How to put 2JZ cams in a 1JZ engine.
There is a lot of information about putting upgraded cams in a 1JZ-GTE engine. One of the cheaper swaps is using 2JZ cams and machining them for use in a 1JZ engine. However, a lot of information and photos have gone lost throughout the years. We’ve done extensive research about all information that is available on the web and we hope to have provided a definitive, complete and persistent source of information with this page. Please feel free to share your added information about this topic with us.
Note! No information was retrieved by ourselves. It was all posted by others on other online media. We’re just trying to get all the scattered information in one place.
2JZ cams have some higher lift and better duration. According a post on soarercentral where someone actually dynoed and compared the results there is about 20whp to win thoughout the band using JDM (Aristo) 2JZ cams and 10whp extra (so about 30 whp0 across the band with the USDM 2JZ camshafts.
Cam specs of the 2JZ engine:
|Description||JDM Spec||USDM Spec|
|Intake lift (mm)||7.80||8.25|
|Intake duration (deg)||224.00||233|
|Intake Open BTDC (deg)||7.00||7|
|Intake Close ABDC (deg)||41.00||50|
|Intake Centre ATDC (deg)||109.00||113|
|Exhaust lift (mm)||8.40||8.4|
|Exhaust duration (deg)||236.00||236|
|Exhaust Open BBDC (deg)||52.00||52|
|Exhaust Close ATDC (deg)||4.00||4|
|Exhaust Centre (deg)||114.00||114|
To get the 2JZ camshafts to work in a JZ they need to be machined first as the 2JZ’s front side won’t fit the bearing. They are just a bit beefier and they need to be machined down to meet the 1jZ specs. This goes especially for the exhaust side. See picture:
We don’t have the exact measurements for what needs to be machined off but we found the drawing below for reference.
Please be careful and measure up everything before starting,
Also keep in mind that the front of the camshaft has a larger diameter on the 2JZ camshaft so you will need a different camshaft seal.
Everywhere we look we see the same part number (TC-12549). As soon as we have the SKF equivalent we’ll mention it here also. See picture below for reference:
|Used seal measurements||2JZ OEM seal measurements||1JZ OEM seal measurements|
|Seal used: TC-12549 (Used on some jaguar transmissions)
Inner diameter: 40mm
Outer diameter: 50mm
|2J SEAL Inner diameter is around 40mm
2J SEAL Outer diameter is around 52.5mm.
|1j SEAL Inner diameter is around 38MM
1j SEAL Outer diameter is around 50mm
When installing the camshafts please make sure you get the oil feed/drain holes line up correctly on the intake camshaft because they tend to be offset. Depending on how the machine work was done it may or may be a problem getting the oil feed holes to line up. There are reports of people having no trouble at all, but there are also a number of people that report issues on the rear end of the camshaft. You can use some nail polish on the camshaft to check whether or not you have a problem.
There are several solutions for this. The most obvious would be to drill out the oil passage in the head as pictured below. Another option would be to enlarge the hole in the camshaft somewhat.
We found this pictorial done by Cihan Aday:
Nail polish or paint on the cams:
You can clearly see what will and will not line up:
The front lines up just fine:
And last but not lease a dyno of the stock 1JZ cams versus the USDM 2JZ cams