IRACE87

I'm wondering what kind of positive seals you guys are using.
On the intake and exhaust.

I know Fel-Pro SS72527 looks good for the intake valves but I can't find anything similar for the exhaust.

Any suggestion.

PAT

deepstage69

iTrader: (2)

I dont know what part number i used, but i used two sets of intake seals, put intake seals on intake and exhaust.

Kevin

IRACE87

How would the Fel-Pro Viton seals hold up on the exhaust ?? I wonder.....

It's hard to get good info on valves seals, it's not something that gives more HP so people don't really think about them that much.

PAT

iroczracer07

iTrader: (2)

Fel-Pro's level of quality for valve stem seals is always at least that of original equipment. Service life, not cost, dictates the materials required. Although seals made of premium materials, such as VITON® or polyacrylate, are much more expensive than seals made of nitrile, they represent but a small fraction of the total repair cost. Therefore, it just doesn't make good economic sense to sacrifice a long-lasting, successful repair to save on the cost of the valve stem seals. With Federal-Mogul's Fel-Pro valve stem seals, you'll do the job once, and do it right the first time.

That should help in your decision I think.

phess11

Use Fel-Pro SS72527 on both the intake and exhaust. They are positive type Viton.

IRACE87

The Fel-Pro SS72527 are for the intake valves. Is it because of the material they are made of (heat resistance) or because of the amount of oil it will control ????

PAT

phess11

both

IRACE87

Now I wonder how long Viton seals would last on the exhaust.

Maybe I should stick with teflon seals on the exhaust but I never had a great success with them in the past.

PAT

phess11

Here are some Viton Positive Seals from Comp Cam, Edelbrock, and Trick Flow for both intake and exhaust.

http://store.summitracing.com/defaul....asp&x=22&y=11

redbird_400

That is about the most resourceful valve seal link that I have seen so far!

IRACE87

PAT

redbird_400

The worst part is that.. we all knew jegs.com existed but only one recently had the motivation to pull the link lol. I'm currently replacing my valve seals, the intake and exhaust valve seals that were on my car look like this.

http://store.summitracing.com/defaul....asp&x=22&y=11

The new ones have been a pain to slide on. I'm tapping them on with a small deep socket as light as I can but I already cracked one trying this method, fun.

Stekman

Most of the seals listed there would require machining of the valve guide boss. You can't force a seal designed for .530" over a boss that is closer to .562"

redbird_400

yea, the ones that I got from the parts store must be to small. This pic shows where they get stuck. I need to just get a precision measuring tool rather then wasting money the wrong parts...

redbird_400

Ok I think I just found the answer to my problem. Near the botton of this article it explains how its safe to use the viton seals in place of factory nylon seals. They say that the vitons can hold up to heats of 450 degrees as the cylinder head often raises about 300 degrees. My valve stems must be oversized by a small bit because the fel-pro SS 72526 seals do not fit.

Here is a helpful link on valve seals.

http://www.federal-mogul.com/cda/con...6_7501,00.html

phess11

What engine do you have?


According to PartAmerica.com 72526 and 72527 should fit. I used 72527 on both intake and exhaust.

Stekman

Make sure you apply some oil to the insides of the valve seals and the valve stems themselves. That will help them slide down.

redbird_400

yea, your right, they "should" have fit. Its a stock 305 that came from an 89 RS Camaro, same L03 that was originally in the 89 bird. The engine was said to of been rebuilt by the dude who sold it to me. The intake/viton fit prefectly but the exhaust valve seals cracked no matter how lightly I put them on or with oil on the valve stem. I said screw it and put the 400 degree viton seals on intake and exhaust. On fel-pro's website they did have a car as an example of where they had to use viton on both intake and exhaust, it posed no problem since they can withstand high temps. If they give me anymore problems I'm going with my next upcoming solution that will fix many problems, the 350 swap.