552 p-51

Yes sir the block is stock

A lot of people seem to think that when valve float or bounce happens, the engine somehow just stops RPMing and that just isn't true.

NON valve control can happen anywhere in the RPM range IF the valve train frequencies all happen to line-up unfavorably at the same time and the engine can actually run THROUGH that range.
Also, valve float or bounce, (as most people visualize it), can happen gradually and the engine can rev even 1,000 RPM past where it begins to happen.

So would the valve springs play a major part in valve float. Such as spring pressure

larry552 wrote:So would the valve springs play a major part in valve float. Such as spring pressure

Certainly ... however, it is NOT all about spring pressure.
More spring pressure can actually CAUSE valve float to happen sooner if that extra pressure is responsible for more flex happening in the rest of the valve train.

That's great info i am putting my p51 back together with titanium retainers with new springs with about 275 on the seat @2.00 install height. My last locks and retainers were pretty ugly when my head man tore my heads apart

I had valve float on an engine of mine several years ago and uped the spring pressure and it got worse, Push rods were the problem, Lem called it and I changed push rods and dropped the springs back to where they were and the problem went away.

Everything from the lifter to the valve is suspect..............

Ok sir thanks

larry552 wrote:Yes sir the block is stock

I didn't read.all the pages tonight.but what size bors is that?
and.do.you.have hard block in it.? Up to the.water.pump holes?
thanks

It will 4.420 when I get the machine work done and from what john kasse told me 0.60 would be the max before you start having to fill to the water jackets. I might even try and go 0.080 and see if i can get away with it

larry552 wrote:It will 4.420 when I get the machine work done and from what john kasse told me 0.60 would be the max before you start having to fill to the water jackets. I might even try and go 0.080 and see if i can get away with it

my D1 block is. 060 over right now.that's 4.420 I know it wont take A. 080 oversize.it needs.at least another. .040 to. 050 more.to clean it up.that's. .020 to. 025 more per side. Looks like that what it will take
Might bring it to my M/Shop tell.them to. Make.a.pass.on the worst.hole.it see if. 080 will do it. And sonic check it. Then if okay . See.about a 4.470 bore and hard block. This will be a racecar only. It might see 20 passess and about 2/3 years. Remember 175/250 shot of nitrous. Too. WUT.?

2fox wrote:

larry552 wrote:It will 4.420 when I get the machine work done and from what john kasse told me 0.60 would be the max before you start having to fill to the water jackets. I might even try and go 0.080 and see if i can get away with it

my D1 block is. 060 over right now.that's 4.420 I know it wont take A. 080 oversize.it needs.at least another. .040 to. 050 more.to clean it up.that's. .020 to. 025 more per side. Looks like that what it will take
Might bring it to my M/Shop tell.them to. Make.a.pass.on the worst.hole.it see if. 080 will do it. And sonic check it. Then if okay . See.about a 4.470 bore and hard block. This will be a racecar only. It might see 20 passess and about 2/3 years. Remember 175/250 shot of nitrous. Too. WUT.?

I actually heard that some stock block can be bored to a 4.500 bore. But what year block will take that much overbore?

dfree383 wrote:

2fox wrote:

2fox wrote:

larry552 wrote:It will 4.420 when I get the machine work done and from what john kasse told me 0.60 would be the max before you start having to fill to the water jackets. I might even try and go 0.080 and see if i can get away with it

my D1 block is. 060 over right now.that's 4.420 I know it wont take A. 080 oversize.it needs.at least another. .040 to. 050 more.to clean it up.that's. .020 to. 025 more per side. Looks like that what it will take
Might bring it to my M/Shop tell.them to. Make.a.pass.on the worst.hole.it see if. 080 will do it. And sonic check it. Then if okay . See.about a 4.470 bore and hard block. This will be a racecar only. It might see 20 passess and about 2/3 years. Remember 175/250 shot of nitrous. Too. WUT.?

I actually heard that some stock block can be bored to a 4.500 bore. But what year block will take that much overbore?

No specific blocks will go to 4.500, they are very few and far between.

I've see a few Boss 9 block they where useable at 4.500, but thats about it.

thanks maybe that's what it was
the. 060.over. motor. I got needs about another. 050-.060 and it has a sleeve in it so that's ones Junk!

I had a D9TE block that sonic checked good to a 4.5 bore also. They are out there, but there is no specific block that you can look for that will go that far.

2fox wrote: the. 060.over. motor. I got needs about another. 050-.060 and it has a sleeve in it so that's ones Junk!

Its not junk because of the sleeve (If it has been installed correctly) it will be junk after another .050-.060" overbore probably.

schmitty wrote:I had a D9TE block that sonic checked good to a 4.5 bore also. They are out there, but there is no specific block that you can look for that will go that far.

Mark Laczo wrote:

2fox wrote: the. 060.over. motor. I got needs about another. 050-.060 and it has a sleeve in it so that's ones Junk!

Its not junk because of the sleeve (If it has been installed correctly) it will be junk after another .050-.060" overbore probably.

Thanks for.giving me hope. The sleeve I guess was install at Ford its got.a.Fred Jones tag on it built in 1985 its at 4.420 right now.I think it.might need to go as much as 4.470 to get it cleans up

I don't know why they pulled the motor out? Cause the sleeve leaked water in the crankcase or they pulled it to built a bigger BBF and let it sit and got rained.in my guess.buy Lois of it that it got rained.the the Carb cause under it had white crusty stuff when I took the Carb off.the Guy I got it from say to his knowledge that it was STD.bore. maybe he just didn't know cause buy the looks of him he might have been 5 yrs old at that time. But he did tell me that he had a 521 I believe. I will get them both checked out this week. My other block is a C9 STD.bore block.
Thanks.getting knowledge here