An End-of-build Retrospective on my Rx7 Evo GT by gmonsen | builds

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An End-of-build Retrospective on my Rx7 Evo GT by gmonsen

By diyauto

( 3 )

11 minute(s) of a 280 minute read

5-14-2013

The last finishing touches are in. The AST replacement is in, and the oil pre-mix tank is in where the ABS was, and the heat shielding is in. So, that's it.

These first 2 pictures pretty much show the engine bay as it is going to be.

These next 2 show the AST replacement, including the coolant hard line and the Hargett Quick Disconnect.

Here you can get a pretty good idea of all the replaced nuts and bolts with the Cy-Chrome Allen heads and acorn nuts. They are everywhere.

This last one shows the oil pre-mix reservoir.

Ceylon... I absolutely agree with one of your swaps. Can you guess which? I'll help you. I love the plastic oil cap. I actually think its an odd plastic. It looks and feels a lot like Bakelite, which is a favorite material of mine. So, the cap is a fun essential part of my "factory" look... So?

I noticed, and I'm sure a lot of others have as well, that the higher the standard you have for the main parts, the more you notice the ones you didn't improve as much. The little things are as time and money consuming as the big things. Maybe more so. And the more of them you "fix", the more the remaining ones stand out.

I will say that I had a very clear vision in my head of what the whole engine bay would look like when we got done. I had drawn out a lot of the parts and assemblies, if you will, over a few years and had the original version of the motor in there for several years to look at and think about. The only things that came out a little differently are the oil pre-mix reservoir, the AST replacement, and the heat shield, which I had completely ignored.

Josh... First, thanks for the nice compliments. They always mean a lot but mean even more coming from someone you know and respect. What I really want to see now is whether its what I think it should be. Whether its what I thought in my head when I decided to do all this. I had a lot of stuff I wanted to get in here, like the whole exhaust thing. A monstrously complex exhaust system with actively computer-controlled functions and all you see are the 2 exhaust tips in the bumper. And whether I could make "enough" power with a conservative, non-peripheral ported motor and whether that motor could be as reliable as it theoretically should. Can I get really good gas mileage? Will I worry at all about driving it on a moment's notice?

Second, I'll get some nice K&N filters. Third, I'm good with the red plug wires. My car is 80% black, 10% red, and 7.5% cream and 2.5% polished metal. Seriously. The only "violations" of that are the the "ZEAL" in blue on top of the shock towers and the gold on the heat shield. So, the red plug wires works okay for me.

5-15-2013

Car is more or less together. Down to little things like center caps on wheels and valve in OMP. But its running and Logan's driving it. Its being detailed tomorrow and they're going to try to take off the factory mudguards and polish a few bits. The original paint is probably getting a little tired.

Got some good videos. Both inside car and around it. I think Logan may have done some tuning, because it sounds better.

Only videos? Well, skip some of this. Just pictures and babble.

First, with a full tank of gas and my 60 pound bass speaker in the hatch, my car weighs 2900 pounds and 52.7% of the weight is on the back. Take away half a tank of gas at 70 pounds and my speaker enclosure and my weight is 2770 and still more than 50 on the rear even taking all 130 pounds off the rear weight only. Now, I added leather on every vinyl surface and sound deadening, and metal plated the plastic pieces, and I added a rotor and iron. And, I deleted the power steering, ABS, turbos, air bag, intercooler, hard pipes, wastegates, and downpipe. The net result is that my NA 3 rotor weighs the same as or slightly less (if stripped of ABS, air bags, and power steering) than the stock twin-turbo car.

The motor's done. There are a few small changes since the last posts. Mainly some pipes being painted black, the oil reservoir being mounted where the abs was and a few other small things.

The car has may a year's dust on it which will all be fixed in the next day. I still wanted some pictures of the outside of it to start to see what it looks like overall.

http://s254.photobucket.com/user/fd20na/media/Gordon%2520R1%2520files/GOPR0061.mp4.html

And here's Logan pulling away...

http://s254.photobucket.com/user/fd20na/media/Gordon%2520R1%2520files/GOPR0062.mp4.html

Bwarrrrrp... I probably have an earlier era definition in mind if you're wondering about the GT moniker in the title. Without going into origins I think 1950's Maserati A6's, 60's Ferrari Lusso's, 330 GTC's, most Astons till late 70's and today again are all GT's in the classic sense. Ferrari's Maranello stands out among their recent cars. But the earlier Ferrari GT's were much more track oriented than today's on a relative basis. Really nicely done interiors, but very simple. Meanwhile, the bodies were relatively lightweight and they had great engines. So, I'm not talking today's exotics, but I'd still put the 370Z a step down from what I'm talking about. I'm kind of partial to Vettes having had 2 C4's and think the new Vette qualifies as a GT, because they seem to have finally raised the interior to Cadillac levels. And, that's what I was doing here in redoing the interior the way I did to match the motor sort of.

Hey, Prometheus, I haven't seen your name on many posts recently? Good to hear from you and glad you like where it went.

Now, here's the thing. Below is my favorite video for obvious reasons. I just play it over and over again. However, Logan never revs it over 5000 rpm, so, for now, you have to imagine what it sound like at 8800 rpm. Also, the cutout valve for the second exhaust pipe is not hooked up to the ecu and is in the closed position, so, the sound is muffled a bit. Still, I can tell that the exhaust and dual tip muffler box back there really worked to deepen the sound tone. Other guys with 20b's will comment on the issue of mufflers and sound I'm sure. Anyway, here's what is ultimately a tease for me, but is very encouraging.

http://s254.photobucket.com/user/fd20na/media/Gordon%2520R1%2520files/GOPR0056.mp4.html

5-16-2013

Rxmfn7... The one thing I can tell you is it seems to be worth the wait! The easy sound of the motor is very reassuring. It seems very comfortable cruising or getting on it. Very loose.

RCCAZ1... Its very hard to express what I am feeling right now. I put a lot of myself into this and had been frankly disappointed with the car and couldn't understand why it wasn't turning out to be what I thought it should be. The idea was a detuned 3 rotor NA race motor that was refined and civilized and yet sounded great when you got on it and made 350-400 rwhp. The idea was that it would be completely reliable, because it was NA and what happens? I get the car done and a bearing seizes necessitating a complete rebuild and almost another year and almost the same money again, minus the cost of the longblock. Now, with this build, I am sure I have what I wanted and thought I could make and Logan deserves a lot of praise for making this happen. He understands these motors unlike anyone else I have run into. Roger Mandeville and Carlos Lopez have been the best known NA 3 rotor motor builders and deserve their reputations. I know both of them to talk to and Roger clearanced and balanced this motor. Carlos has explained a lot of things to me over time and I know Logan has spent a lot of time with both of these guys. Logan is the next generation of really sophisticated multi-rotor builders. Anyway, I love the way it sounds both for the aural pleasure and for how the mechanicals sound. They sound really good. Its a good motor.

Thanks, Matt724... It will go on the dyno Monday morning and we'll see what it makes. I'm trying to document everything. I'm sure the numbers will be satisfactory and somewhere in the broad range I am expecting. I'm pretty sure from having driven Logan's 400+ whp car and my car with its earlier NA motor that the power is going to be all I will need or want. We'll also have it on the track at Virginia International Raceway Monday afternoon doing laps with a variety of other FD's powered by stock twins, single turbo 13b's, a single turbo 20b, a Formula Mazda 13b NA, and a 4 rotor NA. So, we'll get a good idea where the NA 20b fits in terms of handling on a track.

You know, I can just listen to the video of Logan driving the car and get goosebumps, but I realize that many people on here have never heard an NA rotary other than maybe a 787b video. The sound of the motor is so different than the sound of a 13b single turbo or the stock twin turbo powered cars, but its the motor I think the FD was always meant to have. And Logan says it sounds epic...