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I have a 9.75:1 402 going in a 4,000lb Caprice with a 6L80 and 3.23 gears with a 27" tire. I'm targeting a max of 10psi.
With the extra displacement, I'm tempted to go with the GMPP CNC LS9 heads, and swap the springs for something with a higher lift. The cam I'm planning is a summit 8707. The specs are 226/238 .600/.600 113.
I think the extra displacement will make the bigger cam more driveable, but I'm curious if the larger stroke and displacement will make will make the bigger runners a non issue.
I'm definitely not an expert and I am curious to see what others have to say.
I also have an LSA on a 408 but I chose to run a stock 821/823 oem rectangle port head. I just don't know that there is enough if anything to gain by going to a CNC head with a blower that is this small on so many cubic inches when basic rectangle port head already does a decent job.
I have been interested recently in trying a different cam. Not that I hate the Summit Ghost cam but I truly do believe that it is just simply too small for a 408. I have been thinking about trying the Summit 8722R1 cam also listed as their current stage 3 twin turbo cam.
I have not seen the cam you are thinking about running and will have to check it out.
I'm definitely not an expert and I am curious to see what others have to say.
I also have an LSA on a 408 but I chose to run a stock 821/823 oem rectangle port head. I just don't know that there is enough if anything to gain by going to a CNC head with a blower that is this small on so many cubic inches when basic rectangle port head already does a decent job.
I have been interested recently in trying a different cam. Not that I hate the Summit Ghost cam but I truly do believe that it is just simply too small for a 408. I have been thinking about trying the Summit 8722R1 cam also listed as their current stage 3 twin turbo cam.
I have not seen the cam you are thinking about running and will have to check it out.
I had you in mind when I was thinking about the cam and what you had said about it being not quite big enough in your opinion.
The dilemma I have is that I need a set of heads, so looking at the available rectangular port options, new LS9s are available assembled for a little less than $700 each, eBay shows 821 and 823 heads going for roughly 400-425 each, but they'll have the heavy valves. The CNC LS9s are $999 each. A valve jobbed rectangular port would be another option too, with LS3 intake valves.
At that point the TSP brawler LS3s look appealing for $1837 for the pair.
I am a little hesitant about TSP anything after the big buyout and all the original owners and employees being gone. I don't know for sure though. Could be worrying about nothing.
That being said I don't see valve weight being a problem. We've turned this 408 to around 6500 several times on the dyno with zero complications even just using PAC 1219s. and really, unless you are planning on taking the car to the drag strip constantly it's not something I would worry about.
I can say my car never sees over maybe 4k on the street.
I had you in mind when I was thinking about the cam and what you had said about it being not quite big enough in your opinion.
The dilemma I have is that I need a set of heads, so looking at the available rectangular port options, new LS9s are available assembled for a little less than $700 each, eBay shows 821 and 823 heads going for roughly 400-425 each, but they'll have the heavy valves. The CNC LS9s are $999 each. A valve jobbed rectangular port would be another option too, with LS3 intake valves.
At that point the TSP brawler LS3s look appealing for $1837 for the pair.
I don't see why the 821/823's would be an issue with the stock valves, you won't be spinning it up to 7,500+rpm at 10lbs. unless you're using a big blower and why do that for 10lbs.
Should we start the pool now to determine how long that 10lb. limit lasts lol?
I don't want to come across as bashing in anyway, but a few people I know are not fans of TSP head castings.
The little I know about valves, I usually hear that lighter valves are better.
That said if I was really just going to run 10 psi I'd run stock 823s they are about $350 each around town.
IATs kinda climb with those blowers, buddies have spent some $ on interchillers and other a/w cooling systems.
I've noticed that about the IATs. I'm hoping that not trying to cram a bunch of boost in there, and get some serious airflow with a bigger cam, that heat gets kept to a minimum. We shall see. You're probably right about a good used set of cores.
Originally Posted by Mr. Black
I am a little hesitant about TSP anything after the big buyout and all the original owners and employees being gone. I don't know for sure though. Could be worrying about nothing.
That being said I don't see valve weight being a problem. We've turned this 408 to around 6500 several times on the dyno with zero complications even just using PAC 1219s. and really, unless you are planning on taking the car to the drag strip constantly it's not something I would worry about.
I can say my car never sees over maybe 4k on the street.
It might be nice to try some timed mile events, that's what made me thing about the lighter valves. The hollow stems are about half the weight, if I recall.
Originally Posted by The ******
I don't see why the 821/823's would be an issue with the stock valves, you won't be spinning it up to 7,500+rpm at 10lbs. unless you're using a big blower and why do that for 10lbs.
Should we start the pool now to determine how long that 10lb. limit lasts lol?
I'm hoping that cam limits my boost levels. Ya never know though...
I don't want to come across as bashing in anyway, but a few people I know are not fans of TSP head castings.
The little I know about valves, I usually hear that lighter valves are better.
That said if I was really just going to run 10 psi I'd run stock 823s they are about $350 each around town.
IATs kinda climb with those blowers, buddies have spent some $ on interchillers and other a/w cooling systems.
I'm curious what was it about the TSP heads that makes the people you know not be fans of them? Were there failures? The reason I ask is I'm in the market for heads that I plan to use on my next engine combo. TSP or spend the money on AFR or Trickflow heads.
I'm curious what was it about the TSP heads that makes the people you know not be fans of them? Were there failures? The reason I ask is I'm in the market for heads that I plan to use on my next engine combo. TSP or spend the money on AFR or Trickflow heads.
I have heard of recent issues with the valves popping the heads off. Of course that just destroys everything. I have had a couple sets of TSP LS3 heads go through my hands and they are def china castings. I would go with TFS, Brodix or Mast. Can't go wrong with any of them. I am leary of AFR these days too, because they are now pushing a china line and I am wondering just what base castings are what these days.
I have heard of recent issues with the valves popping the heads off. Of course that just destroys everything. I have had a couple sets of TSP LS3 heads go through my hands and they are def china castings. I would go with TFS, Brodix or Mast. Can't go wrong with any of them. I am leary of AFR these days too, because they are now pushing a china line and I am wondering just what base castings are what these days.
I've heard it all now...lol... the valves popped the heads clear off that engine...lol.
So, you are saying they are lying about where the heads are cast and machined? Let's stick to facts and not speculation. If you don't know then don't comment and don't make up lies.
I've heard it all now...lol... the valves popped the heads clear off that engine...lol.
So, you are saying they are lying about where the heads are cast and machined? Let's stick to facts and not speculation. If you don't know then don't comment and don't make up lies.
This is a snip from their website...
I think he's talking about the brawler heads that I originally asked about. They make no such claim.
It seems a few folks have ~260cc runner LS3 heads now. I'm guessing they're all cast in the same spot and then get finished how each company sees fit.
From my recollection, they are promaxx, afr, tsp, and mast. Maybe others as well.
I think he's talking about the brawler heads that I originally asked about. They make no such claim.
It seems a few folks have ~260cc runner LS3 heads now. I'm guessing they're all cast in the same spot and then get finished how each company sees fit.
From my recollection, they are promaxx, afr, tsp, and mast. Maybe others as well.
Aww. I see I wasn't looking at the brawler series. I'm looking at their cnc ported cathedral port heads cast in the usa for only a couple hundred more dollars.
Aww. I see I wasn't looking at the brawler series. I'm looking at their cnc ported cathedral port heads cast in the usa for only a couple hundred more dollars.
$873 more. But, like you said Made in USA, through and through.
I've heard it all now...lol... the valves popped the heads clear off that engine...lol.
So, you are saying they are lying about where the heads are cast and machined? Let's stick to facts and not speculation. If you don't know then don't comment and don't make up lies.
This is a snip from their website...
Ok, I'm not trying to make anything up, just going on experience. GNX7 told me of the valve issue a while back and I heard it verified through another source, so I considered it valid. As far as them being China based, its all the way. I spent considerable time researching base casting as I really try to run USA made stuff as much as possible. Honestly, I had set of TSP CNC LS3 w/ 2.185 valves in my hands and spent a bunch of time finding out what the base casting was. The port work is actually pretty nice, but the valve issue and cost involved to correct made me sell them. I have spent more time than I care to admit researching castings and trying to figure the source, not just for that but a lot of different heads. There is a massive amount of lies and bullshit out there. Believe me or not, idgaf, it's your money to blow.
If you believe everything you read on some company's website, that's your mistake to make.
As far as AFR, the longtime head of the company left not long after they were bought by private equity. You think the PE isn't trying to squeeze every dollar out? You think their Enforcer line is the only china casting? Come on, it's PE, they gave the whole run to China and said how much to copy, it's common sense. If they are really still making the base casting here then they must have a contract they have to fulfill. Let's see what happens over the next 5 years. Brodix, Mast and Trick Flow are still USA, real deal. All Pro too if you have the bucks. I have no idea why you are being argumentative, I'm just trying help, none of this is cheap. Just trying to offer info to spend the $$$ better, that's it.
Last edited by DualQuadDave; Apr 27, 2024 at 12:57 AM.
I have a 9.75:1 402 going in a 4,000lb Caprice with a 6L80 and 3.23 gears with a 27" tire. I'm targeting a max of 10psi.
With the extra displacement, I'm tempted to go with the GMPP CNC LS9 heads, and swap the springs for something with a higher lift. The cam I'm planning is a summit 8707. The specs are 226/238 .600/.600 113.
I think the extra displacement will make the bigger cam more driveable, but I'm curious if the larger stroke and displacement will make will make the bigger runners a non issue.
Thoughts?
Bang per buck, get the LS9 heads. 356-t6 base casting, Ti valves and spring it to your flavor. Run more cam. The blower is going to do all the work, you just need a good base head to hang in there. If anything, spend the $$ and port the **** out of the blower and run the biggest throttle body you can fit.
Ok, I'm not trying to make anything up, just going on experience. GNX7 told me of the valve issue a while back and I heard it verified through another source, so I considered it valid. As far as them being China based, its all the way. I spent considerable time researching base casting as I really try to run USA made stuff as much as possible. Honestly, I had set of TSP CNC LS3 w/ 2.185 valves in my hands and spent a bunch of time finding out what the base casting was. The port work is actually pretty nice, but the valve issue and cost involved to correct made me sell them. I have spent more time than I care to admit researching castings and trying to figure the source, not just for that but a lot of different heads. There is a massive amount of lies and bullshit out there. Believe me or not, idgaf, it's your money to blow.
If you believe everything you read on some company's website, that's your mistake to make.
As far as AFR, the longtime head of the company left not long after they were bought by private equity. You think the PE isn't trying to squeeze every dollar out? You think their Enforcer line is the only china casting? Come on, it's PE, they gave the whole run to China and said how much to copy, it's common sense. If they are really still making the base casting here then they must have a contract they have to fulfill. Let's see what happens over the next 5 years. Brodix, Mast and Trick Flow are still USA, real deal. All Pro too if you have the bucks. I have no idea why you are being argumentative, I'm just trying help, none of this is cheap. Just trying to offer info to spend the $$$ better, that's it.
Not trying to be argumentative just looking for facts. Too many people repeat things they heard but have never actually experienced. In the facts don't matter world we live in I still do the best I can to seek the truth.
Honestly I reread your post and I mistakenly thought when you said "valves popping the heads off" that the valves were causing the heads themselves to pop off and I was like whoa this guy is way out there with his claims. I now understand you meant the head of the valve popping off.
What about the casting of the head itself they are claiming that is cast in the USA? I'm not sure they claimed anything about the valves.
Basically I'm in a spot with a stock crank ls3 block with stock cathedral port heads running 20 psi and I'm thinking about going to a bigger blower and better engine combo. I prefer to move on from an engine while it's still good and useable rather than just destroy it knowing I'm going to be pushing it beyond it's limits soon.
I don't need the best flowing heads, but I do want additional strength and valves/springs that can hold up to high boost levels.
If I were to ping everyone I know know in the LS boosted universe and asked them to vote in an anonymous survey, I think the results would look something like this, most preferred to least:
Mast
Brodix
TFS
AFR
TSP
Frankenstein M311 might get votes too. I think a few companies sell the same casting but with proprietary porting (TKM).
If I were to ping everyone I know know in the LS boosted universe and asked them to vote in an anonymous survey, I think the results would look something like this, most preferred to least:
Mast
Brodix
TFS
AFR
TSP
Frankenstein M311 might get votes too. I think a few companies sell the same casting but with proprietary porting (TKM).
TFS are notably cheaper than Mast.
I will not use frankenstein, personally seen a friend have nothing but troubles with them. There was an issue with a guide when he first got them before even using them, then he tuliped the valves right away. After getting the valves replaced it then cracked a head and hydrolocked his dart block 427 on the big end of the 1/8th at high rpm. Destroyed everything.
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Head selection for a 402 with LSA 
