EOI: Aftermarket cam grinds and Valve spring group buy

[Adam.Findlay]

today i went back to talk to peter kennard of kennelly cams, he said he can supply us uprated valve springs which wont bind under the 10.5mm lift of the new cam grind @ $345 for a set of 24 springs and he can do the regrind for $630 (all in New Zealand dollars)
this cam grind will not require any other parts, the stock hydraulic lifters(lash adjusters) will compensate for the grind on the cam, the stock retainers are the right size to fit evo valve springs, the only thing you have to change is the valve spring as the stock valve spring will bind @ 10.5mm lift or even before then.

If anyone is intrested in this cam grind please get back to me before the new year as I plan to send my set of cams in to get reground in early january.

[Kenneth]

Have you had any indication of what this will do to the torque curve? I am not so keen to move the peak torque point much to the right but otherwise am quite interested in this thread.

I am going to be going more for boost than RPM.

[Adam.Findlay]

no not yet I assume it will shift the powerband up. but i dont know specifics yet its going to have to be a trial thing, I will be the tester if needed, but i can imagine it wont work so well with the tiny stock turbos (although it may help with stoping then running out of puff past 6k rpm). the duration around the same as Zentac's cams he had in his 600+hp 6A13TT so worth looking at his power graphs. the 10.5mm lift offered on this regrind is bigger then the the 8.5mm lift Zentac's cams had though which I bet will help when you are planning on pushing silly boost at any rpm

[foxdie]

I too think we'll have to see the proof of the pudding here Adam, if you can, get a prototype built and dyno'ed before and after so we can visually see what the benefits will be

Ps. Already given you rep, certainly done a lot of homework on this

[Adam.Findlay]

righto, well I will be getting a set of these cams for my engine in the build regardless, but if a few more people express their intrest I will install them into the functioning engine thats is in my legnum, road tune it like i have done before and then pay for a power run on a dyno.
and if the dyno result is a decent one I may get a 2nd set made
certain people may be able to shed some light on the subject, once i had a conversation with fully, he said that his purple galant had reground cams in it and he mentioned that it "woke the car up alot" but he will have to be the man who goes into details about it

[Kenneth]

I should be good for a set Adam. Let me know when and I can send you whatever is needed

[Adam.Findlay]

will do kenneth, will organise closer to the date after the christmas period.

[Adam.Findlay]

Bit more information on head work. Just got two 4G63T valves today one inlet and one exhaust. the measurements are as follows

Evo Inlet Valve
- Diameter = 34mm
-Length = 110mm
-Stem diameter = 6.6mm

Evo Exhaust Valve
-Diameter = 34mm
-Length = 110mm
-Stem diameter = 6.6mm

followed by 6A13TT valve measurements

6A13TT Inlet Valve
- Diameter = 33mm
-Length = 104.8mm
-Stem diameter = 6mm

6A13TT Exhaust Valve
-Diameter = 28.2mm
-Length = 104.8mm
-Stem diameter = 6mm

This Possibly means 6A13TT heads can take evo or aftermarket evo titanium or billet valves with a re work of the valve seat and chainging the valve guides to accept the bigger valve stem of the 4G63T valves.

the inlet evo valve fits easily within the standard 6A13TT valve seat so only a regrind of the valve seat and valve guides would be needed on the inlet side. however on the exhaust side it is hard to tell if the stock valve seat can accomidate the extra 2.3mm diameter exhaust valve I Still have to take the head into a cylinder head specalist to get their opinion on the matter.

If We can use evo valve guides with evo valves. that means we can use aftermarket evo dual valve springs. dual valve springs require their own special retainer and due to our engines having the 4G93T valve stem size, we cannot use 4G63T retainers on our standard valves. Main reason for this being to make the heads safer to rev higher without valve float aswell as making the heads breath better helping with Volumetric Efficency therefore more power

there is also aproxx 5mm difference in length between 4G63T and 6A13TT valves, however this should be taken up by the lash adjuster, especially if used in conjunction with the cam regrind as the cam regrind makes the base circle of the cam lobe smaller to get larger lift from the cam.



Also as an update on the cam regrind information. piston valve interfearance at high lift was getting me worried so today i refitted the crankshaft into my spare block with one conrod and piston attached so I soon can measure the clearance between the lower most point of the valve @TDC and piston @TDC. if there is not enough clearance the regrind may have to scale back the ammount of lift from 10.5mm to a lower value, Will keep you all updated once my results come in.
any construstive feedback is welcomed

[Adam.Findlay]

Cant forget my pictures now....
IMG065.jpg
How Flat a 6A13 piston is hence my worries about valve piston interfearance

IMG068.jpg
Height difference of exhaust valves evo left 6A right

IMG067.jpg
Diameter difference of exhaust valves evo left 6A right

IMG061.jpg
Stem size difference Evo left 6A right

IMG066.jpg
Evo inlet valve left, evo exhaust right

[Davezj]

i know this is an old thread but it is a good place to ask.

this is a question about valve springs.

if i change my valve springs for an stiffer uprated set as in the cam regrind threads, do i have to change the spring retainer and collets that hold the retainers in place.
it just seems a lot of the cost of the uprated valve spring is the billit titainium retainer and not the spring itself.
is it a case of the original retainer is not strong enough for the uprated spring or is it just a supposid weight saving thing.

does anyone know where i can get a set of 24 springs form sets of 16 springs and retainers are avalable all over the place i am searching for the BC1100 spring that adam recommended.

i am not going to buy them now i just need to know where i can get them from.
i can get these from the USA but i will have to pay for shipping and import duty.
http://www.maperformance.com/bc0100-...3-dsm-evo.html
but they come with titianium retainers and there is only 16 of them, i wold have to contact them and see if i can work something out with them to get a set of 24.

[Adam.Findlay]

i know this is an old thread but it is a good place to ask.

this is a question about valve springs.

if i change my valve springs for an stiffer uprated set as in the cam regrind threads, do i have to change the spring retainer and collets that hold the retainers in place.
it just seems a lot of the cost of the uprated valve spring is the billit titainium retainer and not the spring itself.
is it a case of the original retainer is not strong enough for the uprated spring or is it just a supposid weight saving thing.

does anyone know where i can get a set of 24 springs form sets of 16 springs and retainers are avalable all over the place i am searching for the BC0100 spring that adam recommended.

i am not going to buy them now i just need to know where i can get them from.
i can get these from the USA but i will have to pay for shipping and import duty.
http://www.maperformance.com/bc0100-...3-dsm-evo.html
but they come with titianium retainers and there is only 16 of them, i wold have to contact them and see if i can work something out with them to get a set of 24.

No you do not need to change your retainer and collets when upgrading to a stiffer single spring.
you do need to change the retainers when installing dual valve springs however as the retainer is machined so the tops of both inner and outer springs seat nicely.

The use of titanium retainers is purely a weight saving thing, as valve gear mass is the cause of valve float at high rpms, but if you install a good set of single springs (such as the brian crower ones) you will snap a conrod or rod bolt before you get valve float due to the small size of our stock rods.

Also the evo retainers do not fit due to the 4g63T having a thicker valve stem

hope this helps

[Davezj]

thanks Adam, i could not have asked for a more informative response.

have some rep.

[Adam.Findlay]

thanks Adam, i could not have asked for a more informative response.

have some rep.

[Davezj]

Hi adam @Adam.Findlay
i have asked this question in the group buy thread which is the wrong place so i asking it here as well. i will go back and delete for there.

this is the evo spring you recomened
BC1100 Seat: 1.550" @ 84 lbs / Open: 1.000" @ 235 lbs / Coil Bind: 0.935" (no machine work required)
will these valve springs work for our engine
BC1140 Seat: 1.460" @ 84 lbs / Open: 1.000" @ 235 lbs / Coil Bind: 0.935" (no machine work required)
they are for a 6A72 3000 GTO vr4 engine and come as a 24 sping set.
but this size is different 1.460" instead of 1.550" not sure if this is the uncompressed length of the spring or something like that.
you can tell i know nothing about valve springs.

[wintertidenz]

If I remember correctly the seat measurement is the diameter of the spring itself at the bottom. You may find that the GTO ones won't fit.

They're probably the same price as the Evo ones anyway, and they are known to fit. Adam would have done a fair bit of research before recommending the ones he did

[Adam.Findlay]

Hi adam @Adam.Findlay
i have asked this question in the group buy thread which is the wrong place so i asking it here as well. i will go back and delete for there.

this is the evo spring you recomened
BC1100 Seat: 1.550" @ 84 lbs / Open: 1.000" @ 235 lbs / Coil Bind: 0.935" (no machine work required)
will these valve springs work for our engine
BC1140 Seat: 1.460" @ 84 lbs / Open: 1.000" @ 235 lbs / Coil Bind: 0.935" (no machine work required)
they are for a 6A72 3000 GTO vr4 engine and come as a 24 sping set.
but this size is different 1.460" instead of 1.550" not sure if this is the uncompressed length of the spring or something like that.
you can tell i know nothing about valve springs.

BC1100 have an installed height of 1.550" where the BC1140's are 1.460" (as per the data you have given me)
this means that the BC1140's when installed in a 6A13TT would have nowhere near enough seat spring pressure. and would also have far less spring pressure across the nose.

Also there are no dimensions given to internal and external diameter of the coil spring so I cant tell if they would fit in the standard retainer/spring seat.

with how cheap the 4g63 springs are just buy 2 sets and sell the spare 8 here on the forums to the next person who wants to do springs.

And remember. you just want the springs. as the 4g63 retainers will not fit the 6A13TT valves.

[Davezj]

Cheers adam,
i now have a lot more info to play with.
i want to build a pair of heads ready to drop some reground cams in without having to change the valve spring with the heads on the engine. i have a full set of seals to build on to the heads as well, i just don't have the money to do it all at the same time. So i thought i would do it in a considered way to make it easy for me in the future.

it is a good point about buying 2 sets, i can get 16 springs for £50 but the postage and duty and VAT on top of that makes them about £100 a set of 16.

[swinks]

In my research BC1100 spring may be bit over-do. They do work nice, but are extremally hard for just 262 re-gring cams (unless you going to move up rev limit).
IMHO, springs from Evo 8 MR or FQ (due to similar camshaft profile) will be half way between stock vr4 springs and extra hard BC1100 ones. I think they are good if you won't do anything extreme in tune after cams fitted. But, BC springs are easier to source.

[Davezj]

In my research BC1100 spring may be bit over-do. They do work nice, but are extremally hard for just 262 re-gring cams (unless you going to move up rev limit).
IMHO, springs from Evo 8 MR or FQ (due to similar camshaft profile) will be half way between stock vr4 springs and extra hard BC1100 ones. I think they are good if you won't do anything extreme in tune after cams fitted. But, BC springs are easier to source.

So are you say the stock evo valve springs are harder than the stock VR4 ones but not as hard as the BC1100.
so if i got some used evo valve spring from soeone on MLR they would be a midway option.

are you changing your valve springs tomasz.

[Adam.Findlay]

Dont bother with stock Evo springs, waste of time.
our rockers are roller follower so running heavy springs is not an issue. it will not increase cam wear like it does on old flat tappet V8's

heavier springs will help seal the valve against its seat properly, there is probably a horsepower or two in just having proper springs. and for the cost of springs like the brian crower's its not worth not having them.

if you want to get a set of cams off me later on I can supply springs and you can install them before the heads go onto the motor, saves you the headache of sourcing locally.
only issue with that is import tax.