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Another 440 Source head question

Rebel426

Rebel426

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I know the Source heads need a thorough going through to check everything. I’ve always heard there are issues with the valve hardware, especially the 7 degree locks. Will the Source springs hold up on a cam with .503” lift or are they too suspect for that mild of a cam?
 
Rebel426 said:
I know the Source heads need a thorough going through to check everything. I’ve always heard there are issues with the valve hardware, especially the 7 degree locks. Will the Source springs hold up on a cam with .503” lift or are they too suspect for that mild of a cam?
Click to expand...
I learned a long time ago that even the top name brand out of the box heads should be checked out at a machine shop. I think the 506-510 or whatever they recommend has to due with the springs. I am running stealth heads and have no complaints thus far.
 
My general rule of thumb is above 0.525", use a 10 degree lock/retainer, and 7 degree lock/retainer below that. Also, what is your intended usage? If it is going to be driven hard, it wouldn't be a bad upgrade for a few more dollars.

Yes, even with new heads that I put on, or customers bring in to check, it is advised to have the valve sealing checked. The heads have the seats cut, and then just populated with production valves. Every now and then, a bad mismatch will affect valve sealing. With the last 3 sets of Edelbrock heads, I had to touch up the valve (made it worse), and recut the seat which was way off. EVERY new valve I use gets the face touched the valve grinder, and better than 90% needed to be trued up.
 
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Same as above. Went thru my Stealth heads. Change the locks and retainers to 10*
Cleaned up the valves and seats as the margin was very thin.My head guy liked the springs that were on them better than the Crane springs that I bought to replace them. This was after checking them for height and pressure over the nose along with coil bind.
 
Ok guys. Maybe I didn’t state my question clearly enough. I know the Stealth heads have to be gone through. That’s a no brainer. I know the locks can be a problem. I’m asking are the springs they come with good enough to use with a cam that has 500 lift or do I need to replace them as well. Source says they are but I’m asking for a real world opinion on that.
 
The 10 degree lock theory is changing. You would be surprised what stuff has gone back to 7 degree. More about the quality and groove shape.
Doug
 
Hard to explain sort-of. Yes they can handle a 500 lift cam.
The hard to explain is are they good for 5000 rpm ? 5500 ? 6000 ? Yes, but will they handle 6800 rpm or more ? It will take the whole combination of your build and the intended use to put it into perspective.
 
I have a 509 lift cam. I found pieces of seven degree retainers broken off during a routine check. Replaced them with the ten degree.
 
dvw said:
The 10 degree lock theory is changing. You would be surprised what stuff has gone back to 7 degree. More about the quality and groove shape.
Doug
Click to expand...
Just had a customer lose a valve and put a hole thru an LS3/7 block because of a 7 degree lock/retainer... In a word, moly or tool steel retainers and machined locks instead of stamped is a step in the right direction, but I still say 10 degrees is cheap insurance for my customers.
 
Geez.... just answer the question maybe ?
We've used/installed lots of the stock Source V/Springs on our Engines, and we haven't heard/had any negative feedback of problems with the Source V/Springs at right around .500" Lift..... like for example on the Comp Cams XE284H stick.
Keep in mind though.... we typically re-do the V/Seat Angles/widths to our better Flowing setup, which raises the V/Spring installed height slightly.... but as long as we're still 120# closed V/Spring pressure we're happy and 'good to go'

As mentioned, the change to 10* 741-16 Comp Retainers/611-16 Locks is a no-brainer..... but we've re-used the Source V/Springs no problems, and keep in mind some of our 440/Hyd Flat Tappet XE284H/Ported Stealth Head builds have Engine Dyno'd right to 545 HP/ 562 Ft/Lns on pump gas.
When 'painted' that is one helluva "sleeper" Engine.
 
Speaking from personal experience. At the time 440source said their springs would handle up to .550 lift and my cam at the time was a .533 lift, so should be good right? WRONG! Broke a valve spring driving one day and luckily it just caused a small miss fire and no major damage. I called 440source out on this over the phone and the guy told me they are only rated for .500 lift. Which was total BS because I took my time to make sure every little detail was covered during my build. So I suspect they had issues with the ".550" lift and just changed the web site to ".500" lift to cover their asses.

If I did it all over again, I would still go with the source heads but I'd plan on changing the springs and lock/retainers. I ended up going with a 7 degree lock and springs from Crower(Tech guy set me up with these specs) since they were the only company I could find with the correct seat pressure and height I needed.
 
Challenger340 said:
Geez.... just answer the question maybe ?
We've used/installed lots of the stock Source V/Springs on our Engines, and we haven't heard/had any negative feedback of problems with the Source V/Springs at right around .500" Lift..... like for example on the Comp Cams XE284H stick.
Keep in mind though.... we typically re-do the V/Seat Angles/widths to our better Flowing setup, which raises the V/Spring installed height slightly.... but as long as we're still 120# closed V/Spring pressure we're happy and 'good to go'

As mentioned, the change to 10* 741-16 Comp Retainers/611-16 Locks is a no-brainer..... but we've re-used the Source V/Springs no problems, and keep in mind some of our 440/Hyd Flat Tappet XE284H/Ported Stealth Head builds have Engine Dyno'd right to 545 HP/ 562 Ft/Lns on pump gas.
When 'painted' that is one helluva "sleeper" Engine.
Click to expand...

Thanks. That's really what I was trying to find out. I wouldn't trust them at .550". I'm running a Voodoo 703 Advertised Duration 268/276, Lift .494/.513 and using 10 degree locks. It's a 60 over 383 and I don't plan on winding the crap out of it, definitely keeping things under 6,500.
 
I have run stock style 7* hardened locks and retainers at 7000 RPM 585 lift for extended periods. Worked fine. But for big cams & high RPM you want the 10* locks & maybe titanium retainers.
 
Rebel426 said:
Thanks. That's really what I was trying to find out. I wouldn't trust them at .550". I'm running a Voodoo 703 Advertised Duration 268/276, Lift .494/.513 and using 10 degree locks. It's a 60 over 383 and I don't plan on winding the crap out of it, definitely keeping things under 6,500.
Click to expand...

We've Dyno'd that Cam extensively, forget the 'advertised' rpm range, it's all done by 5,500 rpm no matter the Stealth Heads/Intake makes no difference.... it's in the Cam and IMO, a complete waste of time revv'ing higher to go slower.

Which this is maybe a little off topic comment......
but just say'in
it's amazing how many people seem to subconsciously at least somewhat 'shop' or select a Cam based on it's advertised/published rpm range put out by the manufacturer ? And then believe erroneously that the Cam should rpm to that "advertised" upper number ?
FALSE !
Many Cams for example advertise a 3,000 to 6,500 rpm range..... all that means is that is "theory" and assuming everything within an absolutely perfect Engine dynamics scenario the Lobe profiles should remain "stable" to that upper rpm if the required V/Spring pressures etc are present.
NOWHERE does it mean that is where the particular Cam will make power to that upper number... let be BEST power.

I'm done.... morale of the story for anyone reading, do not select Cams based on 'published' rpm ranges.... let be try and Rev them there once installed.... which many tend to do subconsciously, and then in the Car anyway.
 
So what does it take to get a cam to run in the upper advertised RPM range?

Let us consider the Comp XE285HL and its advertised range of 2,500-6,200 rpm running in a pump gas 8.9:1 +.030 440. There were 80 dyno runs on this engine during the testing period. We'll just list a few to show what Challenger340 was saying.

1st ever test during the 80 test session. Ported 346 iron heads and XE285HL cam 1/16 turn preload....
...489 HP @ 5,400 rpm
...474 HP @ 5,600 rpm
More porting and a few other small changes like carbs and manifolds....
...519 HP @ 5,400 rpm
...473 HP @ 5,700 rpm
Same as above but change to solid lifters on the XE285HL....
...517 HP @ 5,500 rpm
...508 HP @ 5,700 rpm
...498 HP @ 6,100 rpm.......and now we are beginning to reach the advertised upper rpm
More porting on the 346 iron heads....
...540 HP @ 5,500 rpm
...531 HP @ 5,700 rpm
...523 HP @ 5,900 rpm

So what happens if we remove the 346 iron heads and replace them with some ported Indy EZ heads @ 10.4:1 compression?
...540 HP @ 5,300 rpm
...552 HP @ 5,700 rpm
...595 HP @ 6,500 rpm.....and we have exceeded the advertised upper rpm limit. All with the same XE285HL cam.

None of these were perfect combinations, and others my have exceeded these performance levels, but they do illustrate how the engine combination will effect camshaft rpm ranges.
 
Challenger340 said:
We've Dyno'd that Cam extensively, forget the 'advertised' rpm range, it's all done by 5,500 rpm no matter the Stealth Heads/Intake makes no difference.... it's in the Cam and IMO, a complete waste of time revv'ing higher to go slower.

Which this is maybe a little off topic comment......
but just say'in
it's amazing how many people seem to subconsciously at least somewhat 'shop' or select a Cam based on it's advertised/published rpm range put out by the manufacturer ? And then believe erroneously that the Cam should rpm to that "advertised" upper number ?
FALSE !
Many Cams for example advertise a 3,000 to 6,500 rpm range..... all that means is that is "theory" and assuming everything within an absolutely perfect Engine dynamics scenario the Lobe profiles should remain "stable" to that upper rpm if the required V/Spring pressures etc are present.
NOWHERE does it mean that is where the particular Cam will make power to that upper number... let be BEST power.

I'm done.... morale of the story for anyone reading, do not select Cams based on 'published' rpm ranges.... let be try and Rev them there once installed.... which many tend to do subconsciously, and then in the Car anyway.
Click to expand...
I pay attention to the advertised RPM range but that's not the deciding factor by a long shot. In this case, I went with something that had the lift and duration in the range I wanted. I don't care to push a big block past 6,000 on the street. It's just not needed and the kick in the pants feeling comes from the torque anyway. I wanted to see what the experience was with the springs from Source heads. What Source advertises says they should work with the cam and I have them on the shelf. I didn't want to give Lunati $200 for a set of springs if I already had a new set that would work fine. The cam is going in a 383 that's bored 30 over with mildly ported 915 heads. The Road Runner is more of a "day two" restoration so I'm using a vintage DP4B on it. Again, I know there are a lot of options to make more power than what I'm using, but a lot of these parts are things I already have and I think it should make for a neat car. I'm curious as to what your dyno results were with this cam though.
 
Rebel426 said:
I don't care to push a big block past 6,000 on the street. It's just not needed
Click to expand...
I agree to both quotes.
Rebel426 said:
kick in the pants feeling comes from the torque
Click to expand...
:thumbsup:
I did my best to say that the 440 Source springs were good for you to use in post #4. I guess what I was thinking did not show up in what I was typing.I forgot to say that I was using a .490 lift Comp prototype cam.That was when they were going to market the Thumper cam line.
 
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