D Prepared Miata Build

nope, unfortunately. I actually asked Kevin about that a month or 2 back haha
 
nope, unfortunately. I actually asked Kevin about that a month or 2 back haha

i was going to say most of the recent gains have been due to the vvt setup which would have been awesome on the b6...ohh well i would say great minds think alike but this is me and you we are talking about
 
Ok, yeah. With that formula, I'd agree with you. 200 lbs is a lot to overcome on an autocross course.

Maybe I'm retarded, maybe I'm a genius...maybe I'm some kind of retard genius...but what would it take to reduce the displacement on a VVT 1.8 by .113 L? Get some sleeves machined and reduce the stroke a bit? I know Japan/Europe had a 1.6 for longer than we did, and in P you can use a JDM block. Any chance there was an NB with a VVT 1.6?




I'm going with retard genius.
 
Ok, yeah. With that formula, I'd agree with you. 200 lbs is a lot to overcome on an autocross course.

Maybe I'm retarded, maybe I'm a genius...maybe I'm some kind of retard genius...but what would it take to reduce the displacement on a VVT 1.8 by .113 L? Get some sleeves machined and reduce the stroke a bit? I know Japan/Europe had a 1.6 for longer than we did, and in P you can use a JDM block. Any chance there was an NB with a VVT 1.6?




I'm going with retard genius.

it would still be a 1.8l block and classified as such i think. It would be like boring out the 1.6L...it technically still a 1.6, underboring a 1.8l would still classify it as a 1.8L
 
My head

spy.jpg


asplode
 
it would still be a 1.8l block and classified as such i think. It would be like boring out the 1.6L...it technically still a 1.6, underboring a 1.8l would still classify it as a 1.8L

No, it would be like boring out the 1.6...technically, they're going to count it as whatever the displacement is once you're done. (kiss)
 
No, it would be like boring out the 1.6...technically, they're going to count it as whatever the displacement is once you're done. (kiss)

...unless they are going to force you to tear down the engine my guess is they verify it by the block. and per the earlier rule muff posted boring is legal
 
...unless they are going to force you to tear down the engine my guess is they verify it by the block. and per the earlier rule muff posted boring is legal

At Nats, I believe CP guys last year were expected to bring all the gaskets and whatever they might need for a teardown. Could happen. If somebody protested, it definitely could happen.
 
...unless they are going to force you to tear down the engine my guess is they verify it by the block. and per the earlier rule muff posted boring is legal

They have tools to measure bore and stroke without taking the head off. They do occasionally spot check at the big events to keep folks honest in the P/M classes specifically

Also, while boring (to an extent) is specifically allowed, I don't think "de-boring" (can you even do that?) is.

EDIT: And tear downs for protests have happened. It's part of racing. At least it's not like club racing where if you podium there's a very high likely hood that a rebuild is in your future
 
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Also, while boring (to an extent) is specifically allowed, I don't think "de-boring" (can you even do that?) is.

If it's not, de-stroking definitely is.

If you told me to pick one person who needs less stroke...Muff. Without even thinking about it. :p
 
Hmmm...maybe not?

2. Cylinder sleeves may be fitted to the block for repair purposes
if they serve no other prohibited function. Sleeving may
not be used to create a new engine configuration (one which
exhibits the same displacement as an allowed engine, but
which has differing bore and stroke), unless authorized in
Appendix A.
Oil passages may be enlarged, restricted, or
plugged.

1. The crankshaft may be replaced with another of the same
basic material, provided the angles of the crank throws remain
the same. No change in stroke is permitted unless
authorized in Appendix A.
 
Yeah, I knew about the stroke rule but obviously glanced past the sleeving rule. On the upside: Knife-edged crank! :D

Also, someone buy me this for christmas:

949racing_725_twin_clutch.jpg
 
Also, someone buy me this for christmas:

949racing_725_twin_clutch.jpg

I was going to say "Sure, how much?" then went and checked.

Holy effing ess! That's an expensive clutch. Want to bring that up the next time somebody brings up how they think we should be able to change clutches and flywheels in ST*?
 
They have tools to measure bore and stroke without taking the head off. They do occasionally spot check at the big events to keep folks honest in the P/M classes specifically

Also, while boring (to an extent) is specifically allowed, I don't think "de-boring" (can you even do that?) is.

EDIT: And tear downs for protests have happened. It's part of racing. At least it's not like club racing where if you podium there's a very high likely hood that a rebuild is in your future

ok you have my interest...how do you measure the bore with the head still on the car?

And i know tear down protests can happen but block identification could cut down hugely on having to.
 
I was going to say "Sure, how much?" then went and checked.

Holy effing ess! That's an expensive clutch. Want to bring that up the next time somebody brings up how they think we should be able to change clutches and flywheels in ST*?

Yeah... but it's also the lightest readily available clutch / flywheel I've been able to find. 14 lbs for the combo is IIRC just over half what the stock flywheel weighs by itself.

And i know tear down protests can happen but block identification could cut down hugely on having to.

Stroke I imagine is pretty easy to check with the head on, but I don't know what the specifics of how they check the bore diameter. I do know the tools were broken out last year @ Solo Nats to verify compliance in at least 1 of the P/M classes. IIRC there was a piece that mentioned it in the SCCA's magazine. I believe that Solo borrowed them from the club-racing scruitineering folks and they were saying how happy they were to be able to have access to these as it made this check really easy, instead of having to have the heads off the cars.
 
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Thoughts? Is there any reason even with a high comp engine & worked head and manifold I'd need to go bigger than 2.5"? I know there's a bunch of you that know your engine theory a lot better than I do so I'm open to suggestions. I was playing around on Summit's site last night and came up with this as what I think to be a workable, budget friendly solution that shouldn't hurt performance and still keep me within the Atlanta region's sounds limits. For the record, both mufflers are straight-through, perforated tube designs

psm-82-4216_w.jpg

http://www.summitracing.com/parts/PSM-82-4216/

to

wlk-15038_w.jpg

http://www.summitracing.com/parts/WLK-15038/?rtype=10

to

wlk-24215.jpg

http://www.summitracing.com/parts/WLK-24215/?rtype=10

to

wlk-17230_w.jpg

http://www.summitracing.com/parts/WLK-17230/?rtype=10

to

th9911336HKR.jpg



And you may ask "why run a cat?" and I'll pose this in response: Why not run a cat. Modern cats have been shown to have minimal, if any effect on performance, and also: how funny would it be to have a serious race car with a current registration on it? lol. And there's no reason we can't try to be a bit more environmentally friendly ;)
 
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