Larger Valves in a 4efte head

EP91_Chris

EP91_Chris

Member +
I've heard 4age valve springs do fit, but I can't remember if it's the 1st gen or 2 gen. Valves will fit, but need a bit of machine work.

Edit: RHD Japan have cruise valve springs for £155 at the moment which isn't too bad.
 
Phil

Phil

Super Moderator
EP91_Chris said:
I've heard 4age valve springs do fit, but I can't remember if it's the 1st gen or 2 gen. Valves will fit, but need a bit of machine work.

Edit: RHD Japan have cruise valve springs for £155 at the moment which isn't too bad.
Click to expand...

from reading its def not the 20v ones, nor the double spring sets.

if someone had the 4efte vs 4age 16v specs that would be great.

the machine work : well ive talked to a couple of engineers and machining the groove for the collet is apparently tricky business and must be done to a crazy degree of accuracy.

so really up in the air at the moment.

Phil
 
S

Skalabala

Member +
Not worth it to get bigger valves bud. Just open up the throat and 3 angle job on the valves.
Better springs is worth something.
 
Phil

Phil

Super Moderator
Skalabala said:
Not worth it to get bigger valves bud. Just open up the throat and 3 angle job on the valves.
Better springs is worth something.
Click to expand...

anyone know if 4age springs are stiffer than 4efte?

any know where to find specs of such things?

Phil
 
R

Rev

Member +
Looking at these links for the 4age the valves dont seem to have overly high pressure requirements.
Given that the stock Starlet springs can work with Jam type ecu at 8000 rpm.


LINK 1 http://www.billzilla.org/4agstock.htm
LINK 2 http://www.billzilla.org/engvalve.htm

16v 4AGE heads specifications -
- Valve included angle (angle between the inlet and exhaust valves) - 45°
- Minimum valve spring seat pressure to allow for 7,700rpm - 35lbs, or 16kgs
- Inlet valve diameter - 29.5mm
- Exhaust valve diameter - 25.5mm
- Both valves have 6mm diameter stems.
- Cam bucket diameter 28mm, shim diameter 25mm

Reading this link it seems the 20v head has smaller inlet valves ( less mass ) so each spring needs even less pressure than the 16v above
the second link quotes the smaller valves as 30 lb for 8000rpm+
20v 4AGE head specifications -
- Valve included angle (angle between the inlet and exhaust valves) - 35° (I think ...)
- Inlet valve diameter - 26.5mm
- Exhaust valve diameter - 26mm
- Both valves have 5mm diameter stems
- Cam bucket diameter 23mm, with very small shims between the valve stem top & bucket
 
Last edited:
Phil

Phil

Super Moderator
Rev said:
Looking at these links for the 4age the valves dont seem to have overly high pressure requirements.
Given that the stock Starlet springs can work with Jam type ecu at 8000 rpm.


LINK 1 http://www.billzilla.org/4agstock.htm
LINK 2 http://www.billzilla.org/engvalve.htm

16v 4AGE heads specifications -
- Valve included angle (angle between the inlet and exhaust valves) - 45°
- Minimum valve spring seat pressure to allow for 7,700rpm - 35lbs, or 16kgs
- Inlet valve diameter - 29.5mm
- Exhaust valve diameter - 25.5mm
- Both valves have 6mm diameter stems.
- Cam bucket diameter 28mm, shim diameter 25mm

Reading this link it seems the 20v head has smaller inlet valves ( less mass ) so each spring needs even less pressure than the 16v above
the second link quotes the smaller valves as 30 lb for 8000rpm+
20v 4AGE head specifications -
- Valve included angle (angle between the inlet and exhaust valves) - 35° (I think ...)
- Inlet valve diameter - 26.5mm
- Exhaust valve diameter - 26mm
- Both valves have 5mm diameter stems
- Cam bucket diameter 23mm, with very small shims between the valve stem top & bucket
Click to expand...

thanks man.

found this on zetec valves as i was encouraged to look by turbogrant.

http://www.ebay.co.uk/itm/FORD-ESCO...arts_Vehicles_CarParts_SM&hash=item589dc0ef28

these seem to match, except ive not seen anything on length..

96.7 is the Zetec (but 28mm dia)
99.75 is Supra 7mgte (but 27.5mm dia)
??.?? is 4efte (but25mm dia)
??.?? is 4age (but 25.5mm dia)

Help with stock valve length please :)

Phil
 
S

Skalabala

Member +
Fitting bigger exhaust valves will result in worse shrouding :( The valve is against a wall and with a bigger valve the gap gets smaller.
 
R

Rev

Member +
1.075'' 3.740'' .236'' 45 SG V5306
27.305 dia length 94.996 5.994 shaft

1.082 3.860 .2350 45 SG V533
27.483 dia 98.044 length 5.969 shaft


Lighter Shaft higher revs for larger dia valve?
1.075'' 3.757'' .216'' 45 SG V5
27.305 dia 95.427 length 5.486 shaft
 
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Phil

Phil

Super Moderator
Rev said:
1.075'' 3.740'' .236'' 45 SG V5306
27.305 dia length 94.996 5.994 shaft

1.082 3.860 .2350 45 SG V533
27.483 dia 98.044 length 5.969 shaft
Click to expand...

1.071/3.787/.2350
27.2/96.2/5.97

1.082/3.860/.2350
27.5/98.0/5.97

I must have been rounding things abit wrong there in the inch to mm conversion calculator but yeah same ones i found. lol

first is the best, and its from a toyota so good chance the collet ring will be the same.

just investigating now to see if there is enough metal beyond the collet ring if i was to cut the access off the top of the valve. (2.9mm

Phil
 
Phil

Phil

Super Moderator
Skalabala said:
Fitting bigger exhaust valves will result in worse shrouding :( The valve is against a wall and with a bigger valve the gap gets smaller.
Click to expand...

genuinely interested in the shrouding issue and any way to avoid it.

is there room when compared to the bore to removed some material from the cyclinder head and not start a fight with the headgasket?

Phil
 
S

Skalabala

Member +
Phil said:
genuinely interested in the shrouding issue and any way to avoid it.

is there room when compared to the bore to removed some material from the cyclinder head and not start a fight with the headgasket?

Phil
Click to expand...

Having trouble to find pictures for you bud :(
1/3 of the valve is against a wall.
DSCF0078.jpg

You remove the wall as far as you can.
Something like this.
head-porting2_clip_image008.jpg


You might find this absurd but a smaller exhaust valve in this case might even be a better option.
 
Phil

Phil

Super Moderator
thanks for pic, was there two? i can only see the first one.

These just arrived..... better start looking for a spare head to practice on!!







Phil
 
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