Project Toyota Supra MKIV, Part 3: The Cylinder Head

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With the actual head taken care of, it was time to fill it up with quality parts.  In all honesty, I'm reusing my Ferrea components—like the titanium retainers, valves, valve locks and keepers—from the last build, simply because the various pieces have fewer than 10k miles on them and are all still in perfect shape, according to Brad Noland of Noland Cylinder Heads.  We did, however, swap in new dual valve springs per his request.

I was going to retain my HKS 272 exhaust and intake cam combo, but it turns out my exhaust cam had a lobe that was pitting, so we replaced them both with new 272 degree cams from Titan Motorsport.

We think a possible culprit of the pitting is the angle of the factory shimmed 2JZ lifters, which are two-piece and leave a sharp edge on the side, possibly coming into contact with the cam.  Or it could have happened from imperfect measurements from the last engine builder as well. 

To remedy this, we contacted Champion Toyota of Houston for their OE MR2 Spyder lifters, which are solid, fit the Supra, and give us a whopping 35% weight savings.

Our previously used HKS exhaust cam had a lobe that was pitting.  While we technically could have fixed and reinstalled this set, we preferred to start with a fresh pair of bump sticks.

Having read great reviews on the Titan Motorsport camshafts, this was an easy decision for the project.  I chose 272-degree for both the intake and exhaust.  Even with the Precision 71-GTS non-ball bearing turbo I ran last year, the spool-up was fine for me on the street, and I do enjoy that top end.  Plus, they're much less expensive than HKS units.

Titan's 272 cams come with either 9.45- or 9.6-mm lift specifications, the latter needing heavy-duty valve springs like the Ferreas.  However, I chose the 9.45-mm to keep things a little more simplified.  It's still a significant increase over my previous HKS cams, which had 9.3-mm lift.

An exciting find was the fact that the factory Toyota MR2 Spyder lifters fit the Supra.  Once Brad Noland at Noland Cylinder heads took all the proper measurements, we ordered these through Champion Toyota of Houston, my go-to place for all OE Toyota stuff.

Here's why I was excited.  Not only did the MR2 units (left) not have the separate shims like the 2JZ ones (right and rear), they weigh in at only 28.5-29.0 grams, depending on the measurement, versus 44.0-44.5 grams for the factory 2JZ units.  That's a helpful 35% reduction in weight, for a total 372 grams—a lot of valvetrain weight reduced!  Couple this with the 20% reciprocating mass we lost in Part 1 in the bottom end, and this engine should rev up very healthfully.  Also, having a one-piece lifter eliminates the possiblity of the two pieces coming apart in an overrev situation, where the cam and lifter can lose contact with each other.