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Valve Springs

Has anyone changed their valve springs? How long did it take?

I want to go to a stiffer spring. Apparently, the springs are the Achilles heal for people that are going higher than 7500 rpm. In my races last weekend I was getting a back fire when down shifting into tight (slow) turns. I’m really paranoid of losing a valve into the cylinder head.

Any thoughts?
 
I think upgrading the valve springs is a good idea. Another member had a valve spring break and trashed his motor. He thinks it happened on a hard downshift where he over revved the engine by a fair margin. The rev limiter only works with the throttle. ;)
 

steveespo

Lord knows I'm a Voodoo Child
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Roush Yates make a great set of valve springs for these engines. They're expensive but good to sustained 8200 running. There are special tools to remove the spring retainers available and you have to follow the exact procedures for removing and replacing the cams and phasers. I would say remove the engine or at least drop the K member so you have clear access. This is an 8 out of 10 difficulty. Need new cam bolts and gasket set for the cam covers too.
Others may have different opinion but from what I've read its not easy.
Steve
 
steveespo said:
Roush Yates make a great set of valve springs for these engines. They're expensive but good to sustained 8200 running. There are special tools to remove the spring retainers available and you have to follow the exact procedures for removing and replacing the cams and phasers. I would say remove the engine or at least drop the K member so you have clear access. This is an 8 out of 10 difficulty. Need new cam bolts and gasket set for the cam covers too.
Others may have different opinion but from what I've read its not easy.
Steve

Bummer! I have read the same things. Some people have said, with the right tools, you can do it with the cams in. I just don't see how you get under the cam to get to the keepers.

[youtube]https://www.youtube.com/watch?v=-uQi0oJeYHM[/youtube]
 
WinterSucks said:
Pretty sure the answer will be Boss 302S springs. Not sure how long it would take, I have never worked on an engine larger than a Saito 150...

I have the S springs, but there has been a few issues with those, so I got some for the R which are a little stiffer.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
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Nice valve spring compression tool, I noticed the demo video had the cylinder head on the bench. I wonder if you could use compressed air through the spark plug hole to hold the valve up, with the cylinder(s) at TDC while you replace the springs?

If possible to use compressed air, and keeping the cams in place you might be able to replace the valve springs and not remove or drop the engine?

Hopefully you don't have to bench the cylinder head for this. It would be interesting to see the Ford labor operations to see how much time they pay to do this job.

Just a thought,
302 Hi Pro
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
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ArizonaBOSS said:
The cams are directly above the valvesprings so I don't see how that's going to work without at least getting the cams out :(

I agree with you, but that is what the video said, and I found that confusing. (Note: That is why I started with "If".) You still have to remove the cam journal caps to install the base of the tool. Now I haven't had mine apart, so I'm not sure why the instruction video said that, unless someone was just replacing the keepers?

But even so, I would think it is possible to do it without dropping the engine.
2HP
 

steveespo

Lord knows I'm a Voodoo Child
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The cams act on finger followers which are mini rocker arms with a hydraulic lash adjuster on one end and the valve tip on the other. There is no way to remove a spring or retainer without pulling the cams. As far as working on the engine in the car, if you have leaned over the fender long enough your back will give out and your precision will go right out the window. Not to mention keeping debris and grit out of the heads. If you pull or drop the K member I think an experienced DIY mechanic with the right tools can get the job done.
Steve
 

JScheier

Too Hot for the Boss!
I hate to say it, but in the old days, we used to change springs on the 32V cobras without pulling the cams.

Tool of choice was a large prybar to pop the follower in / out. Wasn't pretty, but it worked. Compressed air into the cylinder kept the valve from dropping.

...and yes, back pain was a constant :)
 

Grant 302

basic and well known psychic
ArizonaBOSS said:
I'd rather go with the Freedom Racing compressor shown earlier, despite the more expensive price.

Absolutely agree! I wouldn't try an on-board cams-in spring swap myself. I've always pulled engines to do the work.

I'm just surprised there's no way to make a tool for our engines like the 2V compressor by OTC:
1328053341824-1886066730.jpeg
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
437
Southeast
AZBoss:

From some of your post I'm getting the impression your getting ready to do some major engine work. Are you getting ready to do a rebuild? Hope all is well.

302 HP
 

ArizonaBOSS

Because racecar.
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302 Hi Pro said:
AZBoss:

From some of your post I'm getting the impression your getting ready to do some major engine work. Are you getting ready to do a rebuild? Hope all is well.

302 HP

Yeah. Nothing systemic to worry about, though. Just made some poor decisions regarding fuel and fuel additives. Heads fine but rings toast on #8, others may be on the way out. Car will be back and stronger than ever in a couple months.
 

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