Oversive Valves to TUJ4 Engine

[nazmitocak]

Hi All,
I am planning to fit over size valves to my J4 engine,

http://atspeedracing.co.uk/products/index.php?main_page=popup_image&pID=172&zenid=51ecbcd03e1be8a66b370c561a188680

here are the dimensions of the valves, İs there anybody fit these to j4 head before, I need help

[atspeedracing]

hi

the inlet valves MUST have larger valve seats fitted. this is a specialist job

exhaust valves work on the original valve seats.

cylinder head porting strongly advised, especailly to match to inlet seats.

- colin

[welshpug]

Do you need bigger valves? many high power TU's use standard diameter valves (not standard valve, just standard diameter...)

[nazmitocak]

hi

the inlet valves MUST have larger valve seats fitted. this is a specialist job

exhaust valves work on the original valve seats.

cylinder head porting strongly advised, especailly to match to inlet seats.

- colin

Did you fit these valve to TUJ4 Head with 32 mm seats before ?
My man who will machine the head told me that, there are rings in side the seats, if we bore the valve seats to 32 mm, the rings will be damage so it will not work on J4 head- he said ...
Is he right, or not specialist enough.
I could try to find someone morre experienced on his job

[Ross]

Alternatively use a JP4 head?

[atspeedracing]

hi

the valves do go straight onto JP4 seats, but not on the J4.

but to use the J4 head, you must use larger inlet seats. this is what we have done on my J4 head.

this was carried out by nick @ Automotive Machine Services http://www.automotivemachineservices.co.uk/contact.htm

there ends up being around 1mm of material between the seats, but done properly, they do not fall out.

- colin

[atspeedracing]

my head - for reference -TU5J4 fitted with sinus stainless valves

http://i639.photobucket.com/albums/uu114/106-gti-colin/106 oct 2010 - santa pod build diary/DSC00554.jpg

http://i639.photobucket.com/albums/uu114/106-gti-colin/106%20oct%202010%20-%20santa%20pod%20build%20diary/DSC00549.jpg

http://i639.photobucket.com/albums/uu114/106-gti-colin/106%20oct%202010%20-%20santa%20pod%20build%20diary/DSC00551.jpg

regards

colin

[Sandy309]

REC do 29.5mm inlet valves for the J4, that will go on the standard inserts no problem. You can achieve over 200bhp N/A on that size if the headwork is good and all other components are well matched/chosen. Oversizing the inserts is a very specialised job as has been said and not cheap, consider what it will achieve for the cost if the rest of the engine spec is likely to be middle of the road? I wouldn't insert the head for bigger valves unless you have regs to conform to that restrict you to the J4; if you are determined that you need bigger than 30mm valves, then JP4 makes more sense as the inserts will be no trouble at all.

[nazmitocak]

CITROEN SAXO (1996 - 2012) INTAKE, 1MM OVERSIZE 6000 SERIES COMPETITION VALVES
1.6L - 16 Valve (TU5J4)
Intake
Head Diameter: 29.8 mm
Stem Diameter: 5.98 mm
Overall Length: 104.4 mm
Tip Length: 4.9 mm
Reference: 20� Super Flo. + 1 mm over size.


Anybody use ferrea valves, they have +1 mm over size
http://www.ferrea.com/Citroen-Engine-Valves/p34277