Hi everyone, I’m a new guy on the forum, living in Norway… about 62 miles from Oslo… My car, since 1987 is -69 Charger R/T SE. It has standing still about 9-10 years now… lost the spark -00 so to say… But now is time to hit the road again…

The engine is .030 over -72 440 with -70 six pack, Forged crank, six pack rods, KB pistons nr 7025P30 with dome, stock 906 heads with 3 angle valve job and hardened seats, compression ratio is 10.3:1, modified Hemi style ½ “oil pick up + high volume oil pump, Erson solid roller 286/286 (246/246 at .050 lift) .555 lift, Comp Cams steel rockers and shafts. MSD AL 6, Hooker headers + 3" exhaust all the way with Apple mufflers.
Light modified 727 and 3000 stall speed converter, 8 ¾ sure grip 3.23:1.

I built the engine back -94… and it’s still fine condition and that six pack on the top of the engine… It’s just screaming… you know B-)

I have bought the Indy-H1- SRAS heads with 75 cc closed cbr… and my question is, can I use those old KB pistons with dome… or do I have to swap to flat top ones. Anyone you guys… experience with this…?
I was in Indy site and there they said that dome piston is no problem… but is that true…?

 

Welcome to the forum! Well since you already have the heads,might as well throw one on and check for piston to valve clearance with some modeling clay. Turn the crank over very slowly a couple of times and check the thickness of the clay.You can use a different thickness head gasket to get the clearance/compression ratio you want.

good luck,john

 

Hi John Van, and thanks for quick response. Yeah I know that method, but I like to just drive now when it’s summer here in Norway… I thought to take a part engine when winter is coming. And I thought maybe someone has experience with those heads and pistons with dome.
My compression ratio is 10.3:1 with 906 stock heads witch is open cbr and regular head gasket… (Don’t remember how thick gaskets are) And Indy has closed cbr on 75cc … so maybe compression ratio is coming an issue here… We have just lousy 98 octane gas here in Norway… and it is pretty much expensive too.. :-/ 10.09 $ per gallon…

 

I would blow it apart and put some KB flat tops in it....google compression ratio calculator and figure out changing just the heads may kill you on the compression ratio...here's a link to the one I always use...

http://www.csgnetwork.com/compcalc.html

 

Sorry 69, I would just contact Indy, and ask them the do's-and-dont's. Ask what they ran for pistons. I would NEVER run new pistons, with a new head, or even new valvetrain, without doing a clay-test for the valves! Took the parts guys advice 20 years ago, and put the valves through the pistons! Never forgot that lesson..."Trust, But Verify!"

 

-69 RT,
Are these the quench type KB pistons? If so, I am currently setting up a motor with them. (http://webpages.charter.net/beckracing/page41.htm) I have 906 heads, seems what they are designed for. I had a concern with the cam as well. I started with a MP purple .509 and it was close, too close (.60) so now I am working with a CompCam .470

B1 heads are out of my budget, so I am not sure on those clearences. But like I said, with 906 heads, standard Felpro gaskets, standard rockers - Too close.

Hope this helps