Valve springs and leakdown test

[captndave737]

Ive never replaced my valve springs and I figure it's time. What springs should I get? Part #'s. Stock engine street driven.

I have 150-155 lbs. on all cylinders when I do a compression test. Is there any reason to get a leak down tester or can I just hook my compressor up and see what happens. I know you have to be at TDC on each cylinder.

 

[thadeal4real]

you cannot just hook a compressor up you need a set of gauges the leakdown will tell you what type of condition your valves valve seats and possible Rings are in why would you need to change your springs just because you think its time though?

 

[fastblackracing]

Ive never replaced my valve springs and I figure it's time. What springs should I get? Part #'s. Stock engine street driven.

I have 150-155 lbs. on all cylinders when I do a compression test. Is there any reason to get a leak down tester or can I just hook my compressor up and see what happens. I know you have to be at TDC on each cylinder.

Comp cams 980 springs have worked well for me on several cars that I have put them on with stock cams. Does your engine pull clean all the way to 5500 rpm? If it does you springs are still good although at 204k? miles it would be hard to Believe. Your compression numbers look good as long as your not using oil I think your in good shape. Are you having any issues or just doing some maintenance? I would be more concerned about the plastic teeth on the timing chain gears myself.

 

[captndave737]

Comp cams 980 springs have worked well for me on several cars that I have put them on with stock cams. Does your engine pull clean all the way to 5500 rpm? If it does you springs are still good although at 204k? miles it would be hard to Believe. Your compression numbers look good as long as your not using oil I think your in good shape. Are you having any issues or just doing some maintenance? I would be more concerned about the plastic teeth on the timing chain gears myself.

I use almost no oil now that I have no leaks. I'm not having any issues just doing maintenance. It pulls strong to about 4800 rpm and not so much after that. I put a KB double roller timing chain on when the car was practically new and a TA Performance silent link chain on last year. More like 208 k on the car now.

 

[fastblackracing]

I use almost no oil now that I have no leaks. I'm not having any issues just doing maintenance. It pulls strong to about 4800 rpm and not so much after that. I put a KB double roller timing chain on when the car was practically new and a TA Performance silent link chain on last year. More like 208 k on the car now.[/Q I would suspect that you probly have some valve float/bounce above 4800. The stock cam starts giving up some power over 5000, but it should pull clean to 5500. If your happy with it being good to 4800 then no need to upgrade the springs. New springs will probly help it some over 4800, how much hard to say. If you do change them out I would be curious as to what kind of pressure a 200k stock spring has left in it. One of my friends car picked up a full second and 10 or so mph with a spring change, but you could hear it in his motor up at the top of the gears it just did not sound clean. Let me know if you change them how it turns out for you.

 

[captndave737]

Thanks fastblackracing. I'll probably change them since it's cheap and easy and the pull flattening out drives me nuts. I also get bored in the winter and need projects.

The end of next summer I'll be taking the car off the road for a couple of years to do a frame off build.

 

[captndave737]

Ok. So I'm going to throw in a set of Comp 980's. Can I use the stock retainers with them? I'll have the old ones tested when I take them out and let you know what the rate is.

 

[bison]

Ok. So I'm going to throw in a set of Comp 980's. Can I use the stock retainers with them? I'll have the old ones tested when I take them out and let you know what the rate is.

I wouldn't throw in any spring. Measure the pressures then install at the correct height to get the pressure you want


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