JB weld, flex seal or full rebuild ?

-
Is the return worth the added expense? I will have to learn some more about this.. I think I want it but not sure why I do.. LOL
 
Is the return worth the added expense? I will have to learn some more about this.. I think I want it but not sure why I do.. LOL
For a street application - dont waste your money. Research this forum regarding problems with roller cams in SBM's.
 
Is the return worth the added expense? I will have to learn some more about this.. I think I want it but not sure why I do.. LOL
After the switch...I had a hard time trying to talk myself into using a flat tappet again in my other motor..still on the fence. Its quite, like a sewing machine in fact..throttle response is the stuff dreams are made of..lol
I think it's worth it street wise if you use a tamer one, track wise if you go all out... but aside and more general... cam it for the heads you have have or you'll be throwing it out the window. Everything has its application. If it makes more power and can hang in there...why would you go back.
If you start from scratch... how much does a solid flat tappet and all hardware to go with it run? Not too far apart.
 
Yep.
Springs, switch to 10 degree locks n retainers if solid roller. Price accordingly..180-300
Cam-300ish bucks
Roller lifters 300-1,000+
Crane coated steel gear for billet core 90.00

It can add up. I went through herbert cams and got a nice setup for less.

The Herbert stuff looks really good on paper but they scare me. I went through THREE hydraulic flat tappets from them a few years ago and not one of them measured to the specs on the cam card. Not even close. Each one they took back, inspected and agreed with me. The third return, I asked for a refund. It was not a small difference, either.
 
Looking at this kit from Summit..
My bore is currently 4.0475 at the top of the cylinder, I don't have a way to measure any deeper into the bores. With the minimal run time would I be able to use some Icon 745-40 pistons or should I look bore it out to 60 over?

Ruled out the roller cam...

Scat Engine Rotating Assemblies 1-48035
 
Depends on how badly the bores are scored and what the requirement in clearance is between the Icon pistons and your present bore. IIRC, Icons are 2618 alloy forgings so they can run tighter than 4032 alloy. But usually the difference between hypereutectic and forgings of the same over size is significant enough to require re honing. So really, you’ll have to dismantle it and get it measured to know for sure.
 
The Herbert stuff looks really good on paper but they scare me. I went through THREE hydraulic flat tappets from them a few years ago and not one of them measured to the specs on the cam card. Not even close. Each one they took back, inspected and agreed with me. The third return, I asked for a refund. It was not a small difference, either.
Ouch X 3
Lesson learned the hard way.
 
Was the block sonic checked when you built it the first time? I would get that checked first if it hasn’t already been done if it looks like it’s going to need bigger than a .040 over piston. It’s dependent on year, but sometimes going much past .040 on certain 360 blocks can make things thinner than they need to be. If it’s a ‘71-‘73 360, though, the odds would be more in your favor.
 
The Herbert stuff looks really good on paper but they scare me. I went through THREE hydraulic flat tappets from them a few years ago and not one of them measured to the specs on the cam card. Not even close. Each one they took back, inspected and agreed with me. The third return, I asked for a refund. It was not a small difference, either.
To my knowledge there is 1 guy that grinds for a few different companies/brands and he always grinds them a little off, be it cause the specs were **** and wouldn't last or who knows. Engle does their own, but I think bullet uses him , the one guy, too.
I knew his name once upon a time...
I have gotten cams suspect on the phone and when the cam showed up the card was not exactly what was spoken about on the phone. Sometimes what we want and what's actually going to work are 2 completely different things.
 
Wow. Some great knowledge her. A good read, even i got most of it. as far as the young man goes,
He owned his error.
Very difficult to admit something like that, unless he was bragging.
I know a lad just like that. Hard launching daddy’s new duramax dually.thinks its funny.
 
To my knowledge there is 1 guy that grinds for a few different companies/brands and he always grinds them a little off, be it cause the specs were **** and wouldn't last or who knows. Engle does their own, but I think bullet uses him , the one guy, too.
I knew his name once upon a time...
I have gotten cams suspect on the phone and when the cam showed up the card was not exactly what was spoken about on the phone. Sometimes what we want and what's actually going to work are 2 completely different things.

It was one of their off the shelf grinds.
 
It was one of their off the shelf grinds.
Then let me share you a bit of info...

I dont grind cams, i do some about tooling and machining... so i was told as the wheel wears... the set profile on the machine will be slightly off...your events will be be off and id assume on both ends equal. Open close.
That said... i have NEVER been happy with every product a company makes, NEVER.
I have had to pick and choose, mix match brands to get where i'm going with it.
Needless to say...I'm disappointed they didn't advertise accurately in your case.

Biggest inaccuracies are with valve springs, not a one is dead nuts what its advertised at a given lift, be it 5 lbs or 20.
 
Depends on how badly the bores are scored and what the requirement in clearance is between the Icon pistons and your present bore. IIRC, Icons are 2618 alloy forgings so they can run tighter than 4032 alloy. But usually the difference between hypereutectic and forgings of the same over size is significant enough to require re honing. So really, you’ll have to dismantle it and get it measured to know for sure.

I dont know how accurate his measuring tools are...but that 4.0475...comes out to..
.0075 ...so .00372ish on each side, right?
Thats fine, unless the clearance is built into the piston..lol...fhr or hyper or any piston he wants to run.
 
Agreed, and according to UEM/Icon, the 2618 has a higher rate of expansion, requiring more clearance. I had managed to transpose that in memory somewhere along the way. Their site has a chart showing allowable clearance of .035 to .070 for a three and a half inch to a four and one tenth inch bore, depending on exact usage, and a ring gap size to bore factor. Of course there is a lengthy disclaimer about needing to give careful consideration to what the individual demand of the application before deciding where to set final clearances. To me, that reads as a "between the lines" suggestion to set pistons and ring gap more on the loose side of spec than the tight side.
 
Last edited:
I added gap to my KB pistons on the Top and second ring. I don't remember what I increased to. I read an article about adding top ring gap and a little more gap on second ring. The second ring wasn't as much as the top ring. This was an engine builder who claimed there was no issues with compression and blow by . I will try and find the article. I have not had any issues.
 
I would disregard my 2nd ring gap statement but I found this may have been why I did mine.
(Quoted) The larger second gap nowadays is not a fad. There are people with a lot more knowledge of the subject (and oem manufacturers also). Engine masters also. It's trickled down from the high eng race teams. It's to aid in controlling/preventing top ring flutter/unseating from pressure built up between the top and second ring.
 
I am not planning on going back to a hyper-eutectic piston, I am looking at the forged icon, ross etc.. I am away from home as usual, but I plan on taking the block to a machine shop in the Dallas area for inspection and evaluation. Hopefully there is no damage to the block, and the story will have a happy ending with modern parts and modern ring gaps!
 
-
Back
Top