TFS 215: leave alone or mill?
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TFS 215: leave alone or mill? I'm curious: if one were to purchase a set of TFS 215 heads for an otherwise stock LS1 (2001 SS, with long tubes), what REAL benefit would there be milling the heads down to say, 61cc?
I know there's power to be had, but how much? How about torque?
Is it negligible or significant?
Would leaving the heads as-is leave doors open for future upgrades (bigger cam, FI, etc)?
And as an aside: what benefit is there from purchasing TFS heads from TEA vs a big box store (like summit?), assuming you're buying as is?
I know there's power to be had, but how much? How about torque?
Is it negligible or significant?
Would leaving the heads as-is leave doors open for future upgrades (bigger cam, FI, etc)?
And as an aside: what benefit is there from purchasing TFS heads from TEA vs a big box store (like summit?), assuming you're buying as is?
There is currently a set of TFS 205s for sale in the classifieds that already have 58 cc chambers, flow about 300 cfm, and with the powdered metal valve guides they are stock rocker compatible.
More compression gains power and torque everywhere in the power band. How much really depends on the setup and how much compression you are gaining. Roughly it's 3-4% per every full point increase.
As far as future upgrades in the FI department, yes it helps but at that point you really have to see what comp ratio you have and which is best for your goals.
As far as future upgrades in the FI department, yes it helps but at that point you really have to see what comp ratio you have and which is best for your goals.
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More compression gains power and torque everywhere in the power band. How much really depends on the setup and how much compression you are gaining. Roughly it's 3-4% per every full point increase.
As far as future upgrades in the FI department, yes it helps but at that point you really have to see what comp ratio you have and which is best for your goals.
As far as future upgrades in the FI department, yes it helps but at that point you really have to see what comp ratio you have and which is best for your goals.
I'm going to guesstimate that adding a TFS 215 heads and mild cam I'd be adding about 100rwhp. By going with the 215's stock, I'm bumping compression to roughly 10.5.
If I mill those same heads to 61cc, I'd be bumping compression up to 11. So using that 3-4 rule, I'd be bumping up 1.5-2%. Would that mean milling would only gain me 1.5-2hp? Or would I be looking at overall HP, meaning I'd gain 1.5-2% of 430, meaning about 12hp?
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Not necessarily, but the thought has crossed my mind. So I'd hate to spend $6k on heads/cam only to decide in 3 years that I want to boost it (I think most would agree boosting a daily driver that gets 11-1CR is a disaster waiting to happen).
But, if I can meet my goals (a really fun, reliable daily driver, with plenty of down-low power), by simply milling the heads now, then I think I'd be happy.
I mean, the 20 year plan includes paying off the student loans (5 years of that), replacing the truck when the loans are gone (she'll be 10 years old then), and then add a nice vette convertible to the mix (assuming they're still building fun V8's in 15 years)... But ya gotta have SOME fun in the meantime!
But, if I can meet my goals (a really fun, reliable daily driver, with plenty of down-low power), by simply milling the heads now, then I think I'd be happy.
I mean, the 20 year plan includes paying off the student loans (5 years of that), replacing the truck when the loans are gone (she'll be 10 years old then), and then add a nice vette convertible to the mix (assuming they're still building fun V8's in 15 years)... But ya gotta have SOME fun in the meantime!
Static compression is only the numerical calculation
dynamic compression is truly what the engine operates on. This is determined by the camshaft selected.
A 9 to one engine with a small cam can have more cranking compression than an 11 to one with a giant cam.
With all things being equal, numerical compression is a law of diminishing returns. In other words from 7 to 9 gains approx. 11% power; 9 to 11 it drops to around 7%; and 11 to 13 it's only about 2%...that's assuming proper octane fuel and no detonation. In your case a jump from 10.2 to 11 range is at most worth 10-12 horse and foot pounds of torque.
Leaving the heads at 64cc and running a Cometic .040" gasket will get you darn close to 11 without milling
dynamic compression is truly what the engine operates on. This is determined by the camshaft selected.
A 9 to one engine with a small cam can have more cranking compression than an 11 to one with a giant cam.
With all things being equal, numerical compression is a law of diminishing returns. In other words from 7 to 9 gains approx. 11% power; 9 to 11 it drops to around 7%; and 11 to 13 it's only about 2%...that's assuming proper octane fuel and no detonation. In your case a jump from 10.2 to 11 range is at most worth 10-12 horse and foot pounds of torque.
Leaving the heads at 64cc and running a Cometic .040" gasket will get you darn close to 11 without milling
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Static compression is only the numerical calculation
dynamic compression is truly what the engine operates on. This is determined by the camshaft selected.
A 9 to one engine with a small cam can have more cranking compression than an 11 to one with a giant cam.
With all things being equal, numerical compression is a law of diminishing returns. In other words from 7 to 9 gains approx. 11% power; 9 to 11 it drops to around 7%; and 11 to 13 it's only about 2%...that's assuming proper octane fuel and no detonation. In your case a jump from 10.2 to 11 range is at most worth 10-12 horse and foot pounds of torque.
Leaving the heads at 64cc and running a Cometic .040" gasket will get you darn close to 11 without milling
dynamic compression is truly what the engine operates on. This is determined by the camshaft selected.
A 9 to one engine with a small cam can have more cranking compression than an 11 to one with a giant cam.
With all things being equal, numerical compression is a law of diminishing returns. In other words from 7 to 9 gains approx. 11% power; 9 to 11 it drops to around 7%; and 11 to 13 it's only about 2%...that's assuming proper octane fuel and no detonation. In your case a jump from 10.2 to 11 range is at most worth 10-12 horse and foot pounds of torque.
Leaving the heads at 64cc and running a Cometic .040" gasket will get you darn close to 11 without milling
I've reached out to several companies in trying to get a kit put together (TEA, who recommends the TFS 515 top end kit as a starting point, vengeance racing, who takes a TEA modified TFS 215 head, adds PM sleeves to work with upgraded factory rockers and one of their VRX cams, Tony Mamo, and Don at Slowhawk (a very well known tuner up the road), who takes the TFS 215 and mates it to one of his own cams).
The problem is each guy has their own way, and their own cam. I'm leaning towards the TFS kit, only because in my head, I feel that they must have worked all the details into it.
But then again, it's hard to argue with such reputable tuners!
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Verdad Gallardo Yeah I agree that the more you know the more confused you can get.
Here's the deal though; the Trick Flow head is such a quality product that you would still make decent power with a mediocre cam. The TF kit probably comes with a real mild camshaft that is valve spring friendly. Most custom cams are more aggressive (faster ramp rate) and require more frequent spring checks. Most people are changing their **** up by 15-20K anyways so it's rarely an issue.
IIWY I'd get the heads with the PM guides and run either a TICK street heat stg. 1 V2 or the Brian Tooley stage two.
Here's the deal though; the Trick Flow head is such a quality product that you would still make decent power with a mediocre cam. The TF kit probably comes with a real mild camshaft that is valve spring friendly. Most custom cams are more aggressive (faster ramp rate) and require more frequent spring checks. Most people are changing their **** up by 15-20K anyways so it's rarely an issue.
IIWY I'd get the heads with the PM guides and run either a TICK street heat stg. 1 V2 or the Brian Tooley stage two.
Last edited by A.R. Shale Targa; Jan 25, 2015 at 08:34 AM.
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Yeah I agree that the more you know the more confused you can get.
Here's the deal though; the Trick Flow head is such a quality product that you would still make decent power with a mediocre cam. The TF kit probably comes with a real mild camshaft that is valve spring friendly. Most custom cams are more aggressive (faster ramp rate) and require more frequent spring checks. Most people are changing their **** up by 15-20K anyways so it's rarely an issue.
IIWY I'd get the heads with the PM guides and run either a TICK street heat stg. 2 V2 or the Brian Tooley stage two.
Here's the deal though; the Trick Flow head is such a quality product that you would still make decent power with a mediocre cam. The TF kit probably comes with a real mild camshaft that is valve spring friendly. Most custom cams are more aggressive (faster ramp rate) and require more frequent spring checks. Most people are changing their **** up by 15-20K anyways so it's rarely an issue.
IIWY I'd get the heads with the PM guides and run either a TICK street heat stg. 2 V2 or the Brian Tooley stage two.
That 3-4% would be overall? Or added? For example: My car dyno'd 329rwhp with KN FIPK, ARH 1 3/4 race headers (ORY), and Corsa catback setup.