silicone_boy's 7 liter 1993 Mazda Miata
More info and pics to come soon...
hopefully!
I bought this pretty clean Miata on Ebay "accidentally". I put in a lowball bid and thought surely someone would outbid me. I woke up in the morning and found out I was the proud owner of a 1.6 Turbo Miata. Fortunately, it was in an adjacent state, so I flew out and drove it home. I really learned to like it. It had a performance suspension and was mildly boosted. I immediately started tuning it with a Megasquirt and turned up the boost. I also added a roll bar and drove it for about a summer that way.
Then I got the itch for more. Unfortunately, I started hanging out with the wrong crowd online: the "Engine Conversions" forum at Miata.net. Now, I had just got down putting an LS7 motor in a 1993 FD RX7. It is a monster with about 575 horsepower at the rear wheels. I had another LS7 (actually, it's a 427 LS engine based on a 7 liter LS7 block only set up for a wet sump) sitting in the garage. This was destined for a Factory Five GTM that I was going to build until the economy hit the skids.
I would stare at the Miata in the driveway and the LS7 in the garage. Then the bug hit me all of the sudden. On July 4th, 2009, I did the patriotic thing and ripped the Japanese motor out of the Miata
This is the beast that is going to go in it, backed up by a T56 transmission
I really like this picture...yes, 70 liters of displacement. That's like 30 times what it the stock motor has!
OK, I know, it's really 7 liters (or a 427 cubic incher in a small block package). It comes in the Z06 Vette. The car should weigh about 2550 pounds when it's done, or about what a turbo Miata weighs.
I know there are doubting Thomases out there who say it will throw off the balance, but I'm pushing the engine way back, and look how much the block, rotating assembly, heads, and tranny weighs (LS7 on left) vs a 1.6 Miata with tranny and with the turbo assembly removed:
Admittedly, the LS that I'm weighing above doesn't have an intake (its plastic) or accessories while the Miata engine is fully dressed. I won't have power steering or AC, so I figure the V8 should be right around 500 pounds. I plan on having a 50/50 weight distribution. For those of you who still think a V8 swap ruins the Miata's handling, I would refer you to Flyin Miata's website where they show Elvis, their test car with an LS motor. That particular car outruns just about everything they have ever put on their track except their Westfield 7's
To better distribute that weight, I will shove the engine as far back as it can go. You need to cut out some metal to make it fit anyway. In the picture below, I fit up the bellhousing to see how much metal to remove from the firewall. I want the bellhousing to be flush with the firewall, so I have some cutting to do:
You have to cut out some metal at the rear corners of the engine bay. Here's a shot of one side and then of both sides:
I then welded sheet metal over the defects and painted with POR15 (love that stuff). I still have some cleaning up to do of the welds but there should be plenty of room for the T56, which is a big tranny (it's ok that it's heavy...the weight is low and right in the middle of the car)
