Magnuson Ports
Thread Starter
Pro
Joined: Oct 2011
Posts: 552
Likes: 3
From: Toronto Ontario
Pro
Joined: Dec 2010
Posts: 554
Likes: 1
From: Davie Florida
I have LS3 heads also and my Maggie came the same way. When I called Magnuson to ask about pulley sizes and the rear cog overdrive he asked me how much power I was planning on pushing. So I explained around 750ish.
He explained to me that since I bought an LS3 kit it has triangle ports unlike the LS7 kit to actually restrict airflow, and if I wanted to push more than 650 to the ground I would have to port the Maggie manifold to match the LS3 head ports.
He said no matter how much boost I through at it it wouldn't make more than 650 do to the restriction the triangle ports cause.
So here I am with a brand new blower taking it apart and brought the lower half to a machine shop and had it ported.
This is straight from one of the tech guys at Maggie not my words. I hope this helps answering your question and guiding you in the right direction for your build.
He explained to me that since I bought an LS3 kit it has triangle ports unlike the LS7 kit to actually restrict airflow, and if I wanted to push more than 650 to the ground I would have to port the Maggie manifold to match the LS3 head ports.
He said no matter how much boost I through at it it wouldn't make more than 650 do to the restriction the triangle ports cause.
So here I am with a brand new blower taking it apart and brought the lower half to a machine shop and had it ported.
This is straight from one of the tech guys at Maggie not my words. I hope this helps answering your question and guiding you in the right direction for your build.
Thread Starter
Pro
Joined: Oct 2011
Posts: 552
Likes: 3
From: Toronto Ontario
I have LS3 heads also and my Maggie came the same way. When I called Magnuson to ask about pulley sizes and the rear cog overdrive he asked me how much power I was planning on pushing. So I explained around 750ish.
He explained to me that since I bought an LS3 kit it has triangle ports unlike the LS7 kit to actually restrict airflow, and if I wanted to push more than 650 to the ground I would have to port the Maggie manifold to match the LS3 head ports.
He said no matter how much boost I through at it it wouldn't make more than 650 do to the restriction the triangle ports cause.
So here I am with a brand new blower taking it apart and brought the lower half to a machine shop and had it ported.
This is straight from one of the tech guys at Maggie not my words. I hope this helps answering your question and guiding you in the right direction for your build.
He explained to me that since I bought an LS3 kit it has triangle ports unlike the LS7 kit to actually restrict airflow, and if I wanted to push more than 650 to the ground I would have to port the Maggie manifold to match the LS3 head ports.
He said no matter how much boost I through at it it wouldn't make more than 650 do to the restriction the triangle ports cause.
So here I am with a brand new blower taking it apart and brought the lower half to a machine shop and had it ported.
This is straight from one of the tech guys at Maggie not my words. I hope this helps answering your question and guiding you in the right direction for your build.
I am not going for more than 600 now but figure I may as well match them up while its off..
Did you think the restriction is necessary with lower boost?
Did you get my PM? im gonna Pal you ASAP
Pro
Joined: Dec 2010
Posts: 554
Likes: 1
From: Davie Florida
From what Maggie explained to me the ports were made that way so as to not over power a stock LS3. Now on a built LS3 there's no issue. But then again I know guys who are pushing more than 650 on stock bottom ends, but they are using centris not PD's. The sudden shock of all the instant HP from a PD may grenade a stock LS3 were as a centri may not.
As far as the restriction being necessary, I don't think so because the tech from Maggie only stated it was put in place to reduce the max achievable HP. You can alway adjust boost by changing the pulleys if you needed to.
And yes I got your email, thanks!
As far as the restriction being necessary, I don't think so because the tech from Maggie only stated it was put in place to reduce the max achievable HP. You can alway adjust boost by changing the pulleys if you needed to.
And yes I got your email, thanks!
Thread Starter
Pro
Joined: Oct 2011
Posts: 552
Likes: 3
From: Toronto Ontario
From what Maggie explained to me the ports were made that way so as to not over power a stock LS3. Now on a built LS3 there's no issue. But then again I know guys who are pushing more than 650 on stock bottom ends, but they are using centris not PD's. The sudden shock of all the instant HP from a PD may grenade a stock LS3 were as a centri may not.
As far as the restriction being necessary, I don't think so because the tech from Maggie only stated it was put in place to reduce the max achievable HP. You can alway adjust boost by changing the pulleys if you needed to.
And yes I got your email, thanks!
As far as the restriction being necessary, I don't think so because the tech from Maggie only stated it was put in place to reduce the max achievable HP. You can alway adjust boost by changing the pulleys if you needed to.
And yes I got your email, thanks!
Did you have to do anything to boost fuel pressure/volume?
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Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
I've always heard the port mismatch was more to equalize flow and reduce emissions. That limiting boost explanation may be Magnuson's official line....but I don't buy it. My new Heartbeat's ports look just like an LS3's intake ports. I wonder why they don't limit boost on that one. I have a catty port TVS2300 on my truck and the ports are pretty well matched on that one too.
My old Vette has been running at around 650rwhp for the better part of 5 years now. It's not too hard to get them up around 700 before running into belt slip, etc. They'll go higher, but that's where the dollar spent per hp gained equation gets ugly in my eyes. More ribs on the pulleys and more heat to deal with. Porting the manifold and maybe a spacer/insulating plate would help if wanting more than 700.
My old Vette has been running at around 650rwhp for the better part of 5 years now. It's not too hard to get them up around 700 before running into belt slip, etc. They'll go higher, but that's where the dollar spent per hp gained equation gets ugly in my eyes. More ribs on the pulleys and more heat to deal with. Porting the manifold and maybe a spacer/insulating plate would help if wanting more than 700.
Le Mans Master
Joined: Apr 2013
Posts: 5,376
Likes: 1,118
What a crock! If they wanted to limit output, why not just sell it with a bigger upper pulley to limit boost and let folks pulley down at their own risk??
Maybe they just want to make sure that their new overpriced Heartbeat isn't outpaced by their old TVS???
Maybe they just want to make sure that their new overpriced Heartbeat isn't outpaced by their old TVS???
Pro
Joined: Dec 2010
Posts: 554
Likes: 1
From: Davie Florida
I agree with you totally!! When he explained that to me it really didn't make any sense, especially when the LS7 kit isn't like that and it only makes like 5psi out of the box. So the port design for the LS3 really doesn't make sense especially when he instructed that I have them ported. Your probably correct about them not wanting it to produce the same as the heartbeat so they can promote there new product.
Burning Brakes
Joined: Jul 2006
Posts: 824
Likes: 3
From: Houston, Tx.....'05 Corvette M6 LS3 Magnuson Heartbeat
.....wait...not so fast. The TVS 2300 requires an aftermarket hood & paint (~$1,200-1,500). You have to consider that cost as a true $$$ comparison between both kits, right? Most (new) TVS 2300 kits sell for ~$7,500 + the additional expense for a new hood/paint = ~$9k. I paid slightly more for the price of a new LS3 TVS 2300 (under $8k) for my LS3 Heartbeat making ~700 rwhp. Maybe due to the ports???
Lets face it....most centri guys would say, "BOTH kits are overpriced and UNDER powered!"
Here's a pic of my Heartbeat ports prior to install....They are both awesome kits. Can't wait to see the results of the ported manifolds. Keep us posted!
Mike
Melting Slicks
Joined: Mar 2007
Posts: 2,391
Likes: 23
From: Santa Barbara CA
I'd have to agree that the design of the old jackshaft TVS2300 manifold wasn't some premeditated conspiracy to make their (likely unplanned at the time) future blower design look better.
I know they did a lot of R&D to make the Heartbeat as efficient as possible. Making sure the intake manifold can flow as much as the heads can take is part of that, I'm sure.
I know they did a lot of R&D to make the Heartbeat as efficient as possible. Making sure the intake manifold can flow as much as the heads can take is part of that, I'm sure.
Le Mans Master
Joined: Apr 2013
Posts: 5,376
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Apologies for my earlier sudden outburst. It's just that if I put myself in the OPs shoes, I would be really p!ssed discovering that after buying a new blower. I still can't comprehend why they would build a blower that is custom made for a specific head with mismatched intake ports, just to limit power output? The only time I've seen that is back in the day when some folks used to put oval port BBC 6-71 roots blowers on rectangular port heads. It didn't make any sense to me then either, but I guess it's better that using a blower with bigger ports than the head.
And don't get me wrong, I really like the Heartbeat and having been considering buying one myself ever since I first saw it on here (I'm waiting until old motorhead gets his installed and tuned). However, I still feel it is a bit overpriced, especially compared to the E-force.
But, Mike, you are right that you have to factor in the cost of a new hood with the TVS. In light of that, with no intended offense to the OP, I can't see why anyone would want to buy a regular TVS now, if you have to buy a hood AND port the manifold?
BTW: where did you find your Heartbeat for under $8,000? Every one that I've seen advertised has been well north of $8K??
And don't get me wrong, I really like the Heartbeat and having been considering buying one myself ever since I first saw it on here (I'm waiting until old motorhead gets his installed and tuned). However, I still feel it is a bit overpriced, especially compared to the E-force.
But, Mike, you are right that you have to factor in the cost of a new hood with the TVS. In light of that, with no intended offense to the OP, I can't see why anyone would want to buy a regular TVS now, if you have to buy a hood AND port the manifold?
BTW: where did you find your Heartbeat for under $8,000? Every one that I've seen advertised has been well north of $8K??
Le Mans Master
Joined: Dec 2005
Posts: 7,002
Likes: 1,687
From: Southeast TX
Here's an interesting thread about port matching the LS3 head to the Maggie TVS from the Camaro 5 board.
http://www.camaro5.com/forums/showthread.php?t=340672
http://www.camaro5.com/forums/showthread.php?t=340672
Pro
Joined: Feb 2003
Posts: 745
Likes: 136
From: Detroit MI
The LS3 combustion system is very sensitive to misfire at light load, especially when port velocity is very low and in-cylinder mixing isn't all that great. If you chop off a bunch of the runner length (as is done with many positive displacement compressor designs), then the problem gets noticeably worse. Blocking off part of the port raises port velocity at idle and light load, greatly improving engine roughness and reducing misfire. The thought here is that the compressor can still push through the restriction up top well enough to make power, while having an improved combustion quality at lighter loads.
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
Melting Slicks
Joined: Mar 2007
Posts: 2,391
Likes: 23
From: Santa Barbara CA
Just as an FYI, I paid $6800 for my dry-sump Heartbeat system. That was a pretty damn good deal, but they can be had for quite a bit less than retail if you know where to look and the time is right.
Melting Slicks
Joined: Mar 2007
Posts: 2,391
Likes: 23
From: Santa Barbara CA
The LS3 combustion system is very sensitive to misfire at light load, especially when port velocity is very low and in-cylinder mixing isn't all that great. If you chop off a bunch of the runner length (as is done with many positive displacement compressor designs), then the problem gets noticeably worse. Blocking off part of the port raises port velocity at idle and light load, greatly improving engine roughness and reducing misfire. The thought here is that the compressor can still push through the restriction up top well enough to make power, while having an improved combustion quality at lighter loads.
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
Thread Starter
Pro
Joined: Oct 2011
Posts: 552
Likes: 3
From: Toronto Ontario
The LS3 combustion system is very sensitive to misfire at light load, especially when port velocity is very low and in-cylinder mixing isn't all that great. If you chop off a bunch of the runner length (as is done with many positive displacement compressor designs), then the problem gets noticeably worse. Blocking off part of the port raises port velocity at idle and light load, greatly improving engine roughness and reducing misfire. The thought here is that the compressor can still push through the restriction up top well enough to make power, while having an improved combustion quality at lighter loads.
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
If you were to port match a completely stock LS3/magnacharger combo, it is very likely that you would experience a significant decrease in driveability and stability at light load and idle. The effect goes away as you run more boost (high blower speed, more losses, higher load required to turn the blower at idle) or a larger camshaft (again, higher load required to find a stable idle).
Pro
Joined: Dec 2010
Posts: 554
Likes: 1
From: Davie Florida
Never really said it was a power limiting strategy. That was one theory, maybe a bad one lol, but that's all it was IMO. But the fact doesn't change that Magnuson themselves stated to push over 650rwhp on a mustang dyno not a dynojet, which is a huge differance, I would need to port the manifold. Hopefully it will all work out great for me, it's a pretty big build with a stroker motor and big cam so the issue needing the turbulence created by the triangular port design at low idle won't be an issue for me. Keep your fingers crossed lol. Car is at the shop and prob won't be dynoed till end of next week. I'll post numbers up as soon as I get them.
PS: this thread so for has been great and the saying goes, you learn something new everyday. Now I know why they designed the ports that way.
Also I love the new heartbeat and was thinking about it but the deal I got on a brand new still in the box unopened LS3 Maggie TVS2300 I couldn't pass up. $5500 shipped to my door!! I did the install myself and already had the hood so it worked out for me and I saved a TON of $$$
PS: this thread so for has been great and the saying goes, you learn something new everyday. Now I know why they designed the ports that way.
Also I love the new heartbeat and was thinking about it but the deal I got on a brand new still in the box unopened LS3 Maggie TVS2300 I couldn't pass up. $5500 shipped to my door!! I did the install myself and already had the hood so it worked out for me and I saved a TON of $$$