LT1-LT4 Modifications 1993-97 Gen II Small Block V8

how hard is it to change spring while the heads are still on?

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Old 12-16-2007, 08:40 AM
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Default how hard is it to change spring while the heads are still on?

lt1 heads , spring change i know you need a air adapter to do it but how hard is it . or does anyone know how much it would be to swap them out at a performance shop?

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Old 12-16-2007, 08:51 AM
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You don't need an air adapter, there is another method. The air adapter is best but not totally necessary. Remove the valve cover, take off the rockers, cover the oil drain holes. Use one of those spring remover tools to remove the stock spring, be careful not to drop the locks. The valve seal will hold the valve upright and somewhat high, although it may fall a little bit, don't worry. Take a 5/8 socket and a breaker bar, and slowly turn the motor over until you feel the piston hit the valve. Slowly keep turning the motor over until it pushes the valve up as high as it will go. It WILL raise the valve up high enough to swap on the new spring, you may have to compress it a little further than you would to remove the old one. Once you have the one valve done, you can do the next valve on the same cylinder. Just keep going cylinder to cylinder. People think that a valve can actually fall down into a cylinder, but not on a 3.48" stroke motor. Fortunately valves are a lot longer than the stroke of the motor.
Old 12-16-2007, 09:06 AM
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I use a magnetic pickup tool for the locks.
Old 12-16-2007, 02:13 PM
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I wouldn't suggest trying joelster's method. Too easy to damage valves, and it's not trivial to get the new springs on if they are stout. A valve spring swap at a competent performance shop should cost you between 150 and 300 bucks.

If you do do it yourself, spend some of the cash you save on renting (or borrowing) an air compressor, and buy yourself the air holding adapter for 20 or 30 bucks. You MUST have a on-car spring compressor (not all will work, I use one that is H-shaped and goes on the rocker stud), MUST block the oil drains, and a magnet on a stick helps a LOT. Small tip.

Also - doing it yourself allows you to get obsessive about correctly setting installed height. This will give you correct seat and open pressures. You'll need a special tool for this, runs about 80 bucks.

In all honesty, having a GOOD shop do the work is worth it if this will be the only time you swap springs; if you might do it again later a number of times, invest in the tools and learn how, so you can save bucks down the road. You won't save much cash if you invest in the tools needed to do it right this time... but you'll have the tools.
Old 12-16-2007, 04:04 PM
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Originally Posted by Boodyrider
I wouldn't suggest trying joelster's method. Too easy to damage valves, .
Are you kidding me? How exactly are you going to damage a valve? Think it through for a second.
Old 12-16-2007, 06:47 PM
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thanks i will take both of your methods in consideration
Old 12-16-2007, 07:07 PM
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i have also heard of doing it by moving each piston to top dead center and just taking the spring off from there...valve falls but not far enough that its gone into the motor lol magnet helps too
Old 12-16-2007, 08:00 PM
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Originally Posted by Orr89rocz
i have also heard of doing it by moving each piston to top dead center and just taking the spring off from there...valve falls but not far enough that its gone into the motor lol magnet helps too
Yeah you move the piston to TDC THEN pull the springs. The seals may hold the valve up a little but should not be counted on.

Done it a couple times, never used air. I have a tool like this http://buy1.snapon.com/catalog/item....store&tool=all they are available cheaper under different brand names. Not the fastest but compact and I like to be able to lift the spring seating the locks and then release it lowering it into the seat. A lever type is faster where there is room but you better not slip andlet go of the lever.
Old 12-16-2007, 08:36 PM
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Originally Posted by Orr89rocz
i have also heard of doing it by moving each piston to top dead center and just taking the spring off from there...valve falls but not far enough that its gone into the motor lol magnet helps too

/\ X3
Old 12-16-2007, 08:45 PM
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You can go to your local auto parts store and pick up a valve spring compressor that cranks from the top for about $20 and an air cylinder tool for the sparkplug hole for like $10 i think.
Old 12-17-2007, 10:13 AM
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Originally Posted by Orr89rocz
i have also heard of doing it by moving each piston to top dead center and just taking the spring off from there...valve falls but not far enough that its gone into the motor lol magnet helps too
did it this way with a crane cams spring compressor. It made the job possible with double springs vs single.



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