[WhiteLightening]

Is it worth it consider porting out our cyclinder heads? I've thought of doing that, but wondering if anyone had done this on the gen5 v6, or the current gen LGX motor. Every time I've seen someone port the heads and engine block the procedure has proven positive results. Do y'all think that would be the same with ours?

[PolynesianPowerhouse]

Originally Posted by WhiteLightening

Is it worth it consider porting out our cyclinder heads? I've thought of doing that, but wondering if anyone had done this on the gen5 v6, or the current gen LGX motor. Every time I've seen someone port the heads and engine block the procedure has proven positive results. Do y'all think that would be the same with ours?

I know its been discussed here before, but the exhaust side is the main part of porting that will be almost impossible. extrude honing would be the method, but something like that is usually done on iron heads, or manifolds due to the abrasiveness...



around 40 seconds into the video, you'll see your exhaust runners in a cut away segment. with porting, you can only port what you can see and reach. short of cutting a head in half, you're not gonna be able to see and reach the exhaust sides... lfx engine had the same design.

if you listen to the vid though, its actually lighter, flows better, and more efficient than individual runners where you have to upgrade to headers from a manifold.


can it be done... I'm sure someone has or can find a way.... however what will they charge? who knows. we have guns that can shoot around corners, micro cameras used as bore scopes, so if there's a will there's a way... but most currently pay 800-1100$ for porting of v8 heads... how much more is the issue you'll run into for something most cant see. I mean you can trim some flashing around the opening. but a good port job also includes right where the valves open as well, which is what cant really be reached on the exhaust side of our heads.

[WhiteLightening]

Originally Posted by PolynesianPowerhouse

I know its been discussed here before, but the exhaust side is the main part of porting that will be almost impossible. extrude honing would be the method, but something like that is usually done on iron heads, or manifolds due to the abrasiveness...



around 40 seconds into the video, you'll see your exhaust runners in a cut away segment. with porting, you can only port what you can see and reach. short of cutting a head in half, you're not gonna be able to see and reach the exhaust sides... lfx engine had the same design.

if you listen to the vid though, its actually lighter, flows better, and more efficient than individual runners where you have to upgrade to headers from a manifold.


can it be done... I'm sure someone has or can find a way.... however what will they charge? who knows. we have guns that can shoot around corners, micro cameras used as bore scopes, so if there's a will there's a way... but most currently pay 800-1100$ for porting of v8 heads... how much more is the issue you'll run into for something most cant see. I mean you can trim some flashing around the opening. but a good port job also includes right where the valves open as well, which is what cant really be reached on the exhaust side of our heads.

So we can't just take the head off and rotate, then bore the exhaust side?

[PolynesianPowerhouse]

Originally Posted by WhiteLightening

So we can't just take the head off and rotate, then bore the exhaust side?

You always take the heads off to do a legit port job. Thats a given that goes without saying.

But did you not see the angles of the runners in the exhaust port in the video?

Remember the video shows a cut away of the heads so you can see inside the exhast ports and runners.

The only access in the real world, is the single exhaust port for all 3 runners...

Mandrels for porting cylinderheads are long and straight.

Which is why a regular set of heads the intake runner is relatively straight and the corresponding exhaust port and runner is on the opposite side relatively straight as well.

[WhiteLightening]

Originally Posted by PolynesianPowerhouse

You always take the heads off to do a legit port job. Thats a given that goes without saying.

But did you not see the angles of the runners in the exhaust port in the video?

Remember the video shows a cut away of the heads so you can see inside the exhast ports and runners.

The only access in the real world, is the single exhaust port for all 3 runners...

Mandrels for porting cylinderheads are long and straight.

Which is why a regular set of heads the intake runner is relatively straight and the corresponding exhaust port and runner is on the opposite side relatively straight as well.

Yeah, I hadn't watched the video when I posted the previous reply. The video answered the question I had about flipping the head....until there are flexible mandrels we will never have that.

So a 5th gen camaro high flow down pipe and cats would be able to mount up to the exhaust runners perfectly...

[PolynesianPowerhouse]

Originally Posted by WhiteLightening

Yeah, I hadn't watched the video when I posted the previous reply. The video answered the question I had about flipping the head....until there are flexible mandrels we will never have that.

So a 5th gen camaro high flow down pipe and cats would be able to mount up to the exhaust runners perfectly...

I have no doubt thats theres probably something that can be used (flexible) but the avg engine shop prob doesnt have it readily available given most heads have runners on opposite sides of the head.

For a majority part of the runner the idea is to smooth and polish the exhaust side. Clear any flashing or casting seams remaining from manufacturing.

Gasket matching isnt done as much on the exhaust side due to you want to leave a small bit of wall inside the gasket for the exhaist pukse to keep from reverting back into the head. Its part of the scavenging process on the exhaust pulse.

On the 5th gens with llt engine. Easy to do... for each intake runner there is a separate exhaust runner on the opposote side of the head. That's why they have headers for that engine.

But the lfx would be yhe same as the lgx in design. 3 runners converging into one single exhaust port.

And lastly...cost... extra work to do a set of heads can charge extra money. Most here complain about 400$ for an intake. Are many here gonna shed 800$ or more for a mod that would give you potentially equal whp to that of an intake???

Dont forget the cost of removing heads and replacing the head gaskets and basically ans upper engine rebuild.

Would be nice to attempt during a build, and def a beneficial mod. But as a singular mod, very expensive



As for mounting a 5th gens stuff from the lfx to the lgx. Dustya said something about it fitting but you had to mod a bend in it somwhere. So to me thats not a perfect fit if you have to add an extra bend in intake or exhaust.

I do know dustya mentioned he had his own custom made. Once again...i doubt it was astronomical in cost, but most realistically wont invest time or effort into simply getting a downpipe fabbed up for a few reasons. For those that go catless, tuning will be required. If you dont get to the point where this mod is beneficial (like dustya being boosted) then you have to know what size pipe will keep the velocity up and flow as good or better than stock. (More or less stock size pipe just mandrel bent).

[WhiteLightening]

Originally Posted by PolynesianPowerhouse

I have no doubt thats theres probably something that can be used (flexible) but the avg engine shop prob doesnt have it readily available given most heads have runners on opposite sides of the head.

For a majoroty part of the runner the idea is to smooth and polish the exhaust side. Clear any flashing or casting seams remaining from manufacturing.

Gasket matching isnt done as much on the exhaust side due to you want to leave a small bit of wall inside the gasket for the exhaist pukse to keep from reverting back into the head. Its part of the scavenging process on the exhaust pulse.

On the 5th gens with llt engine. Easy to do... for each intake runner there is a separate exhaust runner on the opposote side of the head. That's why they have headers for that engine.

But the lfx would be yhe same as the lgx in design. 3 runners converging into one single exhaust port.

And lastly...cost... extra work to do a set of heads can charge extra money. Most here complain about 400$ for an intake. Are many here gonna shed 800$ or more for a mod that would give you potentially equal whp to that of an intake???



Dont forget the cost of removing heads and replacing the head gaskets and basically ans upper engine rebuild.

Would be nice to attempt during a build, and def a beneficial mod. But as a singular mod, very expensive

I heard the single outlet that connects to the exhaust matches perfectly up the 5th gen down pipes and exhaust set ups . So I was thinking of trying that eventually. You think a basic exhaust shop could make me a x pipe to fit on my stock exhaust and replace the h pipe?

[PolynesianPowerhouse]

Originally Posted by WhiteLightening

I heard the single outlet that connects to the exhaust matches perfectly up the 5th gen down pipes and exhaust set ups . So I was thinking of trying that eventually. You think a basic exhaust shop could make me a x pipe to fit on my stock exhaust and replace the h pipe?

Check the last part i added above about downpipes.


Any exhaust shop thay does decent work can do that. It's what they do for a living. If a place cant do something thst simple, they wouldn't touch my car.

One more note with the porting job, always understand that if there's truly a will then there's guaranteed to be a way to get it done. Just because traditionally used methods might not be as effective, when I mention "extrude honing", that's another way of using a paste to do the work as it's being flowed through the head, which is abrasive enough to complete the work that porting would do in just a chemical form.

When it comes to cars the question of the day of whatever mod you want to do will always fall back on how far do you want to dig in your pockets to get it done.

Usually a mod like this is done when cams are changed out or any work to the upper part of the engine is done to where disassembly is required.

And once the work is done as with anything with air flow or exhaust flow you always want to have flow bench testing done before and after. It's not uncommon for a head to be ported by someone who isn't isn't as savvy with certain style or brands of heads, and they actually decrease the performance. For example there was a local guy that goes to the same shop as me he tried to open the exhaust Runners little bit too far and it's slow the velocity he also attempted to polish the chamber's but actually lower compression ratio by removing too much material. Generally good if you're going to go boost it or maybe nitrous but for the na build that he was shooting for it put him a few steps back.

So just remember not saying that it's impossible to get done it's just going to require a bit more tools and or work which more than likely will put the price of the job Out Of Reach for the average person on the forums

[DSX_Camaro]

If you really wanted more power N/A it would probably make the most sense to sleeve the cylinders and bore them out a tad / a lot. Throwing boost at it is the best bang for your buck though, especially considering how modular the kits are.

If you were interested in staying N/A, I'd say you should invest in the Overkill tune and see if Will would let you test the 80mm TB and ported intake manifold. On our cars the ported manifold was big power (relatively speaking). That, and you should look at gears. Engine work on something as complex as a VVT DOHC V6 is not easy considering the lack of investment and support. There are other, better options.

[WhiteLightening]

Originally Posted by DSX_Camaro

If you really wanted more p
ower N/A it would probably make the most sense to sleeve the cylinders and bore them out a tad / a lot. Throwing boost at it is the best bang for your buck though, especially considering how modular the kits are.

If you were interested in staying N/A, I'd say you should invest in the Overkill tune and see if Will would let you test the 80mm TB and ported intake manifold. On our cars the ported manifold was big power (relatively speaking). That, and you should look at gears. Engine work on something as complex as a VVT DOHC V6 is not easy considering the lack of investment and support. There are other, better options.

Ive thought of getting a trifecta tune once I apply a cold air intake. I would like to apply a 80 mm throttle body tho , and ported manifold.

How much potential power could be made from sleeving the cyclinders and boring them out?