LLT V6 stock flowrates....simply sad!

[bmwdon]

not sure about the valve guides as those are pressed in at the top, what is visible in the shots are the heads material in the bowl...I don't think they are there as structural as the pressed in part at the top of the head, I think he'll clean those up a little bit. And they are on the exhaust side, if any bits chip off, they should go out the headers.

and in the 3rd shot, again, the exhaust ports are matched to the headers, simply hogging them out and not matching the 1 5/8" header runners would cause the exiting air to be distrupted and loose velocity

[Beauwulf]

I was referring to the area marked below as far as the radius on that ledge...

[bmwdon]

don't know?? he's the head guy, I defer to his knowledge over my lack of

[Beauwulf]

Originally Posted by bmwdon

don't know?? he's the head guy, I defer to his knowledge over my lack of

I hear ya brother! It's amazing how close these are to late model motorcycle heads! The intake angle being the only real difference. I may have to start looking for a set of heads for mine! hehe!

[bmwdon]

you got PM

[NXC1978]

Originally Posted by bmwdon

I don't, but Matt might, not sure if he took shots of those or not, I'll ask. I did post up pics of the porting he did on the first head, just no valve job cut yet. These are all I have at the moment.

And all the wife knows for now is the headers back exhaust and cai... too scared to tell her about the rest, and she's not technical enough to know if I did this or not

Those photos are glorious!

[matt d.]

Originally Posted by Beauwulf

I was referring to the area marked below as far as the radius on that ledge...

You can't really remove much more metal in that area or it will break through into the oil galley that feeds the followers. These intake ports have a funny shape compared to most OHC heads. That part of the port is the roof of the intake port. The port comes in straight and then turns up. The cross sectional area there is pretty large stock and does not need much work unless you were to put a larger valve in. The same goes for the floor of the port just a little further in I would have liked to remove a hump in the floor but could not because it would break through were the injector boss is. Ideally I would like to make the port as straight as I can, but GM most likely for dimensional reasons could not make the port that straight and maintain hood clearance.

[bmwdon]

thats why I let the pro do it....my diy self would have just took a grinder to it all and not until I broke through a oil or coolant passage would I have realized I made a booboo and by that time, it's too damn late!

[Beauwulf]

Originally Posted by matt d.

You can't really remove much more metal in that area or it will break through into the oil galley that feeds the followers. These intake ports have a funny shape compared to most OHC heads. That part of the port is the roof of the intake port. The port comes in straight and then turns up. The cross sectional area there is pretty large stock and does not need much work unless you were to put a larger valve in. The same goes for the floor of the port just a little further in I would have liked to remove a hump in the floor but could not because it would break through were the injector boss is. Ideally I would like to make the port as straight as I can, but GM most likely for dimensional reasons could not make the port that straight and maintain hood clearance.

Cool... I figured there was a reason. What flow rate did you get at .500 after the work?

You could get one of these units to test the material remaining... just to be sure...

http://www.ndt.org/news.asp?ObjectID=21942

[Orange5thGen]

How can I get a set of heads worked like this? Will a new tune be required?

[speedster]

Good Thread, but your title is misleading.

These heads on the V6 at the price GM charges for the base Camaro are WAY better than the heads of the previous corporate V6's. e.g the 3.1 - 3.8 liter series on cars over the past 20 years. I would bet they optimized the V6 for mileage and then power. So I wouldn't be slamming them too hard.

On the flip side, it's nice to see some HP tech on the V6 components. Thanks for the info/postings !! If it worked out that you had a core set to start an exchange program, you may get a bunch of business next year when people park their rides for the winter and think of modifications.

Please list the post port flow numbers. That will be cool to see the diff. Did you by chance get a chassis dyno run or track run of "her" car before you pulled it? It would be great to see the improvement...

[matt d.]

Originally Posted by Beauwulf

Cool... I figured there was a reason. What flow rate did you get at .500 after the work?

You could get one of these units to test the material remaining... just to be sure...

http://www.ndt.org/news.asp?ObjectID=21942

.500" 327 cfm. I will give bill the rest of the numbers first. I have a sonic tester for testing the thickness of the material. If we were using a big valve and if it was for a race application with big cams needing to turn alot more rpm I would really have to start moving some metal.

[bmwdon]

Matt, can't wait to see all the #'s....327 on the intake side is quite a jump, especially when you said there's wasn't much to gain on that side ....so lets see all the #'s!!

Originally Posted by Orange5thGen

How can I get a set of heads worked like this? Will a new tune be required?

check the wiki page on the LLT engine and see what other cars have this engine and search the junk yards, they can be had for $400-500 a pair. Then you'll need to talk to a head guy....(ahem..Matt D. ) and figure on a price on headwork. And I'm pretty sure you're going to want to get a custom tune to get this setup working right!

[esperman]

hmmmm....we may be seeing 300 rwhp sooner than I thought!