Project Thread Supercharged 1UZ Bangkok Drag Truck

The 1UZFE EGR Delete Kit is available for sale here.
Bangkok, Thailand
I thought some members would like to see my supercharged 1UZ drag truck project as it unfolds in Bangkok. Feel free to offer comments, corrections, and good ideas. I would appreciate it.

I have a web page devoted to my race projects, including the supercharged 1UZ into my 1990 Mazda Familia mini pick-up drag racer. Go here for project reports and updates:

Please leave some comments on that site too.

Dr. Jeff Harper
Harper Racing Bangkok
Some more information on my supercharged 1UZ project. My race car currently has a 1.5JZ in it with a race-modified A340-series automatic transmission and high stall (4200) torque converter from MV Automatics in Australia. I have really enjoyed this engine/trans combination in my drag truck for many years, won many races, and have run very quick in a very light car (10.60s at 135mph in a 1800 pound, short wheel base car).

But . . . "turbo" is just another word for "muffler" to me . . . and I was suffering from "Wup-Wup Envy": I missed the sound (hell, SONG) of an open-header V-8 race engine. So I decided to go with a V-8. Being in Bangkok made an American V-8 too expensive. Fortunately, the 1UZ is incredibly cheap here, so I bought one. I also had a very good Vortec V9 supercharger (and pulleys), an good used AEM ECU, and a new set of Kelford cams fall in my lap at good prices, so I am running with it.

I have already had a new deep rear-sump oil pan fabricated and the cams installed. I have obtained the 1UZ auto bell housing and had the 1UZ ring gear machined to accept the 2JZ torque converter and race transmission I already have (see photo).

I am planning on going over to the 1UZ in two phases: Phase one - get it running and race it -- quickly and as cheaply as possible. For this I have added a composite 2mm head gasket (retaining the standard head bolts) for an estimated 9.25 compression ratio with the standard internals (pistons and rods), and adding the "yellow top" 430cc top-feed injectors. I am assusming not much boost down low, and a max boost of 10 pounds at near 7000rpm at the finish line. This should work on the race gas I use here. I only need to "run my number" (11.90) at the drag strip to be competitive. I am not looking for huge horsepower, or "as much horsepower as I can get" (another way of saying, "When will it break?"). I need around 400RWHP to run low 11 second e.t.s in my racer. This is a "race car only".

Phase two will be to build a proper race short block with forged pistons, ARP studs and bolts everywhere, even larger injectors, and big forged rods, or perhaps, aluminum race rods (they cost the same). To this I may add a NOS system where only four NOS nozzles feed the 8 intake manifold runners (see photo . . . NOS nozzle locations in red . . . spraying down in a fan pattern). This motor would be used to run the same brackets, but at a faster finish line speed, and/or qualifying for special events, where I may want to hit a 9.99 e.t. for an "Oh Wow!" crowd reaction. That's the plan.

I'll keep you all posted.

Dr. Jeff harper
Harper Racing Bangkok
More progress. My 1UZ has been cleaned and the heads bolted on utilizing a 2mm head gaskets. I have had the Kelford 207 T-1 camshafts installed and pre-lubricated with Crane Cam Lube. The fabricated deep sump pan turned out great. I trailered my Familia drag truck to the shop (175 kilometers across Thailand) for it's 8-week stay for the V-8 transplant. There are more pics and discussion at my web site:

Dr. Jeff Harper
Harper Racing Bangkok
You may wish to check if the front of the inlet cams have been plugged to stop oil leaking out.

My 207's didn't have the plug and that was where the end of my engine started.
Man.... you have more room than you need. I say easy fit, expecially with A/C and P/S removed. Judging by the pics, are planning a rear sump?\

engine looks amazing with polished covers.
Yes, I have had a deep rear sump oil pan fabricated from aluminum (see photo above). I am at that point of buttoning up the motor for the last time . . . and am wondering if I should use 1JZ or 2JZ valve springs . . . . . has anyone here used these on their 1UZ, and if so, what mods are needed to do it right. I assume (ass - you - me ) the 1UZ valve springs are good to 7000 rpm.

Well . . . after much hand-wringing and midnight consternation, I realized that those standard 1UZ valve springs just weren't going to do the job. At only "42-46 pounds" of seat pressure, they are a tad too light for my high lift Kelford cams at my intended 7000 rpm shift points and at the quarter mile finish line. Kelford recommends "80+ pounds" seat pressure for the 201-T1 grind. So, what to do? The racer in me said to forget the standard used 2JZ springs -- mainly because I have no way to test them, and because they are rated at "62 pounds" of seat pressure -- so I bit the bullet and purchased a new set (32) of Brian Crower #BC1300 2JZ valve springs with this specification: "Spring Pressure: Seat: 1.325" @ 80 lbs / Open: 0.980" @ 158 lbs / Coil Bind: 0.810." I will use the standard 2JZ spring retainers (used) - no need for titanium at only 7000 rpm. Imagine finding a set of Brian Crower valve springs for a 1UZ in Bangkok! Thanks Khun Mac of MacTec . . . he has everything! It looks like my shop guy Art will be pulling the heads off, replacing the springs, and re-shimming those 32 valves one more time!
Some of the aftermarket 2JZ springs are over 100lb so I suppose you can find a close match using aftermarket sources. The 2j springs are extremely close in spec to the 1uz. has a link for upgrading springs under products or tech articles.
I spent yesterday down on the floor in the shop fitting the 1UZ V-8 into the Familia race truck chassis. A lot of time and care was taken to phase the drive line: after leveling the racer in all planes, a line was drawn on the floor that exactly passed through the centerline of the rear axle pinion yoke and the transmission output shaft before the engine was moved about so that the front of the crankshaft was also on this same line -- all of which are offset, as was the former 1.5JZ, for driver space, balance, and steering shaft clearance. The engine fit in the chassis very nicely, bolted up to the same trans mount, and, although it is tight, there is enough clearance for headers to clear the steering. Whew! There are more photos and text on my Racing Projects Blog.

It is nice to have an empty block and heads laying around the shop for this kind of work. The 1UZ was, until recently, considered a door stop in Bangkok! We did the math on the 1UZ and it came out that they are worth more as scrap aluminum by the kilo than as a running engine!
More work completed. Oil pan baffles with dip stick calibration and new braced oil pick-up tube fabricated, Brian Crower valve springs installed, aluminum firewall polished, and engine bay cleaned, sanded and detailed.
Yeah . . . . . you know . . . there is vibration . . . . the pick-up is trying to suck the pipe to the bottom of the pan . . . oil is thick . . . . and maybe I worked too long on a le Mans prototype class team where everything is built to last 24 hours at WOT!
I have been away from the shop for two weeks (in The States for a conference). In the meantime, my guys fabricated a mock-up of the Vortec V-9 supercharger brackets in aluminum and cardboard . . . to be transferred to steel once we are sure it all aligns. I may or may not want to brace the supercharger against the roll cage down tube (as in the photos below) . . . since I am using solid motor mounts.

I have since confirmed that, YES, the Subaru 'Pink" 565 injectors are a drop in for the 1UZ.