What heads for a N/A 408ci?
What heads for a N/A 408ci? Never done a N/A A408 before..
What heads would you run?
Milled stock ls3s? How bad do ls3 heads shroud the valves on a 408?
Manual 3100 lb car with IRS
All motor setup to roll race and just be fun on the street
Heres the combo
6.0 block
4.030 bore Wiseco -3cc flat tops
4" stroke
Summit Stage 5 Cam
247/255, 113.5 + 2, 625/.615
Either a
TSP SR-3 intake
or a FAST 102
What heads would you run?
Milled stock ls3s? How bad do ls3 heads shroud the valves on a 408?
Manual 3100 lb car with IRS
All motor setup to roll race and just be fun on the street
Heres the combo
6.0 block
4.030 bore Wiseco -3cc flat tops
4" stroke
Summit Stage 5 Cam
247/255, 113.5 + 2, 625/.615
Either a
TSP SR-3 intake
or a FAST 102
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Joined: Oct 2020
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Ask Eric Roycroft... I'd say Shrouding isn't Even a Major Concern. It's a LS 1 tech BS conversation to Try and Sell heads.
I maybe Wrong ....but I doubt it. Ask A porter Who's not Trying to Sell u something 4 Facts!
👍
Btw it's Fake News. How do I know? Dart Ls3 Heads @ 280cc 👈 😂🤣 on a Darn Ls2 402 which Has Nothing different than A Factory Ls3 head.
Project Escalation
I maybe Wrong ....but I doubt it. Ask A porter Who's not Trying to Sell u something 4 Facts!
👍
Btw it's Fake News. How do I know? Dart Ls3 Heads @ 280cc 👈 😂🤣 on a Darn Ls2 402 which Has Nothing different than A Factory Ls3 head.
Project Escalation
Last edited by Corona; Jun 1, 2021 at 01:50 PM.
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You asked a loaded question BTW.
How does anyone Who Doesn't Port Heads know The Facts on the Question asked?
😏😉 I've asked Every Question Known to Man about anything dealing with a LS HEAD. 🤫
ER will say if it's the Exhaust it's not a Problem Some guys move the Dowels and go with a Smaller Valve.
If you wanna get a aftermarket head Just get 1 but the Shrouding thought isn't Worth the Time nor the idea of Finding X amount of HP. If you wanna Move them Move "Em, on the Dowels.
How does anyone Who Doesn't Port Heads know The Facts on the Question asked?
😏😉 I've asked Every Question Known to Man about anything dealing with a LS HEAD. 🤫
ER will say if it's the Exhaust it's not a Problem Some guys move the Dowels and go with a Smaller Valve.
If you wanna get a aftermarket head Just get 1 but the Shrouding thought isn't Worth the Time nor the idea of Finding X amount of HP. If you wanna Move them Move "Em, on the Dowels.
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My engine is a 402 and I went with Mamo 235 heads, should make great power and have plenty under the curve. Not saying LS3s won't just the direction I decided to go. Cam is 243/249 .675/.675 114+3 so fairly aggressive. Compression works out to 11.8:1 with DCR in the 8.3s for a pump gas friendly build. Tony estimated in the 630-650hp range, but I'm also doing a Meziere 329 and GZ Vacuum pump.
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Verdad Gallardo My engine is a 402 and I went with Mamo 235 heads, should make great power and have plenty under the curve. Not saying LS3s won't just the direction I decided to go. Cam is 243/249 .675/.675 114+3 so fairly aggressive. Compression works out to 11.8:1 with DCR in the 8.3s for a pump gas friendly build. Tony estimated in the 630-650hp range, but I'm also doing a Meziere 329 and GZ Vacuum pump.
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No Love Nor Loyalty when Talking HP... Just Straight Shooting. 🤔 Summit can Ponder about it Afterwards When purchased With LIFT. 👍
no Love Loss or added. If you get Special treatment on Cost that's A Whole Different Story.
Last edited by Corona; Jun 1, 2021 at 03:23 PM.
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From: ELSA, South TEXAS (956) 802-7700
Don't worry about heads. They'll be fine. I think the duration is a bit much for a fun street car. Seems more for a max effort build. The 625 lift is good especially with trunion upgraded only stock rocker arms. I would go with fast for fun street car and tsp sr3 for max effort. I guess perhaps reevaluate between fun street car and max effort... Just my 2 cents.
$200 cam vs a $490 Cam to gain what? Maybe 10 hp up top and less spring life. Im good .
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👍 Good Springs will last ... But + on cost
Cheaper Cam wins. Keep it Cheap all the way Through. Hp is and will be there with More Cubes your just not Trying to Get after it. Keep it Simple and Fun... 600 hp isn't Asking Much 625 isn't Either.
Out think the 408 Cathedral head Test?
Compare your *cam* and build to the one used in the test. My thoughts are Skip asking just Find something Similar to Set the Mark. It's a Basic Private Fight your Doing. And What You may Want.
Easy Guess Estimate of what you may have Before hand. 👇 Only a cam Difference?
https://www.hotrod.com/articles/hrdp...der-head-test/
Cheaper Cam wins. Keep it Cheap all the way Through. Hp is and will be there with More Cubes your just not Trying to Get after it. Keep it Simple and Fun... 600 hp isn't Asking Much 625 isn't Either.
Out think the 408 Cathedral head Test?
Compare your *cam* and build to the one used in the test. My thoughts are Skip asking just Find something Similar to Set the Mark. It's a Basic Private Fight your Doing. And What You may Want.
Easy Guess Estimate of what you may have Before hand. 👇 Only a cam Difference?
https://www.hotrod.com/articles/hrdp...der-head-test/
Last edited by Corona; Jun 1, 2021 at 08:40 PM.
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From: Coast of San Mateo County Between Pacifica & HMB
My .02 with that cam (+8 Exhaust Split) and FAST Intake.....
AFR LS3 with hollow intake, solid exhaust valves (100g/99g).
260 CC outflows 280 DART EVERYWHERE
Intake & EXHAUST up to .700"
AFR LS3 with hollow intake, solid exhaust valves (100g/99g).
260 CC outflows 280 DART EVERYWHERE
Intake & EXHAUST up to .700"
