Disaster on the dyno

[MOPOWER871]

You wrote they were also ported, so the seat could certainly have been affected during that process.

Also, if we're talking stiffer springs, then they would be putting greater pressure on the seats than the manufacturer intended.

The head porter has been porting heads for 30 + years, is it possible yes IMO unlikely. Intake spring, dual with damper. 200 lbs. seated Ex.508 lbs.open. Int. valve 2.32 Ex. valve 1.94 200 lbs seat pressure does not seam excessive for a solid roller.

 

[Qbrozen]

Edelbrock has been around even longer. Anything is possible, and since it was tampered with, we'll never know the root cause and therefore can't blame edelbrock.

 

[fbs63]

Edelbrock has been around even longer. Anything is possible, and since it was tampered with, we'll never know the root cause and therefore can't blame edelbrock.

 

[fbs63]

200 lbs on the seat is light for a 2.320 valve. Especially for a Hemi. How high did they spin it. Probably was in valve float.

 

[dvw]

Not the first Hemi seat I've seen fall out.
As stated there have been some issues previously.
Doug

 

[Challenger340]

I don't get it ? and I guess I am missing something here ?

7 days ? as in SEVEN DAYS ? on the Dyno ?
to.....
"get" to the 800hp ? because they were "checking" Bearings ? and trying different Cams ? on a Big Inch High Compression Roller HEMI ?

This makes no sense to me whatsoever, and waaay before anyone starts pointing fingers at edelbrock, some other things need addressed, because:
1.) typically someone would want to find "max" power with the FIRST Cam, before moving to the next candidate ? and the First Cam's Dyno data then correlated against the prior Porting's Head Flow data would dictate the decision ?
Nobody I know "tries" different Cams on the Dyno these days unless doing R & D on restricted classes ?
But N/A UN-restricted ? Don't these guys have a Flow Bench and some Computer software ?

2.) Nobody I know dis-assembles an Engine off the Dyno to "check" Bearings .... NEVER heard of it..... unless something/bearing trouble was indicated during an Oil Filter being cut apart and analysed, as is done frequently during/after runs in the Dyno session ?
What I mean is.... just what the F*ck are they looking for in a NON-Blown Fuel/Alky Bearing application ? "Those" may squish a Bearing somewhat(wider)
But on an 800hp deal ? as long as the Filter checks are good...FORGET IT !

3.) Big Inch ?.... High Compression ?.... HEMI ?.... using anything decent in the way of a Roller Cam ?
If I wasn't waaaaaay past 800hp on the first 6 pulls of the FIRST DAY on the Dyno after morning ring seat/break in.... someone best be heading for the DOOR !
Namely MY CUSTOMER !

Big Inch Hemi's using good Heads and Pump Gas (91 Octane) with nice easy Roller Cam Ramps can sail right PAST 900hp by early afternoon on the FIRST DAY !

Loose V/Seats will fall out or "move" during Porting/Seat Cutting.... looooong before they should EVER get assembled or make it to the Dyno.
What KNOCKS a V/Seat out in operation is Valve BOUNCE from a BASHER Roller Rate Cam profiles with insufficient V/Spring pressure !
it's that....
or knock the Head off the 1 pc SS Valve itself as the bounce frequency is concentrated at the narrowest point UP the Valve Stem from the Seat.
In this case looks like the Bounce "frequency" CRACKED the V/Seat first maybe ? then it fell out ?
200# Seat is NOT enough... and heaven forbid probably using 550# rate V/Springs ? yikes !

I call GONG SHOW !
RUN Forrest RUN !

 

[IQ52]

I don't get it ? and I guess I am missing something here ?

7 days ? as in SEVEN DAYS ? on the Dyno ?
to.....
"get" to the 800hp ? because they were "checking" Bearings ? and trying different Cams ? on a Big Inch High Compression Roller HEMI ?

This makes no sense to me whatsoever, and waaay before anyone starts pointing fingers at edelbrock, some other things need addressed, because:
1.) typically someone would want to find "max" power with the FIRST Cam, before moving to the next candidate ? and the First Cam's Dyno data then correlated against the prior Porting's Head Flow data would dictate the decision ?
Nobody I know "tries" different Cams on the Dyno these days unless doing R & D on restricted classes ?
But N/A UN-restricted ? Don't these guys have a Flow Bench and some Computer software ?

2.) Nobody I know dis-assembles an Engine off the Dyno to "check" Bearings .... NEVER heard of it..... unless something/bearing trouble was indicated during an Oil Filter being cut apart and analysed, as is done frequently during/after runs in the Dyno session ?
What I mean is.... just what the F*ck are they looking for in a NON-Blown Fuel/Alky Bearing application ? "Those" may squish a Bearing somewhat(wider)
But on an 800hp deal ? as long as the Filter checks are good...FORGET IT !

3.) Big Inch ?.... High Compression ?.... HEMI ?.... using anything decent in the way of a Roller Cam ?
If I wasn't waaaaaay past 800hp on the first 6 pulls of the FIRST DAY on the Dyno after morning ring seat/break in.... someone best be heading for the DOOR !
Namely MY CUSTOMER !

Big Inch Hemi's using good Heads and Pump Gas (91 Octane) with nice easy Roller Cam Ramps can sail right PAST 900hp by early afternoon on the FIRST DAY !

Loose V/Seats will fall out or "move" during Porting/Seat Cutting.... looooong before they should EVER get assembled or make it to the Dyno.
What KNOCKS a V/Seat out in operation is Valve BOUNCE from a BASHER Roller Rate Cam profiles with insufficient V/Spring pressure !
it's that....
or knock the Head off the 1 pc SS Valve itself as the bounce frequency is concentrated at the narrowest point UP the Valve Stem from the Seat.
In this case looks like the Bounce "frequency" CRACKED the V/Seat first maybe ? then it fell out ?
200# Seat is NOT enough... and heaven forbid probably using 550# rate V/Springs ? yikes !

I call GONG SHOW !
RUN Forrest RUN !

Finally some real reasoning!

And I was told I mix sarcasm and humor into a warm fuzzy ball.

Hah! More than one person has that ability!

 

[moper]

That was a little more "type A" than I might get...lol. At least without some JD in me.

 

[dvw]

No one has stated the application of this engine. Maybe this was an all out to last HP build? Maybe running 0W oil, low oil pressure etc? I'll bet a lot of S/S , Stock, and Comp guys spend days on the dyno with cam tuning.
Doug

 

[IQ52]

No one has stated the application of this engine. Maybe this was an all out to last HP build? Maybe running 0W oil, low oil pressure etc? I'll bet a lot of S/S , Stock, and Comp guys spend days on the dyno with cam tuning.
Doug

This was an all out race motor.They where trying to get it right 7 days because they where pulling bearing to check them and trying different cams.It happened around 800 HP mark.These where out of the box meaning brand new never run, but he had better valves, springs...installed to match the cam profile.
The intake valve seat is suspect because it was cracked in two and not hammered like it being slammed up and down.
bearings looked like the crank was twisting. (scat crank)

The head porter has been porting heads for 30 + years, is it possible yes IMO unlikely. Intake spring, dual with damper. 200 lbs. seated Ex.508 lbs.open. Int. valve 2.32 Ex. valve 1.94 200 lbs seat pressure does not seam excessive for a solid roller.

Something is bad wrong here and I don't see it as the cylinder head.

Big inch? High compression? HEMI? All out race motor? Valve spring pressure for 2.32/1.94 valves, 200# seat, 508# open. Around 800 HP?

My 451 stroker, @ 11.7:1 compression, with ported Edelbrock RPM heads, 2.25/1.81 valves, 220# seat, 750# open, made 19 pulls in 10 hours. 745-787 horsepower on pump gas! In different configurations the little 451 has over 100 pulls at better than 700 HP and even 694 HP with 906 iron heads. It's now in the shop truck @ 580 HP.

Bad Hemi, bad build.

Bad cylinder head? I doubt it.

I agree......Run Forrest! Run!

Oh, and Bob is really right about the low 200# seat pressure. I keep looking at my notes and saying, "Did I really run only 220# on the seat?" When my memory says "270". Oh well.

 

[6PKRTSE]

Something is bad wrong here and I don't see it as the cylinder head.

Big inch? High compression? HEMI? All out race motor? Valve spring pressure for 2.32/1.94 valves, 200# seat, 508# open. Around 800 HP?

My 451 stroker, @ 11.7:1 compression, with ported Edelbrock RPM heads, 2.25/1.81 valves, 220# seat, 750# open, made 19 pulls in 10 hours. 745-787 horsepower on pump gas! In different configurations the little 451 has over 100 pulls at better than 700 HP and even 694 HP with 906 iron heads. It's now in the shop truck @ 580 HP.

Bad Hemi, bad build.

Bad cylinder head? I doubt it.

I agree......Run Forrest! Run!

Oh, and Bob is really right about the low 200# seat pressure. I keep looking at my notes and saying, "Did I really run only 220# on the seat?" When my memory says "270". Oh well.

Sucks to hear. I was a little nervous while dyno'ing my 528" Hemi. Mine made 853 HP & peaked out at 7100 so we shut it down after 7300 after each pull. We made 17 pulls on it altogether with the dual carbs jetting, timing, vacuum pump etc all dial in.

 

[dvw]

Maybe a FAST build? Just saying we don't have all the facts. My friend has had seats come out on a factory built Mopar crate 572 Hemi. Also seem some issues with Gen 3 Hemi. Since I personally didn't take them apart I can't give the true cause. However if the machined area for the seats was too large and there wasn't enough press, especially with an aluminum head it makes sense there could be an issue. If the seats came with the head how many would remove them and measure? Maybe the shop did screw up, maybe not.
Doug

 

[Cranky]

Maybe a FAST build? Just saying we don't have all the facts. My friend has had seats come out on a factory built Mopar crate 572 Hemi. Also seem some issues with Gen 3 Hemi. Since I personally didn't take them apart I can't give the true cause. However if the machined area for the seats was too large and there wasn't enough press, especially with an aluminum head it makes sense there could be an issue. If the seats came with the head how many would remove them and measure? Maybe the shop did screw up, maybe not.
Doug

Since I have no experience with press in seats I'll ask....exactly how would you remove them for measuring and how tight should they be? Also, is there a bonding agent available that could also be used that would take the heat etc. We've used bonding agents at work for a lot of stuff in high heat apps but don't think we had to deal with the heat that a cylinder generates.

 

[HEMI-ITIS]

I have never bought a new set of heads,but did stay in a Holiday inn express,,,,no wait

All joking aside,if the new heads came with the seats installed,the builder would only need to make sure the valves have a good seating area and install the valve springs.Jimmy,that spring pressure is very light for a max effort Hemi.