engine builders help ----406 rebuild

[leafsovrbrs]

dart block 18* top end new eagle 4340 crank 350m 6in rods new ferrer ss valves new erson offset lifters,td 1.5 1.6 rockers---ran on dyno 20 min with 30# breakin oil 650hp cranged oil to 20-50bradpenn installed in mod went racing 6laps in heat started popping pulled in----- 3&5 cyln, were cooler than others- pulled valve covers #5 ex rocker lock nut was lying in head #3 ex lock was lose tore down #3 &#5 exaust valves were bent 3&5 lifters were galled in block my eng guy says he will cover the fix but we were wondering what caused problem he says he is sure the lock nuts were tight
-- any help would be appr thanks for your time

[perfconn]

If it is an SHP block,galling lifters is a common problem.

[a25rjr]

If it is an SHP block,galling lifters is a common problem.

Whats the fix?

[perfconn]

The problem is that Dart put the oil galleys lower in the block than a regular block.Combine this with using high lobe lift cams and small ratio rockers,you end up with the oil band on the lifter rising high enough to shut off the oil supply.You can confirm this by taking an oil galley plug out and turn the engine over until the lifter is at maximum lift.When you look through the oil galley hole you will see that the oil band on the lifter is above the oil galley.
The fix is to hone the lifter bores and use a smaller lift lobe and more rocker if you want the same lift.Large cam cores like 1.948 & 50 mm only make the problem worse.

[brad hibbard]

GREAT INFO perfconn,
I don't personally work on anything except crate engines but have been asked about similar failures with the Dart stuff and I had no answer
and this actually may really help 1 of my guys in the shop who recently purchased an engine for a super stock car that has a Dart block and solid lift cam---he is thinking of making it a roller engine ---I will certainly give him the heads up

thank you

Brad

https://www.race-1.com

[perfconn]

Brad,
I had this problem and could find no help.Changed brands of oil,still galled.Put in bronze bushings in lifter bores,still galled.After much hair pulling out we finally figured it out.We had another engine with .381 lobe lift and 1.90 rockers that had no problem.That gave us the first clue what was going on.

[leafsovrbrs]

thanks very much perfconn for the info

i miked both lifters, the comps that came out of eng before rebuild and the new erson($730.) the ersons were about .001 bigger. and were shorter with a different type of oil band-we have run this eng on & off for 6yr with no problems with galling, ill go back to the comps or hone lifter bore out to fit the ersons--what would you sugest for lifter to bore clearance--- thanks perfconn for the help.leafs ovr bars

[perfconn]

.0015-.0018 should work if everything else is OK.

[leafsovrbrs]

perfconn thanks agin

engine is goeing back to gather but missing one valve, ferrea says it will be 2 wks do you think we could mix brands? the ferrea #f1152p 11/32 stem-5.300 long.1.625 head sorry to keep bothering you but dont want to wait two wks mick

[perfconn]

As long as they are the same length,stem diameter and head diameter the motor doesn't know what brand they are.

[HINKSON AUTO]

The problem is that Dart put the oil galleys lower in the block than a regular block.Combine this with using high lobe lift cams and small ratio rockers,you end up with the oil band on the lifter rising high enough to shut off the oil supply.You can confirm this by taking an oil galley plug out and turn the engine over until the lifter is at maximum lift.When you look through the oil galley hole you will see that the oil band on the lifter is above the oil galley. The fix is to hone the lifter bores and use a smaller lift lobe and more rocker if you want the same lift.Large cam cores like 1.948 & 50 mm only make the problem worse.

Terry Whether you have a .300 lobe lift cam or a .500 lobe lift cam at max lift the lifter will be the same height in the bore !!!!!!!!!!!!!!!! If what you were talking about was true the lobe would be higher the the journal of the cam and you would not be able to get the can in the block LMAO Put a straight edge any roller or flat tappet cam that does not have a reduced base circle cam, Most cams when they are ground the lobes are appox .010 shorter the the journals so you can get the cam in with out damaging the lobes. When you have higher lobe lift cams the base circle get smaller !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Cam lift revolves around base circle size, Smaller base circle more lift larger base circle less lift. Formula for base circle size is lobe lift X2 minus journal diameter. Just so you know I have checked out lifter galley locations before and the Dart SHP and SHP Pro and the Little-M blocks the galley holes are all in the same locations.

[HINKSON AUTO]

GREAT INFO perfconn, I don't personally work on anything except crate engines but have been asked about similar failures with the Dart stuff and I had no answer and this actually may really help 1 of my guys in the shop who recently purchased an engine for a super stock car that has a Dart block and solid lift cam---he is thinking of making it a roller engine ---I will certainly give him the heads up thank you Brad www.race-1.com

Brad I have sold over 250 SHP blocks and the early blocks did have tight lifter bores as I had to hone all the early blocks and never had a problem to date, But when those blocks first came out I did get calls about flat tappet lifter sticking in the bores. I don't let any block out of the shop with out having lifters in hand the set bore clearance. The fix is go to .875 lifter or bush back to standard. Don't listen to the bull(not a nice word)(not a nice word)(not a nice word)(not a nice word) about lifters being to high in the block LOL