SIP racing sells the shim in smaller sizes than toyota. Be sure to allow for a long time for making them and shipping. When i shimmed my head it took me about 2 weeks to recieve some shimes to check the clearances.I had to get smaller shims because the vavale were ground. Then about 2 more weeks to recieve the shims to finish the job. Best sounding head I have ever had in my car. This is motor number 6