At What Point Is A Valve Job Necessary?

hoopty5.0 · Jun 8, 2015

To say that the budget for my fox is tight is an understatement at the moment. I snagged some P heads last week for $100 and need to buy the $105 spring kit from Alex parts.

The question is, how do I know if I absolutely have to have the seats re-cut? I have a right angle die grinder with scotch brite pads and cleaned everything up, nothing seems obviously wrong. Since they are just P heads and I am not trying to set any records, I could probably just roll with it, correct? What should I look for?

Bullitt347 · Jun 8, 2015

If the valves are seating all the way around, the next thing to look for is valve guide wear. If the guides are good, slap some new seals and springs on them and run them. You can always fill the ports with fluid and look to see if any fluid leaks past the seat. If it holds fluid you are good to go.

Boosted92LX · Jun 8, 2015

^^Good advice. If they fail the fluid test you can reseat them with clover lapping compound and an elctric drill..

Works in a pinch.

FoxMustangLvr · Jun 8, 2015

^^What they said.

Are you going to at least get them checked for flatness to ensure a good mating surface to the gasket & block?

hoopty5.0 · Jun 8, 2015

Bullitt347 said:
If the valves are seating all the way around, the next thing to look for is valve guide wear. If the guides are good, slap some new seals and springs on them and run them. You can always fill the ports with fluid and look to see if any fluid leaks past the seat. If it holds fluid you are good to go.

That's another thing - I have always thought heads had bronze guides. These do not, it's just part of the head.

But yes, I will check the deck on them.

Boosted92LX · Jun 8, 2015

hoopty5.0 said:
That's another thing - I have always thought heads had bronze guides. These do not, it's just part of the head.

But yes, I will check the deck on them.

I'm pretty sure bronze are installed and reamed to size when a shop refinishes them. Factory reams the cast iron to size.

hoopty5.0 · Jun 8, 2015

So I'd assume if the guides are too worn, there would be slop and the valve would move around in the guide? They all seemed very tight as I removed them.

Boosted92LX · Jun 8, 2015

hoopty5.0 said:
So I'd assume if the guides are too worn, there would be slop and the valve would move around in the guide? They all seemed very tight as I removed them.

If that's the case, set them with the chambers facing up and fill them with water. If they hold, install new seals and run em.

FoxMustangLvr · Jun 8, 2015

Yes, they'd move and air would get around the stem. I'm just going to say this because we'd all say this to any noob asking, save your $$ and get those dang heads hot tanked, magged, new valves, 3 angle, along with the new springs etc. Once you install these heads they're likely not coming off for a long time. It's worth the extra couple hundred bucks or so.

hoopty5.0 · Jun 8, 2015

FoxMustangLvr said:
Yes, they'd move and air would get around the stem. I'm just going to say this because we'd all say this to any noob asking, save your $$ and get those dang heads hot tanked, magged, new valves, 3 angle, along with the new springs etc. Once you install these heads they're likely not coming off for a long time. It's worth the extra couple hundred bucks or so.

Well, before I take them anywhere or buy anything, I'm going to do a little port work. The EGR bump is going to be removed in the exhaust port and a couple of areas in the intake port will get massaged. From what I've read, those 3-4 small changes net large results in the mid range lift flow numbers.

I will get the heads checked, but I don't want to spend money on processes that aren't necessary.

FoxMustangLvr · Jun 8, 2015

Did you go to the gt-40 website that documented the porting process and flow benched each step of the porting process and documented where the flow was improved at a certain lift point and what areas where hurt during the porting process?

hoopty5.0 · Jun 8, 2015

FoxMustangLvr said:
Did you go to the gt-40 website that documented the porting process and flow benched each step of the porting process and documented where the flow was improved at a certain rpm range and what areas where hurt during the porting process?

Yup.

hoopty5.0 · Jun 8, 2015

That was really cool how they did that. I absolutely will not get that advanced, but I will pick the low-hanging fruit. I may get 5 hp out of it, but anything that helps the mid range is a win in my book.

FoxMustangLvr · Jun 8, 2015

The extra HP from porting plus a smaller combustion chamber with the P's should give you some fun butt dyno time. What else are you doing when you replace the heads? Explorer intake? Ported? Cam?

hoopty5.0 · Jun 8, 2015

Im going to pull the whole motor apart and see what kind of shape it's in. But the end game is an 'explorer' top end and a small cam of some sort. This car is grossly underpowered. Im ashamed to admit I had trouble passing a Mazda SUV the other day getting on the freeway going to work.

FoxMustangLvr · Jun 8, 2015

Are you at least geared?

hoopty5.0 · Jun 8, 2015

FoxMustangLvr said:
Are you at least geared?

Yeah, for the highway

squeak93 · Jun 8, 2015

I drove my 2.73 geared aod power house today. Had to down shift going up a bridge lol.

I have a similar combo in the works but with three bar heads and a five speed swap. Good thread.

A5literMan · Jun 8, 2015

I should have an e cam available for cheap( if you're interested) fairly soon.

hoopty5.0 · Jun 8, 2015

I just ordered 4 carbide bits for iron off eBay for $44 shipped. let the games begin!

At What Point Is A Valve Job Necessary?

mechanicus terribilis

I have been doing it wrong this whole time

It's only an inch or two. What's the big deal?

I love my Pimp

mechanicus terribilis

It's only an inch or two. What's the big deal?

mechanicus terribilis

It's only an inch or two. What's the big deal?

I love my Pimp

mechanicus terribilis

I love my Pimp

mechanicus terribilis

mechanicus terribilis

I love my Pimp

mechanicus terribilis

I love my Pimp

mechanicus terribilis

At least it is lumpy...

mechanicus terribilis

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