Sure! I dont think 650 to 675 would be an issue. Maybe with the spray on top but I dont think I will need much of it to get where I want to be.
I always hear the term spray and pray! LOL
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Sure! I dont think 650 to 675 would be an issue. Maybe with the spray on top but I dont think I will need much of it to get where I want to be.
Depends on the Pistons in it. But you should be able to re cut the reliefs, or have someone do it for you. There are in engine tools available you can use to do it without taking the engine apart. You would have to take your new heads apart, and the cutters look like a valve sorta. They work good for the purpose of what you would possibly need to correct. Adding radial clearance. They don't work that good for cutting existing valve reliefs deeper. Stock 400 blocks are generally living on borrowed time above 600 hp.splitdecision71 wrote: ↑Mon Oct 01, 2018 4:47 pmSo you think I can go from the 2.02/1.6 to the 2.100/1.625 with the 60/40 split and be ok? Man that would be awesome.JoePorting wrote: ↑Mon Oct 01, 2018 3:20 pm Your old pistons will probably work as is. Most piston manufacturers make the valve reliefs extra large to accommodate most aftermarket cylinder heads. Just mock them up and check the clearance with clay.
Thanks for your input sir!Frankshaft wrote: ↑Mon Oct 01, 2018 6:03 pmDepends on the Pistons in it. But you should be able to re cut the reliefs, or have someone do it for you. There are in engine tools available you can use to do it without taking the engine apart. You would have to take your new heads apart, and the cutters look like a valve sorta. They work good for the purpose of what you would possibly need to correct. Adding radial clearance. They don't work that good for cutting existing valve reliefs deeper. Stock 400 blocks are generally living on borrowed time above 600 hp.splitdecision71 wrote: ↑Mon Oct 01, 2018 4:47 pmSo you think I can go from the 2.02/1.6 to the 2.100/1.625 with the 60/40 split and be ok? Man that would be awesome.JoePorting wrote: ↑Mon Oct 01, 2018 3:20 pm Your old pistons will probably work as is. Most piston manufacturers make the valve reliefs extra large to accommodate most aftermarket cylinder heads. Just mock them up and check the clearance with clay.
I am looking at tools to do this myself. What is the math involved or the measurements I will need to get to figure out the proper depth to cut the reliefs? Thanks in advance.
Thanks for your response sir. Fortunately I may have come up with a really nice 434 short block assembly and not have to use the 11x's on the 406.JoePorting wrote: ↑Tue Oct 02, 2018 4:21 pm It's not a depth issue, but radial issue. The intake valve will be off center toward the center of the piston so that is where to look. You'll probably still have around .070" clearance if your pistons are like most pistons.
TBH I haven't either sir. I was told it was for a certain class of dirt track racing which I know nothing about. I could be wrong but thats what I was told.
Thank you!prairiehotrodder wrote: ↑Thu Oct 04, 2018 5:32 pm piston that has been notched with a Lindy Tool for an AFR 227 head which is 60/40 spacing
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Maybe he doesnt want me to know what kind of heads are on it!!!!!!!!
Im sorry sir, I wasnt clear enough on that. Looks like I may end up with the 434 short block that had 18 degree heads and I will be putting the 23 degree Brodix 11x heads on it. Thats what I was trying to say. Sorry about that.JoePorting wrote: ↑Thu Oct 04, 2018 7:01 pm 18 degree heads don't work with 23 degree pistons generally because the valves on an 18 degree head are more in the center of the chamber not to mention the valve angle is different. By that I mean the entire valve centerline is more centered than just the valve spacing. Although you should be able to cut eyebrows in as mentioned before. Check for piston thickness at the eyebrows after cutting.
Maybe that is what it has. I will know more this weekend and Ill get back with you.