Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Tulip valve????

Thread Tools
 
Search this Thread
 
Old Aug 11, 2003 | 04:57 PM
  #1  
bodhi's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Jun 2002
Posts: 563
Likes: 0
From: Deer Park
Default Tulip valve????

I just spoke with Brian @ TEA- very nice, knowledgeable and helpful. During my chat with him, I told him that I was interested in a 5.3 StgII, 2.055-1.60, dual springs, Ti retainers and 11.5CR. He agreed with almost all of this except the CR and the exhaust valve size. He said that to reach that CR, I would have problems with PVC (which I expected), and the 1.60 exhaust valve was too big.
From what he said, the stock 1.55 valve will flow better due the 24 degree "tulip" back angle. Is this correct? He said that this was the best way to go and that there were no issues with the stock valve..
From what he told me, the Ferrea and Manley valves only come in like a 20? degree slope and the only ay to go above the 24 was to go titanium.
So what's the deal? will the 1.55 stock valve work better because of the shape or will the 1.60 Ferrea work better due to the size?

What kind of CR can I go with and not have any major PVC problems? He told me about flycutting the pistons myself with the Isky jig (and that he would loan it to me for free), but I don't think I'm gonna pull the motor to do the swap.
Reply
Old Aug 11, 2003 | 06:47 PM
  #2  
Phil99vette's Avatar
7 Second Club
iTrader: (11)
 
Joined: Jul 2002
Posts: 8,758
Likes: 9
From: Port Tobacco, MD
Default Re: Tulip valve????

You can run a thinner head gasket and pick up more compression than milling. Try a thin cometic gasket and 60cc chambers....should be more compression than you need.
Phillip
Reply
Old Aug 11, 2003 | 09:48 PM
  #3  
bodhi's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Jun 2002
Posts: 563
Likes: 0
From: Deer Park
Default Re: Tulip valve????

You can run a thinner head gasket and pick up more compression than milling. Try a thin cometic gasket and 60cc chambers....should be more compression than you need.
Phillip
Okay- BUT WTF is the deal Brian is talking about with the valve? Is he for real? Why would the stock valve flow better than a Ferrea?
Reply
Old Aug 12, 2003 | 08:17 AM
  #4  
mobius's Avatar
TECH Apprentice
 
Joined: Jan 2002
Posts: 347
Likes: 0
From: Orlando
Default Re: Tulip valve????

I have heard that the stock exhaust valves flow better...
Reply
Old Aug 12, 2003 | 08:25 AM
  #5  
Nine Ball's Avatar
LS1Tech Co-Founder
20 Year Member
iTrader: (38)
 
Joined: Nov 2001
Posts: 32,987
Likes: 58
From: Houston, TX
Default Re: Tulip valve????

A "tulip" shaped valve has a tapered stem diameter near the disk of the valve, where a standard shaped valve is more like a flat disk with a stem. The tulip is smoother in transition between the disk and stem.

The tulip valve will give a bit better numbers out of a 1.55 and 1.60 size difference. I learned this at one of the cult meetings we had :p
Reply
Old Aug 12, 2003 | 08:41 AM
  #6  
Colonel's Avatar
TECH Senior Member
 
Joined: Nov 2001
Posts: 9,246
Likes: 3
From: Troy, AL
Default Re: Tulip valve????

Reply
Old Aug 12, 2003 | 08:42 AM
  #7  
2001CamaroGuy's Avatar
TECH Veteran
iTrader: (6)
 
Joined: Feb 2002
Posts: 4,766
Likes: 0
From: Phoenix, AZ USA
Default Re: Tulip valve????

a tulip 1.55" would flow more than a "standard" 1.60....but you should be able to get tulip 1.60" valves so that would flow even better....
Reply
Old Aug 12, 2003 | 10:36 AM
  #8  
bodhi's Avatar
Thread Starter
TECH Enthusiast
 
Joined: Jun 2002
Posts: 563
Likes: 0
From: Deer Park
Default Re: Tulip valve????

A "tulip" shaped valve has a tapered stem diameter near the disk of the valve, where a standard shaped valve is more like a flat disk with a stem. The tulip is smoother in transition between the disk and stem.

The tulip valve will give a bit better numbers out of a 1.55 and 1.60 size difference. I learned this at one of the cult meetings we had :p

Thank you Tony. When I can afford the dues, I'll be there. Until then I'll come here for assistance.

I understand that the valve is tapered, but what's this deal about the stock valve working better than an aftermarket Ferrea (assumably tapered to the same degree as a stock 1.55" valve) 1.60"?
Brian brought this up and it doesn't seeem to make sense, but if it works- it works.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Aug 12, 2003 | 07:37 PM
  #9  
TEA Brent's Avatar
TECH Apprentice
 
Joined: Jun 2002
Posts: 321
Likes: 0
From: Bowling Green, KY
Default Re: Tulip valve????

The stock exhaust valve with its 20 or so degree back angle flows better than the Ferrea 1.55 (F6232) with its 12 degree back angle or the REV 1.57 with its whatever degree back angle and better than the Ferrea 1.60 (F6233) with its 12 degree back angle. The Ferrea 1.60 (F6234) with its 24 degree back angle will out flow the stock exhaust valve, but at the price of $100+ for the valves and $100 for the seat removal and reinstallation for the bigger valves. The kicker is we have seen LESS power with bigger exhuast valves on N/A engines. I know people don't believe some of this but we have tested it, and thats what we found, this is not our opinion. Thats why I brought up the fact that 900 HP Prostock Trucks have 2.200" intake valves and 1.58" exhaust, if you want to look at the sizing from a ratio aspect then the percentage of exhaust sizing to intake is 71.8%. If we use this math on our 2.05 intake valve then the exhaust valve would be 1.47 Things that make you go hummmmmmmm.
Hope this helps
Brian
Reply
Old Aug 12, 2003 | 07:42 PM
  #10  
needmoremoney's Avatar
TECH Regular
 
Joined: Mar 2003
Posts: 449
Likes: 0
From: W.P.B
Default Re: Tulip valve????

So bigger is not always better.
Reply
Old Aug 12, 2003 | 08:36 PM
  #11  
Cheatin' Chad's Avatar
TECH Addict
iTrader: (3)
 
Joined: Aug 2003
Posts: 2,561
Likes: 0
From: IL
Default Re: Tulip valve????

You can also swirl polish the valves and/or have them fully radiused for flow.Full radius for the most part works best on exhaust valves while a 3 or 5 angle tends to work best on intake valves.Engine builders for quite some time now have been using a 30* backcut on valves for a solid low lift(.100-.300) increase in flow.Differing degrees of backcuts will see differing amounts of increase at different lifts.Therefore the degree of backcut should be tailored to the camshaft being installed.
Intake to exhaust ratio(expressed in percentages here) is highly dependent on the type of motor you are building.While N/A motors tend to work best with an exhaust valve 65-75% of the intake.A supercharged(chemically or mechanically) motor will usually see the best numbers with an exhaust valve 70-85% of the intake. A higher C/R will often allow the use of a smaller exhaust valve.

BTW a "tulip" valve has a concave face making the valve lighter. This valve treatment does not affect flow at all to the best of my knowledge.
Reply




All times are GMT -5. The time now is 03:03 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE