning spring shims based on your own spring choice. Plus you will have to get +.100" length valves for an accurate spring assembled height. The push rod holes are nowhere, and I mean nowhere, close to being centered on the pushrod but don't rub so maybe we will go with lightening weight. These heads look fantastic out of the box, but you should check and verify deck flatness. You are getting what you pay for: Chinese quality aluminum cast heads; cheap, not perfect, needs some work to be great. Never get these pre assembled like you find sometimes, use quality valve train components, you'll be glad you did. And even with all that, you're still ahead when it comes to cost vs a high quality aluminum head already assembled : $1200+ for an individual head. Overall 3 stars... for now until I get the engine running.

Nice product only miss Moreau info for valve diamèter

As advertised. Good quality castings and lapping valves went well too. Good bang for the buck!

good valve job.Casting good after porting polishing.Needs special stagered rocker arms .150 offset..Needs adjustable guide plates with welding and modifications.All and all needs attention i think tey are good but didnt get them milled down yet. good heads so far.