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3032 Views 27 Replies 15 Participants Last post by  CTSV_510
Fellas,

Still over in no man's land.. After seeing the great rumble of some livernois stage 2 cnc ported heads it got me thinkin... i have always heard AFR is top of the line, and with that comes a hefty price tag... I found some AFR Mongoose 205cc ls6 heads for around 2k. Is it worth it? Would I be getting enough bang for my buck? Or should I be cheap and just port and polish my stock ls6 heads? and if I go either route, I'm assuming the only way to get noticeable gains is to get a better TB and intake so the engine takes bigger breathes, right? And a cam of course, I probably won't go bigger than a mild cam (and one that would work well with a maggie, as I'm still in the market for one... Any other suggestions? trying to load up on some goodies so I can have them all installed when I get back.. any input is appreciated
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This doesn't really answer to many of your questions but I talked to patriot and for $800 they will drop in bigger valves and cnc port your stock heads. It gets more expensive for springs and retainers but I already had them.

Personally I would go TFS or AFR. You wont go wrong with either head if you have the money but I dont see why an ported 243 would be bad
nice link darkman. That's a good read...and I'm not even after heads in the immediate future.
Rob, I suggested to Den_93 the other day when he stopped by with his car that, since he has the new Livernois heads and big cam, he consider a FAST 90 intake and 90 mm TB. He's already on it and is looking at some other intake (can't recall the name of it ... maybe he'll chime in here).

Anyway, if you decide to go the Maggie route, you may decide to stay with stock internals/heads/TB since it's so easy. If you decide to get heads/intake/cam/TB/etc, you probably will want to just stay NA (and not add a Maggie on top of it all. ). If you do go with some combination of both routes, you're going to have to get into the bottom of the motor with forged internals. I guess it depends on just how much $$$ you're limiting yourself to. :stirpot:
nice link darkman. That's a good read...and I'm not even after heads in the immediate future.
I guess we will need to work on making you want new heads sooner rather than later.
These are for sale locally....would these work on a V? http://denver.craigslist.org/pts/1083562968.html
Sorry if the question is dumb, I know nothing about this stuff :(
I was considering doing some heads and a cam on my maggied V, after a couple months when I will need more power. I talked with one very smart motor guy about this the other day. He said that a cam really wouldn't make much of a difference if you have a maggie. He said since you are forcing air into the motor with the maggie, a bigger cam would not be worth the extra $$$. I wanted to get your guys 2cents? Anyone running a cam/maggie setup? What kind of hp# gains did the cam give you?
thansk for the link darkman, that was a good read
These are for sale locally....would these work on a V? http://denver.craigslist.org/pts/1083562968.html
Sorry if the question is dumb, I know nothing about this stuff :(
Those would work fine on an LS6 but you need to make sure they are for a standard bore (3.89" something or other) and see what the runner length is. To big a runner can hurt performance on a stock cube engine. Generally speaking, the bigger intake runner likes more cubes but it depends on if its a track car or something you drive on the street. Since its for a V, I would opt for like a 215cc or maybe a 225cc. Some guys run a 205cc runner and have great success for daily drivers. Those heads flow well also.
I was considering doing some heads and a cam on my maggied V, after a couple months when I will need more power. I talked with one very smart motor guy about this the other day. He said that a cam really wouldn't make much of a difference if you have a maggie. He said since you are forcing air into the motor with the maggie, a bigger cam would not be worth the extra $$$. I wanted to get your guys 2cents? Anyone running a cam/maggie setup? What kind of hp# gains did the cam give you?
Staying with a 2.8" pulley and getting a more effiicient H/C setup might help some. Maybe +20-30 hp? (<-- I'm guessing.) I'm not sure if anyone here has done that. I'd think you'd have to have headers to take advantage of the better flow characteristics. A 2.6" pulley would be an even cheaper route than H/C and may yield even more HP increase. An 8-rib/larger crank pulley would also help, but then you're talking maybe more cost than H/C.

The thing is, as soon as you open up one part of the airflow path, something else becomes the new bottleneck. Predicting that accurately is the hard part.
I was considering doing some heads and a cam on my maggied V, after a couple months when I will need more power. I talked with one very smart motor guy about this the other day. He said that a cam really wouldn't make much of a difference if you have a maggie. He said since you are forcing air into the motor with the maggie, a bigger cam would not be worth the extra $$$. I wanted to get your guys 2cents? Anyone running a cam/maggie setup? What kind of hp# gains did the cam give you?
I really really really hate to threadjack here, but I have to momentarily.

Whoever this "one very smart motor guy" is, he is misinformed or mislearned or whatever you want to call it. Here is a 53rwhp/34rwtq gain from adding just a camshaft to a maggied LS2 TBSS. specs are 215/228 .630/.588 116



I am not saying this is representative of what you should expect from a cam swap on your maggied motor, just that you may want to get your future advice elsewhere.
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Those would work fine on an LS6 but you need to make sure they are for a standard bore (3.89" something or other) and see what the runner length is. To big a runner can hurt performance on a stock cube engine. Generally speaking, the bigger intake runner likes more cubes but it depends on if its a track car or something you drive on the street. Since its for a V, I would opt for like a 215cc or maybe a 225cc. Some guys run a 205cc runner and have great success for daily drivers. Those heads flow well also.
Just to clarify, those numbers you're quoting aren't runner length, they're intake port volume. Pretty much every head's intake runner is going to be the same length, but the size of the port is going to have an impact on intake charge velocity help determine how the heads perform. Too big an intake port on a mild engine can hurt performance.

I really really really hate to threadjack here, but I have to momentarily.

Whoever this "one very smart motor guy" is, he is misinformed or mislearned or whatever you want to call it. Here is a 53rwhp/34rwtq gain from adding just a camshaft to a maggied LS2 TBSS. specs are 215/228 .630/.588 116.

I am not saying this is representative of what you should expect from a cam swap on your maggied motor, just that you may want to get your future advice elsewhere.
I didn't have a graph to throw up to prove the point like 510, but I was going to say the same thing. The cam is the heart of the engine. Anyone that thinks swapping a stock cam for something more aggressive isn't worthwhile isn't giving useful advice.
My sources tell me that NASCAR engine builders routinely pay $20,000+ for a set of heads. Highest number I've seen is $40,000 for heads for a restrictor plate engine.
Just to clarify, those numbers you're quoting aren't runner length, they're intake port volume. Pretty much every head's intake runner is going to be the same length, but the size of the port is going to have an impact on intake charge velocity help determine how the heads perform. Too big an intake port on a mild engine can hurt performance.


I didn't have a graph to throw up to prove the point like 510, but I was going to say the same thing. The cam is the heart of the engine. Anyone that thinks swapping a stock cam for something more aggressive isn't worthwhile isn't giving useful advice.

Thats kind of what I meant but I had my head up my butt lol. I know runner length will be relatively the same on every head. You cant move the combustion chamber. As you stated, if the port flows more volume you have less velocity which can hurt your performance. Its just like running carb that is to big for an engine. People think bigger is better! Not always the case.

Sorry for any confusion.
When I saw this poast was from Rob and the thread title was "Heads", I thought I was going to see some dishonorable discharge type information in here.

But then I remembered that Rob is a stand up, honorable guy that has an insatiable desire to feed his V machine.

Rob, hope all is well on the other side of the world. You contact any of the shops near Shameburg for quotes on the work?
When I saw this poast was from Rob and the thread title was "Heads", I thought I was going to see some dishonorable discharge type information in here.

But then I remembered that Rob is a stand up, honorable guy that has an insatiable desire to feed his V machine.

Rob, hope all is well on the other side of the world. You contact any of the shops near Shameburg for quotes on the work?
lol, ya well those pictures won't be coming online any time soon, i've shot out a few emails, definitely not going back to Speed Inc. :rant2: just wasn't sure if 205cc would be the best for the ls6, i've read that most guys go with 215cc heads... not sure on how big of a difference there is, etc.
lol, ya well those pictures won't be coming online any time soon, i've shot out a few emails, definitely not going back to Speed Inc. :rant2: just wasn't sure if 205cc would be the best for the ls6, i've read that most guys go with 215cc heads... not sure on how big of a difference there is, etc.
You are close enough that I would go to EPP or Pro Dyno Tech to get all the work done. You could even look into Lingenfelter as they are in Indiana too.

When do you get back Rob? We should meet up at Autobahn and use some of my Dad's partner's guest passes!
Rob, with all the money your putting into your V, have you thought about just using that money for a down payment on an 09?
With everything your trying to do, you'll probably just get to what the V2 is pushing. Nevermind the new interior and wheelhop-less launches :bouncy:
Keep in mind, there's only so much power you can put into this motor without hurting it, or other parts of the car.

Tony
I know that when it comes to NA motors you have to be careful in street applications not to get heads that flow too much volume or cams with too much lift / or duration because the result can be no low-to-midrange torque. It seems to me however, that in the case of forced induction street applications you may be able to actually use higher flow heads and/or higher lift/longer duration camshafts because FI motors are so low/midrange torque intensive anyway. Stated differently, the excessive flow volume created by biggers head/cam combinations in NA motors moves too slowly to be efficient at low rpm but with forced induction that probelm may not occur.
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