Double-Hump Comeback

[69VN]

Yea or nay?

http://www.chevyhardcore.com/tech-st...elie-castings/

[NorCam]

Yes sir.

I have my date coded set of 186 heads stored off to the side and the new 302 build already has a set of these aluminum heads on it (painted Chevy orange of course). I was lined up for a pair since news of them coming out last year and got them this past October. I've already run them on the engine and I like them!

A lot!

[marxjunk]

cool..

[Scott69Z]

Were you able to run stock head bolts with them? Is your bottom end a 302? Any dyno numbers on them? I’m very interested in building an engine for my Z using these heads.

Scott

[NorCam]

I used ARP bolts but would think you could run stock bolts. Ed at Trick Flow would be able to answer that for you I'm sure.

Stock 302 bottom end. I didn't dyno but it's been proven these heads flow circles around a fully ported set of 186 iron heads. The intake runners alone are way bigger than stock, and the 60cc chambers are a modern design with excellent port design and flow. There is room for someone who knows what they are doing to get a bit more out of them but these are supposed to be just as good as Trick Flows fast as cast 195cc heads in terms of numbers. That should be an easy 50hp gain in that area.

[Scott69Z]

Wow thanks for the info. I read your day 2 thread and I am really digging your build. Can’t wait to see it finished.

Scott

[BCreekDave]

Assume then with the small heart shaped chambers that they are not bolt ons to a stock 11:1 302 or LT-1 style piston prepped short block. In other words, flat tops required.

[NorCam]

Originally Posted by BCreekDave

Assume then with the small heart shaped chambers that they are not bolt ons to a stock 11:1 302 or LT-1 style piston prepped short block. In other words, flat tops required.

These are forged 302 Speed Pro pistons that were milled down for 11:1 compression and fit fine with these heads. With the current 12-673-4 cam, the piston to valve clearance was Int .190 and Exh .180 with no issue fitting domed pistons. Likely a safe fit with up to .600 lift and would think they'll work fine with stock pistons and stock cam specs as well? With the taller rails they'll also accommodate stock z/28 finned valves covers over roller rockers.

Of course with that being said, I would always suggest every different setup is mocked up and clearance'd properly before being run as no two builds are typically the same. Kinda goes w/o saying right.


Speed Pro L2210F being milled from 12.5 to 11.1 dome


Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet


Checking piston fit


Piston to valve clearance


Degreeing in of the cam


Bolted down with ARP hardware


Topped with a day two look but will fit stock top end.