6G Celicas Forums

Has anybody done this or know the effects it will have on a 5f?

never done it but from what i have heard it it reduces weight and allows for better performance... but this was done mostly on iron blocks. don't know if a weakend head could handle the stress..

It wasn't ever done to save weight. When you're taking about shaving a head, you're talkin about taking 0.040". Thats not even going to save a pound. Its done soely to raise compression.

Its totally doable on our motors and will improve performance. It needs to be done by a good machine shop. Since you'll have the head off anyway, its a really good idea to have a valve job done and put in new seals at the same time. You won't want to take too much off or you'll have to have custom pistons to provide enough clearance for the valves. You're also not going to want to raise the compression much past 10.5:1 if you're going to continue running pump gas. Some combustion chamber designs will allow for higher compression than that on pump gas, but ours likely will not.

Try to find a machine shop that does performance work on imports and preferrably one thats worked with toyotas before. The quality of the shop will make or break the deal.

I've done this work in addiction to valve job and P&P and the result is amazing!!!

Yes, results typically are fairly good... but you'll sacrafice low-end torque for the high-end power... typically a shave job can slightly reduce displacement...

Thanks for all the info. It sounds like a good idea so I'll do it this month and let you guys know how it went. How much should i shave off of it?

you should call toyota. There is a max amount that you can shave off the head before you will loss the seal. Also you should contact Ferra about making you some oversized ss valves and springs. The valves should be made 1 mm over stock and will better the air flow of the 5sfe head.

For porting your head I would have it gasket matched.

Once you have done all this the only thing left to do to the head is get a set of regrinded cams and you will be set.

-Bryan-

I'm sure you could use old school 4age springs. I believe HKS offers a set at a good price.

Jon

you can us evalve springs of 4AGE?? are you sure?? which 4AGE?? Thanks

haha, yea, after re-thinking that comment, I am sure I am wrong. BUT, HKS does make valve springs for a 4age. If you are going to custom the head....


I really don't know if they would work or not. I have no clue about the actual measurements of the heads, or what it would take to fit them.

Random thoughts are what you get when you contemplate swapping heads.

You can find them at Nopi.com though if you are curious. Look under old school MR-2 (89 works)

Jon

Shaving the head does not change displacement at all. Displacement = bore x stroke. Unless you're boring the engine or changing the crank, the displacement stays the same. Changing the deck height (shaving the block) or shaing the head will raise compression and decrease p-v (piston to valve) clearances. Like I said before, just make sure you have the work done by a shop that knows what they're doing.