HomemadeTurbo - DIY Turbo Forum - Some Pics Of My RX-7 Project

Hello everyone,

I've been lurking here for a while and thought it would be time to post a few pictures of my own ongoing turbo project.

Years ago I started out with a '86 NA RX-7 and decided to turbocharge the car using the HT-18 from the TII RX-7. That worked out quite well, though I got bored quickly and decided to start a more involved project. There are literally hundreds of pictures to this project and a lot of writeup. I'll post a few of more interesting pictures below.

If you want to read the whole project, you will find it on my website here:
http://www.aaroncake.net/rx-7/projecttina

Original turbo-NA setup with Hitachi HT-18, around 2002:

http://www.aaroncake.net/misc/turboi...%20Bay%202.jpg

http://www.aaroncake.net/misc/turboi...%20Bay%204.jpg

After about 15K of driving, I got bored with the roughly 250HP the stock turbo could provide, so I pulled the engine:

http://www.aaroncake.net/misc/rebuil...ger%20Side.jpg

...And disassembled it for porting and a rebuild.

http://www.aaroncake.net/misc/rebuil...emoved%202.jpg

http://www.aaroncake.net/misc/rebuil...ic%20Shaft.jpg

http://www.aaroncake.net/misc/rebuil...0Bench%201.jpg

The engine got a medium street port on the exhaust, and a small bridge on the intake. Small as far as bridgeports go, but it will do the job.

http://www.aaroncake.net/misc/rebuil...In%20Place.JPG

http://www.aaroncake.net/misc/rebuil...20Finished.JPG

http://www.aaroncake.net/misc/rebuil...te%20Plate.jpg

http://www.aaroncake.net/misc/rebuil...Bridgeport.jpg

With the internals prepared, it was time for assembly.

http://www.aaroncake.net/misc/rebuil...20Assemble.jpg

http://www.aaroncake.net/misc/rebuil...0Assembled.jpg

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

http://www.aaroncake.net/misc/rebuil...ont%20Iron.jpg

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

http://www.aaroncake.net/misc/rebuil...ing%20Legs.jpg

http://www.aaroncake.net/misc/rebuil...0Bolts%202.jpg

http://www.aaroncake.net/misc/rebuil...lug%20View.JPG

http://www.aaroncake.net/misc/rebuil...20View%202.JPG

The stock intake was really designed for NA applications and is very good at what it was designed for. But I wanted something more simple, better suited to the engine and unique. You can also see that the little stock turbo is currently installed. Since I had all the stuff to mount it already fabbed, I decided to use it for engine breakin.

http://www.aaroncake.net/misc/rebuil...y%20Runner.jpg

http://www.aaroncake.net/misc/rebuil...20Body%202.jpg

http://www.aaroncake.net/misc/rebuil...ont%20View.jpg

I needed some more fuel, so I built a new pickup assembly with an Aeromotive filter and AN bulkheads.

http://www.aaroncake.net/misc/rebuil...n%20Flange.jpg

The Aeromotive "700HP EFI Pump" was mounted underneath, plumbed with AN.

http://www.aaroncake.net/misc/rebuil...20Pump%201.jpg

A nice shot of the upper intake with the 1600CC secondary injectors installed. The primary injectors are 720CC.

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

The temporary downpipe. Just 2.5" SCH 40 pipe for the bends, regular old 2.5" exhaust tubing for the straight section.

http://www.aaroncake.net/misc/rebuil...e%20Welded.jpg

I built a new dual 2.5" stainless catback as well. Don't make fun of my mufflers, I love them and they sound great.

http://www.aaroncake.net/misc/rebuil...angers%201.jpg

The intercooler is a 24 x 14 x 3 unit. I modified the end tanks a bit to minimize cutting of the car and keep pipe length short.

http://www.aaroncake.net/misc/rebuil...20Brackets.jpg

http://www.aaroncake.net/misc/rebuil...0Extension.jpg

Stainless steel 2.5" intercooler piping:

http://www.aaroncake.net/misc/rebuil...d%20Tacked.jpg

http://www.aaroncake.net/misc/rebuil...0IC%20Pipe.jpg

http://www.aaroncake.net/misc/rebuil...et%20Pipes.jpg

http://www.aaroncake.net/misc/rebuil...h%20Welded.jpg

Here's the completed engine bay prior to the first startup.

http://www.aaroncake.net/misc/rebuil...ont%20View.jpg

The car was started on the first try and then taken around the block shortly after. Like any build, there were a few issues but for the most part things went well. The ECU is a Microtech LT8 which comes with a decent base map to get you started, but the map is really only suitable for getting the car running. Like any standalone, it needs to be fully tuned.

Here's the video of the first startup:
http://www.youtube.com/watch?v=5r4ksrUouo8

I drove the car for the remainder of the summer and basically tuned the light load and low boost areas. This was lots of fun, however the engine was not built to run the wussy stock turbo and the car was way too loud.

I called up ATP Turbo and ordered a GT4088R (dual ball bearing) with an 88MM compressor and 0.72 A/R housing, 77MM turbine wheel with a 1.06 hotside. The turbine inlet is divided TO4 and the outlet is a 3" v-band setup. Compressor inlet features the typical 4" "anti surge" design with a 2.5" outlet.

http://www.aaroncake.net/misc/rebuil...sor%20View.jpg

http://www.aaroncake.net/misc/rebuil...ide%20View.jpg

To mount the turbo, I of course had to build a manifold. The manifold needed a T4 flange and I used 2" SCH 10 304/316 stainless.

http://www.aaroncake.net/misc/rebuil...o%20Flange.jpg

http://www.aaroncake.net/misc/rebuil...to%20Place.jpg

http://www.aaroncake.net/misc/rebuil...o%20Flange.jpg

http://www.aaroncake.net/misc/rebuil...t%20Runner.jpg

http://www.aaroncake.net/misc/rebuil...gine%20Bay.jpg

http://www.aaroncake.net/misc/rebuil...y%20Welded.jpg

http://www.aaroncake.net/misc/rebuil...20Manifold.jpg

Next I had to make a 3.5" downpipe and 3" midpipe:

http://www.aaroncake.net/misc/rebuil...y%20Welded.jpg

http://www.aaroncake.net/misc/rebuil...0To%20Tack.jpg

The setup wouldn't be much good without a wastegate so the next task was to build a set of runners for the 44MM Tial.

http://www.aaroncake.net/misc/rebuil...%20Fitting.jpg

http://www.aaroncake.net/misc/rebuil...%20Runners.jpg

http://www.aaroncake.net/misc/rebuil...y%20Welded.jpg

http://www.aaroncake.net/misc/rebuil...ate%20Dump.jpg

With the major fabrication complete it was time for the little stuff. Turbo outlet pipe, new upper rad pipe, oil feed/drain, water feed and return, and a line to the wastegate.

http://www.aaroncake.net/misc/rebuil...In%20Place.jpg

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

http://www.aaroncake.net/misc/rebuil...0Installed.jpg

http://www.aaroncake.net/misc/rebuil...0Wastegate.jpg

And it was done! What a long journey. Aside from the few months of driving I had in the fall of 2006, the car was stuck in the garage from 2002 until basically the summer of 2007. It's so nice to be able to drive the car again. Here's a few pictures of the completed engine bay.

http://www.aaroncake.net/misc/rebuil...ver%20Side.jpg

http://www.aaroncake.net/misc/rebuil...ont%20View.jpg

http://www.aaroncake.net/misc/rebuil...ner%20Side.jpg

A few nights after the car was finished, I renewed the sticker and my insurance, installed an air filter and began driving it again. Over the next few weeks a friend and I spent some time tuning out the low load and low boost. Soon the car was far too fast to sanely or legally tune on the road so we booked some dyno time. After about an hour on the dyno, the car put down 387 RWHP at 279 FT-LBS with only 13 PSI of boost. The A/F ratios were fairly conservative and safe (11.5 until about 10 PSI, then falling to lower 11s around 13 PSI) with only 10 degrees of timing so there is a lot more torque to be made with a little more boost and a lot more timing.

http://www.aaroncake.net/rx-7/projecttina/dyno1.jpg

The dyno run on YouTube:
http://www.youtube.com/watch?v=nE4_BEgrKrc

A few weeks later I took the car to the 1/4 mile. I was hoping to see 11s but with an open diff and street tires, I don't think there's any hope. The best time so far is 13.1 at around 110 MPH with the tires spinning until 5th gear. Frankly, the car is dangerous to drive making nearly 400 HP to the wheels and having a weight of approximately 2450 LBs. It's going to be quite fun when I turn the boost up to around 18 PSI but by that time I'll have installed an LSD diff.

1/4 mile runs on YouTube:
http://www.youtube.com/watch?v=UOPXWf7_LQ8

If you've read this far I highly suggest you check out the link at the top to the full project. The writeup on my website has over 500 pictures and 100 pages of text to describe the entire process in glorious detail.