10 replies to this topic

[lx93]

hello fellow mazda racers,

I have a 96 SM that i had bought back in May and raced this past season, Since I am new to the SM racing and very inexperienced in working on my own car, I need some suggestions. The current motor in the car is at its end of life(low compression on no.4 piston and oil particles shooting out of the exhaust, and rattling around 2500rpm not lifter noise).

I want to keep the budget around 3000 with it installed, and what do you think is the best way to go about this? seems like the new rule dictates a stock head so i am assuming that the cost now of having a competitive motor is lower.

[Mike Collins]

Where r u?

[Mike Collins]

If you can R&R the motor on your own. Your local machine shop can do the motor for $1500-$2000 plus parts. Depending what you need another $1200-$1500.

[38bfast]

Just a caution. Make sure a local shop understands the rules. Many shops that aren't SM savay may do something ilegal per the rules without knowing. The other option would be a create motor from Mazda. Last I checked they still had some 1.8 available.

[38bfast]

The other option is a low milage salvage motor.

[Chris Ashcraft]

I would try and get a low mileage yard motor, why spend another 3000$ on a car that you are going to want to sell in a year to upgrade to a 99 or 01

[Mike Collins]

Don't let people scare you about building a motor. It's not that hard and yes a LOCAL (good quality) machine shop CAN do the motor on the cheap. It will be 95+% of a pro motor for less than half the cost.

[Brandon]

Not to take any business from local machine shops, but what is it particularly about your engine that you feel a need for a rebuild?

Are you getting a lot of leak-down?  Poor compression overall?  Burning a lot of oil?  Just some things to consider before spending a big chunk of change.

 

I'd be doing my own with a local machine shop but unfortunately other items are confiscating my time that I'd be putting towards R&R, disassembly/assembly, and all that...

There is one other option which may work out in the end: if you've got decent compression and your leak-down numbers aren't too far from the mark, you could just get a head done and swap that on.

About $2k is what I've heard from builders here in the NE.

 

As others have suggested, there are alternatives available however the pricing of used/salvage engines aren't quite like they were a few years ago where you could get a decent one for $300-400.

Or, at least up this-a-way in the NE that's been my findings.  Other parts of the country may still be like this but I'm not so sure...

 

It all boils down to three variables: quick, cheap, or easy - but you can only pick 2.

 

And don't let the nay-sayers get you down about 'blowing money on a NA1.8 vs. buying a 99+' - race what you own, have fun, and go from there.

[Jamz14]

I concur with Mike. Don't let anyone scare you out of going with your local shop to do some of the work. Not saying to go that way but don't let people tell you it has to be an SM "pro" shop in order to be competitive. I don't recommend just any old machine shop though. If you go to a well regarded racing machine shop, there is nothing in our rules that is complicated to understand for them. The biggest problem you will run into is whether a local race shop will have a torque plate for your car. My local shop ( Jim Grubbs Machining ) didn't have the needed plate. But these guys were so professional that they made the needed plate at no additional charge. They understood that having the correct tools allows them to expand their racing engine business to a new market with new customers for them. The boring and decking work cost me about $400 or so. I needed to provide my head gasket, crank, bearings and pistons along with my head measurements. This was machining only and didn't account for new rings, pistons bearings and gaskets. The head work well............... I would say that you are going to see plunge cuts allowed with clarification on concentricity and blending. The parts will cost you more than the machining. A good racing head shop will understand the rules. Doing the head work to comply is not hard or ambiguous unless you want it to be.

[LarryKing]

 

It all boils down to three variables: quick, cheap, or easy - but you can only pick 2.

 

Are you sure that's how that saying goes? - cause quick and easy kinda seem like the same thing to me.

[Keith Novak]

I've had very good results from a rebuilt bottom end with a pro head.

 

I go to a machine shop that is well versed in race motors but I talk with them about what's not legal for my class so we keep it simple.  For the block, I get it hot tanked, magnafluxed, cylinders deglazed, and I ask them to take as little off the deck as possible to get it flat.  Bringing everything completely stripped down runs me around $400 if I remember right.  If you want to polish the crank, it's another $60.  There are a few hundred $ in new parts for rings, bearings, freeze plugs, etc.  On my current motor, I actually reused the crank bearings and just cleaned them up with Brasso.  She spins smooooth.

 

With a $1500 pro head, I wind up with under $2500 into the motor and it puts out repsectable numbers.  With a new OEM or reconditioned head, the cost would obviously be less.  It won't win a Major but I can turn times .5 to 1 sec slower behind those who do win them despite my driving mistakes.  I'm only just now getting to the point where I can justify the cost of a bit more power.

 

I've also known people though who luck out with junkyard motors that are strong performers without even opening them up.  The rule of thumb there is they're always the fastest right before they blow up.