TOMEI 264 PON CAMS for 4AGE; Valve Springs

[GeeEss]

I am having a Bigport 4AGE freshed up + ported to suit Silvertop Quads. Cams are 264Deg Tomei Pon Cams.

Engine shop called me this morning saying that I need to supply them with Tomei Valve springs to suit as my OEM Valve springs are only good for 7.5mm Lift. I queried this saying that according to my research OEM springs should be OK to about 8.5mm and that these Cams should be Plug+Play on standard Valvetrain. I am 99% sure only the Pro Cams need uprated Valvesprings.

The supplier of the Cams said to request the spring pressure readings from the Workshop; when I called back the guy said the problem wasn't the rates, it was the potential recoil / binding and that the OEM springs were only good for about 7.5MM Lift.

Can anyone help out here?

Cheers; George

[DreadAngel]

Misread it for Silvertop head

Need to change my aspect ratio for my vision changed...

[oldcorollas]

bigport, not silvertop.....

[DreadAngel]

Gah... My bad thought it said Silvertop head =|

[oldcorollas]

regardless, i thought 8.1mm cams were ok, but 8.35 were touch n go? (ie HKS jobies)
or was that for shims....

[trdee]

have never heard of this before Gee Ess. Plenty people running cams around the 8mm lift area with stock valvesprings with no issues....

[GeeEss]

Thanks guys; chewing my fingernails about this one. They said the clearances are borderline & that because it's going to used on the Track I should use uprated springs to be on the safe side.

It's not the money that's the issue but the time; another 2 weeks waiting for TRD / Toda stuff out of Japan is just extending this saga.

IF I decide to go with this does anyone have any suggestions re Springs < Tomei don't make Valve Springs for the 4AGE >.

So far I've found 3 sources;

1. Toda < Part # 14750-4AG-000 > $185 delivered / 2 weeks
2. TRD < Part # 90501-AE901 / Group A spec > TRD say to use them in a set but* < assoc. Buckets & Retainers are NLA anyway> $250 Delivered / 2 weeks
3. Performance Springs < Part # PS3506/905-16 > http://www.performancesprings.com.au (in stock) / $245 Delivered / In Stock

*Unless someone has a compelling reason otherwise, I will be using these Springs with the standard Lifters/Buckets and retainers.

[oldcorollas]

how high will you be revving and how long?

compelling reason? spitting shims at high rpm perhaps?
you can get other shimless or shim-under buckets from other toyotas.. 1NZ comes to mind(?) something like $30 each

[GeeEss]

Isn't that overkill (+ another 16x 30= $500!) I thought those were only needed if you had a Blueprinted / balanced donk and were pulling 9-10K RPM regularly (i.e. drfiting).

Don't forget, my bottom end is basically stock and I can't see me going past 8500 RPM on a good day. . .

[trdee]

spitting shims is more about cam profile and cam lift than it is about revs. the thing to worry about on your valvetrain with high revs is valve float (boost also affects this).

supertech also do valvesprings fyi

[oldcorollas]

"blueprint" doesn7t really have any meaning for a toyota engine...
the term just means "bringing an engine up to the specs it was SUPPOSED to be built to ie holden and ford

Trdee, what happens when your valves float, when you have shim on top?
boost doesn7t affect it as much as you think... abotu the only time there is less pressure under the intake valve than above, is when the valve is open anyway...

[GeeEss]

OK; I've taken this on board and u/s the points made but overall feel none the wiser; one of their (LW Parry's) guys (Adam) races a 20V 4AGE engined Clubman but he's been sick all week. I think I''ll wait & ask his advice before deciding.

RE: Supertech; I know but @ $295/set they're $110 more than the quote I got from Toda Australia for a set delivered to my door.

Anyway, appreciate the comments. . .

[GeeEss]

Further to my last Post; can anyone confirm the Free Length, Installed Hieght, Seat Pressue & Lift-to-bind of the TRD Valve springs?
Seems to me that they are stiffer than OEM but only have same lift (7.5mm). . .

[oldcorollas]

from TRD website for 16V http://www.trdparts.jp/english/parts_engine-4a-g16.html
Part No./ Free Length/ Fitting Length(mm)/ Fitting Load(kg)
90501-AE851 (group A spec) /40 /34.7/ 20
90501-AE901 (N2 spec) /41.03/ 36.1/ 18

the 16V cams are either 7.5mm lift, or 10-11mm lift. 851 is used with inner shim set

for 20V http://www.trdparts.jp/english/parts_engine-4a-g20.html
10309-AE001 /42.3 /38 /15

no bind height

Olskewltoy (from here) said

I currently have a set of TRD single springs 90501-AE851.
They have a seat pressure of about 50#s, a pressure of 130#s at .350 lift) Coil bind occurs are .425 lift(10.7+mm)
TRD single springs.....90501-AE851 (about $165 per set) use with OEM retainer... OEM spring seat... OEM valve seals.
Lift capability to .425"(10.795mm)

spring pressure...
@ the seat = 50#,
@ .310 lift 116#,
@ .350 lift 124#,
@ .375 lift 130#
@ .400 lift 135#
@ .425 lift 141#

re supertech

I have the Supertech dual kit, which is an awesome kit, but the guides have to be undercut for the smaller seals. Stock seals will not fit inside the inners springs. Problem is that nobody makes a cutter to cut the guides in the head.
I think I have it figured out though. I am having a special cutter made as we speak.

edit: oldskewl said he believed (but did not know for sure) that the 901 can7t be used with standard retainers etc...

[oldcorollas]

from here http://www.aeu86.org/viewtopic/ae86/p/129648

TRD 90501-AE851 springs will work with the stock retainers and the lift or you can get a kit from Supertech incl. Titanium retainers