Who can teach me about heads?

[DarkProphet]

Hey guys, ive had no luck selling my car thus far, and any offers i did get were in the 3k range. So im going to attempt to fix it. I would idealy like a new motor, but I think im giong to try new heads first. The problem is I know NOTHING about them. Ive taken the stockers off twice now (HEAVY!!). the kind of information im looking for is the difference between rocker setups (pedestal and stud), and valves and all that stuff. What kind of rockers are the stock ones? Im assuming pedestal, but thats jut a guess. Also, what are the differences between hydrolic cam and roller cam rockers? Im pretty mechanically inclined and go to school for engineering so i understand alot, just never really read up on heads or rockers or cams. Any info anyone may have would be great!

Anyone have a set of gt40's they would like to sell me??

 

[urban96]

stock heads have pedastal mount rockers, also pretty much any ford factory head will have pedastal mounts (gt40 family)

you can find gt40/gt40p heads on ebay or over on the corral.net classifides for a decent price

im curious tho why youve had the heads off twice so far?

 

[95GTV8]

he's blown alot of headgaskets :/

 

[mytight95]

yup, honestly i would take the engine out, and to a machine shop(get the block decked or something) or at the very least check it to make sure it is uniform


jason

 

[DarkProphet]

well the block has 110k miles onit. BUT i just aquired a 50k mile block with gt40x heads on it, and a B cam! So im just going to swap the engine out and have a fresh mill!

 

[mytight95]

that sounds like a very good option for you....... I would at least check the compression on the motor while it is out of the car..... the new one... you know beforeyou go through the trouble of putting it in....



jason

 

[Pokageek]

I am still interested in the topic though and no one is talking about it. What are the 58 vs 64cc ratings? What does that mean? What is a 2.02 valve vs a 1.9x valve mean? My heads are crappy shimmed ported e7's with re gournd valves and it starts up like an old car that hsa to warm up or it can backfire sometimes. I am assuming this is b/c the crappy heads.

 

[mytight95]

a lower number cc chanber is gonna yield more compression. I think it is one compression point higher for every 8cc you lower the cahmber......


2.02 valve vs, 1.9 valve is just the actual valve diameter.. 2.02" versus 1.9"

I have ported e7's, they have 1.90, 1.60 valves, they do pretty good but i know there is power to be had with a head swap (in the near future) If they didn't seat the valves right etc, or do the valve seats right etc, i guess it could cause a problem, but i don't think it would cause a backfire....maybe check to see that the rocker arms are shimmed correctly...



jason

 

[Pokageek]

a lower number cc chanber is gonna yield more compression. I think it is one compression point higher for every 8cc you lower the cahmber......


2.02 valve vs, 1.9 valve is just the actual valve diameter.. 2.02" versus 1.9"

I have ported e7's, they have 1.90, 1.60 valves, they do pretty good but i know there is power to be had with a head swap (in the near future) If they didn't seat the valves right etc, or do the valve seats right etc, i guess it could cause a problem, but i don't think it would cause a backfire....maybe check to see that the rocker arms are shimmed correctly...



jason

Thanks man. I guess that is why the co that made my engine said don't go below 62cc with my pistons. They are a flat type piston. I heard you can get "dome" shaped pistons for more compression too but don't know why anyone would get those as upposed to better heads.

I have also wondered how you determine the "valve clearance" issue I keep hearing about. I am not even sure what that means or how it relates to th 1.9x, 1.6x vs 2.02?

 

[CManT1914]

Thanks man. I guess that is why the co that made my engine said don't go below 62cc with my pistons. They are a flat type piston. I heard you can get "dome" shaped pistons for more compression too but don't know why anyone would get those as upposed to better heads.

I have also wondered how you determine the "valve clearance" issue I keep hearing about. I am not even sure what that means or how it relates to th 1.9x, 1.6x vs 2.02?

Valve clearance is the relation of the piston to the valve during engine rotation. You MUST have a certain amount of PTV (piston to valve) clearance, otherwise your pistons will slap your valves as they rise and bend them all up. Most heads will say whether they work with a stock pistons or not. I believe that TFS are the only heads with 2.02" intake valves that work with stock pistons. I thought Edelbrock offered some, but somebody told me they don't. I know the basics of checking PTV clearance, but can't figure out how to explain it right now (braind dead, lol). Maybe somebody else will chime in.

 

[mo_dingo]

Try www.howstuffworks.com It has info on anything you can think of.

Also, try searching on this forum. There are hundreds of threads concerning this.
Scott

 

[Pokageek]

"Change the heads and cams -- Many stock engines have one intake valve and one exhaust valve. Buying a new head that has four valves per cylinder will dramatically improve airflow in and out of the engine and this can improve power. "

So why don't they make after market cylinder heads for our cars with 4 valves per cyliner instead of 2??

To tell you the truth I am unsure of why the guy told me don't go below 62cc? SHouldn't he be saying don't go above?

 

[CManT1914]

"Change the heads and cams -- Many stock engines have one intake valve and one exhaust valve. Buying a new head that has four valves per cylinder will dramatically improve airflow in and out of the engine and this can improve power. "

So why don't they make after market cylinder heads for our cars with 4 valves per cyliner instead of 2??

To tell you the truth I am unsure of why the guy told me don't go below 62cc? SHouldn't he be saying don't go above?

Because our block aren't set up to open and close 32 valves. We only have space for 16 pushrods, not 32. The modular motors don't have pushrods, the cams open the valves more directly, so they save space. To fit 32 valve heads on a 5.0, you'd spend so much money you might as well buy a space shuttle.

 

[Pokageek]

Thanks Cman. I think I have the answer to the other question now too. Without going into a lot of detail that I don't have anyway, sounds like he was saying go 62cc or higher because the more volume or cc's, the lower the compression.

Meaning if I compress in a smaller cc area than 62cc, then the compression for my flat top pistons will be to high and cause detonation. I think I get the gist now.