D Prepared Miata Build

ShhhhH! You keep talking like that and my wallet will hear!

Yes, all of those are planned, but that's going to be a year away (from the actual start of this build, which is most of a year away) at a minimum. Because I don't really have the budget for it, I haven't really done any heavy homework on the engine side of things yet.

Essentially the recipe is going to be high compression, light-weight rods & crank, ported head + bigger valves & stiffer valve springs, bigger cams and adjustable cam gears, ITBs and a bigger exhaust manifold. Not sure if it'll have to be custom, but the Maxim Works header may work too.

To start off, we're going to have a KCBHIW MegaSquirt on the current, fresh-stock-build + overbore engine (which, for a stock engine, is pretty stout) + an intake that eliminates the air meter, so that'll tack on a few extra horses and probably have us in the 125 WHP range.

Now for the racer's excuses: I'm going to be dealing with essentially a brand new race-car, plus moving from street tires to full on race slicks in a car that's going to be 300 lb lighter than anything I've driven. The last thing I need at that point anyway is 50 more horses to add to the mix. I say that now, I'm sure by the 3rd event I'll be wanting it haha
Are you sure you want the ITBs? You'll lose low torque doing that.
 
we'll see. Tuned properly it should be just as good as a manifold. My problem is finding a manifold that'll flow enough air.
 
yeah with correct horn and runner lengths the torque loss shouldnt be that great...the throttle response, more peak HP, the motor living at the top of the rev range, and the weight of the car should make any torque loss negligible anyway
 
we'll see. Tuned properly it should be just as good as a manifold. My problem is finding a manifold that'll flow enough air.

Two words: dynamic length. I have plans.
 
Two words: dynamic length. I have plans.

thats what its called, i knew it had a name its been so long since i read about it

remind me next time i see you muff to lend you a book i have that has alot of good info on this stuff
 
Two words: dynamic length. I have plans.

I look forward to seeing them come to fruition :)





Also, just to show how bad at math I am: 14x4 = 56. Not 48. And none of you folks caught it either, so shame you you ;)


But a 56 lb loss is is even better, so, woohoo sucking at math!


Last time I weighed the car it was 2027 - 56 = *starting* my D Prepared build at 1971 LBS. With literally no weight reduction done. Win!
 
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I look forward to seeing them come to fruition :)





Also, just to show how bad at math I am: 14x4 = 56. Not 48. And none of you folks caught it either, so shame you you ;)


But a 56 lb loss is is even better, so, woohoo sucking at math!


Last time I weighed the car it was 2027 - 56 = *starting* my D Prepared build at 1971 LBS. With literally no weight reduction done. Win!

is that with or without the driver?
 
Before:
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After:
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Front suspension clearance:
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Rear Suspension clearance:
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My problem now is that the jack isn't low enough to get out from under the car with the 13's. Whoops! I may need some ideas for a lower-profile one, or how to make this one lower profile lol. I'm considering getting another one and pulling off the casters. Or I may just have to travel with a few pieces of 2x6 to put under the 13s for tire changes lol
 
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My problem now is that the jack isn't low enough to get out from under the car with the 13's. Whoops! I may need some ideas for a lower-profile one, or how to make this one lower profile lol. I'm considering getting another one and pulling off the casters. Or I may just have to travel with a few pieces of 2x6 to put under the 13s for tire changes lol

hmmm i dont see you having suspension rubbing issues

Sucks about the jack i know harbour freight sells a lo pro jack except i believe its not aluminum like your current one.
 
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hmmm i dont see you having suspension rubbing issues

Nope, but that clearance will be a bit tighter once the 9.5s are in the pictures

Sucks about the jack i know harbour freight sells a lo pro jack except i believe its not aluminum like your current one.

Honestly I don't think it's that big an issue. I'm just going to need to keep a handful of 2x6 blocks around. If I keep them with the rest of my trailer stuff (tie downs, etc), it won't be a big deal.
 
I think I found the solution to my jack issue:

https://www.ebay.com (commissions earned)

plastic_car_ramp.jpg


It's not the absolute cheapest solution, but it's not *that* expensive and I think they'll be a bit more durable and easier on the tires than a set of 2x6" blocks to drive up on. Just throw 'em in the trunk or passenger seat of the Miata in transit, and keep them with the rest of the towing stuff (I plan on keeping these, the hitch (when not in use) and the tie down straps together in a tupperware box when not in use... because if I don't, I WILL lose stuff.
 
So what are potential interference points with the slicks? Once the tire deflects is it more likely to hit suspension bits or chassis?

I imagine you'll be able to dial back the negative camber a good bit too. Have you figured out how much you will need to change the spring/bar rates?

Sounds like we need a beer/brainstorming session. :D
 
So what are potential interference points with the slicks? Once the tire deflects is it more likely to hit suspension bits or chassis?

I imagine you'll be able to dial back the negative camber a good bit too. Have you figured out how much you will need to change the spring/bar rates?

Sounds like we need a beer/brainstorming session. :D

It's true. The problem, if there will be one, is the suspension (especially w/ the 9.5s, of which I should have a set coming after this weekend I think :D)

About the springs? No idea. They're already pretty high rates, I figure I'll see how it feels and go from there.
 
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Fun weekend project for the race car. Added about 12" of decking to the trailer. Currently, we can only fit about 1 1/2 tires on the decking because it's a bit wide. Didn't bring the decking up to the front because there's not really any support up there, and the miata's front tires sit over that cross beam. Also, if I brought the deck further back, getting to the D rings for the tie-downs would be more of a pain. I figured 6" forward of the cross bar was enough wiggle room and called it a day. The extra decking will make it a LOT easier to load, as it was a relatively nail biting experience. Now it'll be a lot less stressful (enough that I shouldn't have any problems loading it solo)


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6 lb Deka ETX9 battery ordered to replace the stock-type that's currently installed that weighs about a billion pounds. Very excite! :D
 
Battery + terminals was right around $70 IIRC. Reliable? So long as I keep it on a trickle charger (I have to do that currently, my battery's on the way out, which is why I finally got a light-weight one) between events, it'll be fine.
 
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