LargePort Head... whats needed for safe 450hp max...

limbo118118

limbo118118

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on a LP head, (AGU) whats needed to make it safe at running around 450bhp max.

ino of :-

- exhaust vavles
-guides
-stem seals

but what else? anythin needed ? or other things just for performance etc?

any help would be appreciated ( i have been researching this on google for ages and carnt find any relevant answers!)
 
For 450hp you would be looking at supertech valves and springs... single groove ones...

Guides (normally exhaust guides as they wear) and stem seals are a given...

Can't have been googling that hard as all the info is on here :)

<tuffty/>
 
Yeh I was hoping to be sending it over to you andy once iv bought the parts! :). An tuffty I have been searchin just hard to pin point what I was after. Iv already got ferrera exhaust valves here. So could I get the supertech intake vavles/springs an thed run fine together I presume?
 
To add, its not really power that dictates valvetrain but where the power is in the rev range.
If its a big turbo with large housing then power is goimg to be later and you will want to rev more for a decent power band.
Thats when the stock stuff is inadequate.
Good vid on youtube of a bench test of stock valvetrain and they reckon they had valve float at 7500 (bench test tho so not quite real world conditions) so thats when you'd benefit from Ti springs and retainers, and inconel exh valves to better deal with heat, and single groove for security.
The video is also accompanied by an uprated test, all supertech i think, that was taken to 9k without float, although it was a little unfair as they use solid lifters, which 99% of people wont run, or need to run.

Build the head around the other hardware, predict what you need to rev to.
Unless youre made of money just do the whole lot and rest assured its bombproof :thumbsup:
 
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limbo118118 said:
Yeh I was hoping to be sending it over to you andy once iv bought the parts! :). An tuffty I have been searchin just hard to pin point what I was after. Iv already got ferrera exhaust valves here. So could I get the supertech intake vavles/springs an thed run fine together I presume?
Click to expand...

Exhaust valves on their own are just a marginal upgrade to the whole valvetrain... as superkarl has mentioned its revs thats the issue... to get 450hp from a 20v normally means biggish turbo and with a biggish turbo comes later spool narrowing the power band... more revs will increase that power band and bigger turbos will still provide flow at those higher revs... a decent setup will make power at as many revs you can throw at it (Bill's Ibiza revs to 8.5k on hydro's with no power drop off)..

Most valve train failures are from worn guides and the valve not seating right at high revs... strains the valve and it breaks... OE exhaust valves are sodioum filled so pretty good to start with but std springs will be an issue...

For the road you want to be aiming at 7.5k to 8k tops... my rev limit is set at 7.8k currently...

As karl mentioned above you need to build around the spec you are going for and the spec can be determined by what you want from the hardware... have seen too many cases of throwing parts at a car and non of them working properly together as the spec is just wrong... start with intended use and power goals... its easier to spec from that and determine what other hardware you need to support it...

<tuffty/>
 
superkarl said:
To add, its not really power that dictates valvetrain but where the power is in the rev range.
If its a big turbo with large housing then power is goimg to be later and you will want to rev more for a decent power band.
Thats when the stock stuff is inadequate.
Good vid on youtube of a bench test of stock valvetrain and they reckon they had valve float at 7500 (bench test tho so not quite real world conditions) so thats when you'd benefit from Ti springs and retainers, and inconel exh valves to better deal with heat, and single groove for security.
The video is also accompanied by an uprated test, all supertech i think, that was taken to 9k without float, although it was a little unfair as they use solid lifters, which 99% of people wont run, or need to run.

Build the head around the other hardware, predict what you need to rev to.
Unless youre made of money just do the whole lot and rest assured its bombproof :thumbsup:
Click to expand...


got a link to the uprated valvetrain video karlos?
 
Thanks alot for your help fellas feel ive learnt alot just reading these few posts! So with me already having the sss ferrera exht vavles. Its worth my investment to get the supertech spring/titanium retainer set aswel as supertech intake vavles. Then possibly a port and polish from andy an il be safe! :) any idea what I could safely rev to with this setup? Cheers
 
Supertech retainers are designed for the supertech single collet valves... better off selling the ferrera valves and buying a complete set of supertech valves/springs tbh..

With that you can rev to around 8k (8.5k at a push with thicker oil) on hydro followers and 9k with solid... for fast road/occasional track then stick to hydros

<tuffty/>
 
Hmm il have to have a think then with my choices! Is there any where in the uk that sell supertech setups? Just getting them from the states I hate all the hidden charges :s
 
superkarl said:
Id speak to some of the big US retailers about what springs + retainers to use with the ferrea stuff IF its a hassle to get rid and change etc.
Click to expand...

Ferrera do their own but not cheap... you could also use Cat Cam springs... just need to make sure they are compatible with std three groove valves...

<tuffty/>
 
Think il work out better to sell the ferrera which shouldnt be hard as there brand new in packaging an then speak to bill about ordering the supertech setup :)
 
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