New cams old shims - good idea or no?

[roadsailing]

hi all, simple question.

engine is a 4AGE but tha tshouldnt matter too much.

when i get cams for my "next" engine i'm assuming i will need to re-shim all the buckets.

is it an issue to use old shims with new cams? (i'm picturing an old shim will be concave, wheras a new cam lobe will be flat, resulting in wear on the corners on the cam shaft)

i have access to a few wngines worth of shims and wouldnt mind re-using some, should i just not be a tightass and buy new shims? go shimless buckets?

[amichie]

hi all, simple question.

engine is a 4AGE but tha tshouldnt matter too much.

when i get cams for my "next" engine i'm assuming i will need to re-shim all the buckets.

is it an issue to use old shims with new cams? (i'm picturing an old shim will be concave, wheras a new cam lobe will be flat, resulting in wear on the corners on the cam shaft)

i have access to a few wngines worth of shims and wouldnt mind re-using some, should i just not be a tightass and buy new shims? go shimless buckets?

Just reuse them. Some aftermarket cams are too big for the standard shim over bucket design but if your new cams are ok you can reuse shims without any worries.

[stahlz_ae86]

What size cams are you going to? If you are to upgrade the cams substantially shimless buckets would most likely be your best bet.

[Crazyracer]

In a perfect world you would probably get new shims to go with the cams but you should be OK using the old ones. Just check them all to make sure there's no damage to the surface.

In any case you'll probably need to adjust the shim thicknesses to set up the clearance on the new cams, so you may need to get new shims or get you're existing ones re-ground and re-hardened.

And as Amichie says, some cams are too big to use with the standard "shim over" style buckets. If you go for big cams you'll have to track down a shim under kit. TRD use to do one, but there may be some other options available now or suss something from a different model.

[roadsailing]

yeah i only want 272 or 288 at the biggest, 8.5 mm lift, which are advertised to be fine with shim on bucket. (HKS ones, not TRD 10mm lift)

3SGTE stuff is compatible apparently, shimless would cost about 300 to set up correctly,

i haven;t even priced up shims yet, but i figured it will be a good way to keep costs down.

[RobertoX]

Didn't takai write an article on toymods about using shimless buckets from an echo? $300 sounds around about the mark...

[roadsailing]

yeah he did, was a good writeup.

[30psi 4agte]

I have a shimless bucket conversion they do cost abit and you have to wait forvever as the shims are ex japan...... So you would wanna measure the clearence correct because if you dont ...... it s not so easy to just buy more buckets.

Anhow using the old shims will be fine ! i think you will find that the cam is more likely to wear before the shim does

[styler]

i dont know if im missing something here but dont all reground or aftermarket cams need new shims?

say if you get a mild regrind and the base circle is undersize, that definately needs new shims for extra height as well as each lobe/bucket clearance.

then a hardfaced and reground cam with the same base circle still needs individual shims to get each clearance right for each lobe/bucket.

and aftermarket with the same base circle would also
need individual shims to suit each lobe/bucket clearance.

too much clearance or not enough clearance cant be a good thing
with something like valve trains which are set up so precisely.

i mean shims are very precise! 0.02mm or 0.05mm graduations so its quite exact shim sizes. you can get them made up to suit most common diameters easily and custom specs too. try precisionshims.com.au in melbourne for auswide delivery. its about $9 a common size shim so 8 valve = $72, 16v = $144.

you may luck in and have the sizes you need from all the engines you have but its a small chance and you need a micrometer to measure them properly.

im going for new shims as its probably cheaper than machining down the old ones and definately cheaper than building them up and machining them i would imagine.

thats my thoughts anyway...

[Crazyracer]

I think the Gen 1, 3SG buckets are the correct size for 4AGE 16V, but the standard ones are still shim over. So you still end up needing to get an after market kit for it.

The Gen 3, 3SG has shim under, but I'm pretty sure they are larger diameter, so you would need to get the head machined to accommodate them.

[styler]

i see a lot of people change the factory 4ag shim over bucket to shim under bucket conversion as well as shimless designs, but each setup has its different costs in the end. its a lot more reliable to have shim under bucket or shimless if possible at higher rpm especially if you have mild or hotter cams. saw this page with a 4agze shimless conversion might be of some help if its the same setup as 4ag valvetrain?

http://www.e-wire.net.au/~nrparker/M...new_engine.htm
its at the bottom under "more power?"

http://www.billzilla.org/4agmods.htm
some 4ag tech ,halfway down under 200 -220 hp. thanks billzilla