B6ze NA cookbook :)

[Timmyd865]

Hey guys. I went out and bought this book "Mazda Mita: Performance Handbook, by Norman H. Garrett 3rd." I found it interesting that it had a lot of help with the B6 block and hints for tuning it. So I've read the whole thing many times (engine section that is) Here is a good way in my opinion to make a possible 130 plus hp w/the B6ze.
1. buy an S-AFC for fuel controlling
2. buy an Air/Fuel ratio gauge
3. find a used head
4. port and polish the head at home (at least port match and get rid of any obvious blemishes)
5. upgrade valve-springs (volvo 90's?!?! any word on that, i hear they can be used)
6. corksport camshafts
7. Mill the head 0.15 inches to increase compression ratio to 10.5 to 1
8. * BRILLIANT IDEA I THINK * - while flipping through the book and exhaust sections, they showed me that the stock 1.6 liter engine has a stainless steal header. Now this header collects after about 1 foot, and is angled twards the back of the miata (the driver side for our car), now this means, where it collects you're gonna hafta bend a new pipe to mate it up to ur current down pipe. But this would be a good solution for a header. I think. I'm pretty sure it should bolt up to our head, same head... right? <p> **Here's a toughy question for those who know a lot What's the current valve clearance? Cause a new camshaft will prob. have about .250-.260 lift, and I want to mill the head. So what's the most I could mill the head if say i found camshafts with .260 lift? I'd still like to up my compression ratio to AT LEAST 10:1 with out touching the bottom end. This book states pretty clearly that you don't need to play with the bottom end unless you need to fix something. These engines should be able to rev up to 8.5k on a stock crank and pistons, and do it saftly.
** NOW one MORE thing! How to remove the fuel cut. I know that doing all this to my engine would shift the power ban up at least 1k, so there for i'd want to go to at least 7k or 7.5k redline. With upgraded valve springs this should be a safe redline. Anyone know how to crack the fuel cut?<p> AHHH one more thing.. anyone have a wiring diagram for the SAFC? Has anyone got it to run right yet? I think that is the FIRST thing I'm gonna do, just incase I decide to boot the NA tuning, the SAFC can be used for almost anything, or say I give up on the whole car, i can still sell the SAFC or keep it for ANY car. So I have my mind made up on starting the project with an SAFC. And ebay's selling the new SAFC 2's for like under 300 bux! Sounds like a deal to me!!! Any thoughts?
WELL tell me what you think, and answer those two big questions Thanx guys!<p>[ August 18, 2003: Message edited by: Timmyd865 ]</p>

[Timmyd865]

BUMP ^
COME ON GUYS! Someone has to know sum of this stuff.. and have an opinion!!!

[maldo]

130hp on a 1.6L, get ready to spend at least $10000.<p>1st off, get rid of the S-AFC, you need either a TEC-III or a Haltec. Personally, I would go with a TEC-III as it offers greater control, price with injectors is $2800usd. Worth every penny. (also removes the fuel cut)<p>An A/F gauge is all but useless, get an EGT gauge first.<p>Don't port the head yourself if you don't know what you are doing. If you go hogging out the ports you will ruin the velocity for an NA engine. The only thing you should be doing yourself is a simple port match using the gasket.<p>The Volvo VS-855 springs will work althought they aren't really required unless you are planning on higher lift cams and higher rpms. They are also next to impossible to find, last time I looked they were unavailable thru any of the dealers. A better option is to buy a '99 Miata head and transfer the valvetrain to your head as you gain the benefit of solid lifters and stiffer springs. $400-$500usd for a head. As for cams, TODA makes some great NA cams for $400usd a piece. Another option is to get BOIG to make you some. I don't think the corksport cams are really worth it, especially if they don't advertise their specs.<p>The header idea won't work as it would end up going to the tranny side. There is no room under there. Best option is to get a custom one made.<p>For the revs you will want to get to in NA trim, you will want to lighten the reciprocating mass (ie, crank, pulleys, flywheel). If you are just going to 7500rpm then you would want stiffer valve springs which are available in the '99 head. Anything higher and you will want a billet main center cap to reduce the tendency for the crank to twist/vibrate at the higher rpms.<p>There is a lot more to it than slapping together a few components, everything needs to work together. That is the only way you will ever be able to get 130whp or more in NA trim. The stock ecu must go and you cannot use a piggyback. If you want it to be streetable, 130hp would be a max and I would think you would want 12:1cr or close to. Randy is only getting about 147rwhp in his BP NA street machine and that is with an IRTB settup and lots of little tricks.<p>You need to do more research. Go to www.miataforum.com and do some searchs in the power forum. Don't post until you do a lot of research and check the archived threads as they will eat you alive.