Valve job questions for ya....

[redterror302]

I have a few questions for you guys/gals. I will soon be starting to home port some stock e7's to try to get a bit more power. I don't have a spring compressor yet so there is nothing I can do right now. By visual inspection, the valves do look good, so I want to take them to get a valve job done. With my setup I will have(see sig), would you recommend a 3 angle or a 5 angle valve job. Also, are there certain angles that need to be cut into the valves? I didn't know if there are better angles then others, as well as the length of that certain angle's side. Should the machine shop know what they are doing with this?

I am still in the process of finding a good machine shop near my new place. Another question, approximately how much would this cost me. I know prices vary by areas and such, but could someone give me what they think a good price would be?

Do I need to bring in the heads to the machine shop as well, or just the valves(don't know if they do anything to the head)? It's be nice if I could just bring in the valves, well because they are light. Those e7's are heavy suckers! Also, when I go to reinstall everything, is there a certain way to put the valves back in, or do I just lock in the springs and go? I hear a lot of talk about valve geometry and how it can be off and such. I don't want to go through all of that work just to have to do it again.

I'm done with my questions now, I swear .

Any help I could get would be appreciated.

Thanks,
Chris

 

[wildstang347]

yes the heads do need to be brought in.........and the five angle cut is more preferable. (better flow benefit)
most machine shops useually only do a 3 angle valve job, but have the set up to do 5 angle. average cost around were i live is 50$ a head
just ask 2 talk with machinist and question him about weither hes familiar with doing a 5 angle cut instead of the common 3, letting him know your intentions with the heads.
i personally am very picky with who i let do my machine work. i have 2 feel comfortable with the persons knowledge & skill, before giveing them my business, because engine tolerances 2 me can be pretty critical at power & RPM ranges im accustomed 2.
as far as the home porting...............dont go hogwild with the carbide cutter, just remove highspots in the pockets (flashcasting) and pay more attention 2 the exhaust side with the sandpaper rolls.
theres been plenty of articles in past few months in popular hotrodding on home how to port heads.
before and after photos of procedures with decent descriptions were to concentrate work on.
on any head when doing bowl work if 2 much material is removed from wrong areas altering bowl shape, flow figures can be hurt.
always best to just smooth and blend the pockets with no prior knowledge (first time) usually cant go wrong.

 

[thumper460]

Listen to Wildstang347... The 5 is a good performance valve job, the back cut on the valve is also called the " flow cut" at a few shops, it really increases low lift flow at the valve!! Talk to the shop. and really... dont go nutz with the cutter!! As wildstang said... you can come away worse than when you started!! gasket match the intake and then remove the egr bump in the exhaust, just smooth the sharp angles in the bowls... and you'll be rocking!! Then take it ALL to the shop!! E7s heavy?? yeah, 50 Lbs... but the GT40s are heavier!! they weigh 10% more!!
Have fun.. and get a few dust masks...lol

Just me.........................

Thumper

 

[Maryland Stang]

You might want to take the heads in before you do any work to them and have them magnafluxed. There's nothing worse than doing a whole lot of work to a head only to find out that it has a crack in it. Just disassemble the head and clean any grease or oil off of it before you take it in.

 

[Roger Ramjet]

From the questions you are asking, I would recommend that you not grind on the heads yourself.

 

[redterror302]

From the questions you are asking, I would recommend that you not grind on the heads yourself.

Thanks , but I think I will be fine I know how to port, just didn't know what all is involved in getting a valve job done. I ported my intake myself with good results, and already practiced porting a set of e7's that my friend had. Plus if I have any questions, thumper is always there for me! Actually, along with his help, I have this site: http://www.cmc.net/~xero/Mousesporting.html

The site gives a step by step process on how they ported the e7's, and what the flow numbers were after each individual thing he goes over. It also shows what didn't work, and shows how much he lost doing it. If I can get close to what he has, then I should be flowing over 200 cfm intake, and around 150 cfm exhaust. That's not bad in my opinion.

Thanks to those who replied, I could use any hints or tips you could give me.

Chris

p.s. What about the question on valve geometry? This is going to be the first time I assembled heads.

 

[redterror302]

ttt

 

[redterror302]

ttt

 

[redterror302]

anyone?

 

[redterror302]

sure could use some answers.....................