Spec Miata Project

The donor car is a 1990 Miata with 120K miles on it. Body is close to perfect and it's running well. (Almost hate to do this to it. <g>)

The plan is to pull the engine and trans and rebuild the engine here. The trans will get shipped out for a rebuild.  Before doing anything, we wanted to base line the rear wheel HP, to see what we had.  Two inertia runs back to back came in at 96+ HP at 6400 RPM, with 88 lbs of torque at 5000 RPM.  Considering this engine had 120K miles on it, with stock intake, filters, etc that wasn't too bad. Note that the A/F ratio is extremely rich at WOT.  The new intake duct, filter set, etc, will probably correct this. If not, we may have to do some MAF box swapping (g). A/F Tuning alone might bring this engine up to 100+ hp.

BTW, We have dyno'd several Spec Miata's, with home built rebuilds and "pro built" motors. ($7000).  They all put about 107-109 HP down to the wheels. If you are capable of building your own give it a try. You will save $5000 and have just as much HP as the pro built motors. (Unless you want us to do it. We are more reasonable and can get you maximum HP.)

 Plan is to have this thing ready for at least the spring. But MAYBE a test day in Florida sometime before then.


HP/Torque Graph


Nice looking Florida Car. (L).      Randy (owner) like a deer in the headlights. (R)
 


Engine is out.

Other items to be installed:


Engine after clean up and partial assembly.

 

 

 

Interior safety systems under construction. Randy (the owner) did the roll cage and cleaned up and prepped most of the interior of the car. He did a real good job. It was nice working on such a clean car.

We went with a 10lb fire system and xxxxx seat and a 14" convex LongAcre mirror.

 

 

 

 

 

Final work on the engine. Actually the only problems we had were small.  A couple missed vacuum lines, and that was about it.

 

 

 

 

 

 

 

And best of all.   Look at our dyno run after the rebuild.  This is with the break-in 10W30 Non Synthetic with a cold gear box and diff.  113 HP at 6400 RPM and we have at least one valve lifter that is slightly worn. We will be fixing that after Randy does his SCCA School and track day. 

About 40 days from start to finish and most of that was waiting for the transmission to come back from the re-builder.  We and (most important of all) Randy are really happy with this project. It has been a fun one.

Give us a call if you would like to get into a Spec Miata.

 

 

 

Here it is completed on it's way to VIR.  It did well.   Ran a 3 day school and not a single problem. Randy, drove it to a 6th place finish in the final day race of 35 other Miatas.