Need new NA motor, Need Opinions
#1
Need new NA motor, Need Opinions
The Motor in my 99 is giving up the ghost slowly. It’s down on compression and burns 1-1.5 qtz of oil during a track day of 5 – 20 minute sessions. I’d like to get some opinions on my options. Cost if a factor as is timing. Just for reference My car sees 10-12 track days a year and mileage to and from the track.
Option 1: Rebuild 99 - $3200
Got a quote from a well known miata engine builder here in socal. Manly rods, balanced rotating assembly, oe 01+ pistons, bp5a intake cam, slight head shave, oe fasteners + bearings, oe oil pump, new timing belt, water pump etc etc. Double valve springs, conservative valve job. I would have to run this with the factory ECU until I had enough cash to buy an ecu later in the year.
Option 2: Purchase low mileage 01+ and MS ECU $2300-$2500
Just like it sounds. Buy a low mileage (50-75k) vvt motor and get a megasquirt ECU to run it and do the swap right off the bat.
Option 3: Buy MS now, Asspload 99 learning how to tune buy 01 motor this time next year $1000
I’ve got a lot to learn about tuning… maybe it’s best to just learn on a busted *** motor before I move to a larger dollar setup.
If it were your money, what would you do?
some more info: No plans on going FI. Not looking for dyno queen just reliable and some where in the 140-150whp ballpark.
Option 1: Rebuild 99 - $3200
Got a quote from a well known miata engine builder here in socal. Manly rods, balanced rotating assembly, oe 01+ pistons, bp5a intake cam, slight head shave, oe fasteners + bearings, oe oil pump, new timing belt, water pump etc etc. Double valve springs, conservative valve job. I would have to run this with the factory ECU until I had enough cash to buy an ecu later in the year.
Option 2: Purchase low mileage 01+ and MS ECU $2300-$2500
Just like it sounds. Buy a low mileage (50-75k) vvt motor and get a megasquirt ECU to run it and do the swap right off the bat.
Option 3: Buy MS now, Asspload 99 learning how to tune buy 01 motor this time next year $1000
I’ve got a lot to learn about tuning… maybe it’s best to just learn on a busted *** motor before I move to a larger dollar setup.
If it were your money, what would you do?
some more info: No plans on going FI. Not looking for dyno queen just reliable and some where in the 140-150whp ballpark.
#7
Cpt. Slow
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I'd say a combination of 1 and 3 actually. Or just option 3. Your tune would be kinda useless going from a broke *** stock '99 to a built brand new engine. And I'm not sure, no matter my tuning ability, I'd want to break in an engine on a fairly fresh tune.
But the engine, buy the MS, get the old engine running on the MS, swap engines, autotune on the way to your local tuner shop, and break it in on the dyno like a man.
But the engine, buy the MS, get the old engine running on the MS, swap engines, autotune on the way to your local tuner shop, and break it in on the dyno like a man.
#8
Option 1 here. I was in the same boat earlier this summer, went to the cheap solution and bought a used engine with 50k on it. Was good for 2 trackdays before it throw a rod. Lost à grand, many Time and few seals, gaskets and whatnot.
I sent the 99 engins for a full rebuilt and did upgrade a few parts at the same time. Now I have confidence in the motor and dont worry anymore. Sure it ain t cheap, but totally worth it. Ms3 add on and full on win and smiles!
I sent the 99 engins for a full rebuilt and did upgrade a few parts at the same time. Now I have confidence in the motor and dont worry anymore. Sure it ain t cheap, but totally worth it. Ms3 add on and full on win and smiles!
#9
Thanks for the opinions guys. To answer a few questions and close a few loops. I don't race this car, it's just for HPDE and TT. I "compete" in the socal miata challenge series in street class and I'm moving up to mod for next season.
I'm still on the fence on what to do about the motor. For now I'm going to purchase a ms3 basic from rev and start working my way through tuning the car. I'm fortunate to have a local support group with regards to the other miata challenge competitors helping me out.
The one PITA thing I have to deal with is that I street drive this car to the track. So i have to retain the ability to pass smog via OBD2 and Sniffer every other year. That means anything I do with regards to emissions equipment or ecu has to be un-done long enough to drive down to the check station and pass. That's definitely going to complicate things like COP's and stuff like that. I suppose I'll get the car up and running with the oem 99 ignition system and then start moving on from there.
For now the future plans are:
-ms3 basic now
-salvaged 01+ motor in a few months once I have the car working well enough on the busted *** motor
I'm still on the fence on what to do about the motor. For now I'm going to purchase a ms3 basic from rev and start working my way through tuning the car. I'm fortunate to have a local support group with regards to the other miata challenge competitors helping me out.
The one PITA thing I have to deal with is that I street drive this car to the track. So i have to retain the ability to pass smog via OBD2 and Sniffer every other year. That means anything I do with regards to emissions equipment or ecu has to be un-done long enough to drive down to the check station and pass. That's definitely going to complicate things like COP's and stuff like that. I suppose I'll get the car up and running with the oem 99 ignition system and then start moving on from there.
For now the future plans are:
-ms3 basic now
-salvaged 01+ motor in a few months once I have the car working well enough on the busted *** motor
#11
Instead of starting a new thread, I'm considering doing the same thing as option 1 but with a VVT engine. I'm not going to bother learning to tune on the 1.6 that I can turn over by hand and is pissing oil out the front crankshaft seal. I'm hoping I'll be able to find a base tune for a VVT engine that will be close enough to get the car running, then fine tune on the dyno.
Thoughts on this:
Manley
Stock used pistons
Light double springs
BE oil pump
SuperMiata or ATI damper
Cams
Deck head as much as possible with chosen cams
Thoughts on this:
Manley
Stock used pistons
Light double springs
BE oil pump
SuperMiata or ATI damper
Cams
Deck head as much as possible with chosen cams
#12
Elite Member
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Posts: 6,598
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Build a motor. If there is one thing I have learned, is that it's hard to trust a used/junkyard motor unless you personally saw it running and have confidence in the seller.
Otherwise it's a crap shoot.
Otherwise it's a crap shoot.
#13
Instead of starting a new thread, I'm considering doing the same thing as option 1 but with a VVT engine. I'm not going to bother learning to tune on the 1.6 that I can turn over by hand and is pissing oil out the front crankshaft seal. I'm hoping I'll be able to find a base tune for a VVT engine that will be close enough to get the car running, then fine tune on the dyno.
Thoughts on this:
Manley
Stock used pistons
Light double springs
BE oil pump
SuperMiata or ATI damper
Cams
Deck head as much as possible with chosen cams
Thoughts on this:
Manley
Stock used pistons
Light double springs
BE oil pump
SuperMiata or ATI damper
Cams
Deck head as much as possible with chosen cams
#14
The other thing you need to consider is getting idle worked out, A/C, etc. ie all the other **** the ECU does. It might be better to try that on the 1.6 instead of the VVT, rebuilt, turbo'd motor. The less items changed, the easier it will be to deal/understand a number of these issues that may/will come up.
I may do a 99-00 engine, it will basically depend on what I can find a good deal on close by.
#15
I would not recommend building a track car with stock pistons. N/A glory is obtained with as much compression as the fuel of your choice will allow. Save the head decking if you want even more compression later, or for future head re-freshening.
To really come up with a strategy, you first need to come up with a realistic budget.
To really come up with a strategy, you first need to come up with a realistic budget.
#16
I would not recommend building a track car with stock pistons. N/A glory is obtained with as much compression as the fuel of your choice will allow. Save the head decking if you want even more compression later, or for future head re-freshening.
To really come up with a strategy, you first need to come up with a realistic budget.
To really come up with a strategy, you first need to come up with a realistic budget.
1. I don't want to transport it to the track. Is it even legal for a civilian to carry say 50 gallons of E85 on a trailer anyway?
2. I don't want to be dependent on getting race fuel at the track, since they may be out, not have the right octance, etc etc.
If I was going E85, I'd probably be looking to go 13:1+ on comp
I didn't think pistons were the problem on NA builds, just the rods for going north of 7k.
#17
11:1 is perfectly streetable. I ran my 12:1 on the street occasionally on pump gas.
I am suggesting pistons for the power, and not so much the reliability. Although, the better pistons will be stronger than stock.
Trust me, you want all the compression you are comfortable with. Going with a higher compression piston now will give you a lot of breathing room if your thirst for power grows, and your budget allows for more later.
I am suggesting pistons for the power, and not so much the reliability. Although, the better pistons will be stronger than stock.
Trust me, you want all the compression you are comfortable with. Going with a higher compression piston now will give you a lot of breathing room if your thirst for power grows, and your budget allows for more later.
#18
Point taken. But I'm not looking to go past 11:1 since I'll be running on 91. We have a very few stations around here selling E85 but:
1. I don't want to transport it to the track. Is it even legal for a civilian to carry say 50 gallons of E85 on a trailer anyway?
2. I don't want to be dependent on getting race fuel at the track, since they may be out, not have the right octance, etc etc.
If I was going E85, I'd probably be looking to go 13:1+ on comp
I didn't think pistons were the problem on NA builds, just the rods for going north of 7k.
1. I don't want to transport it to the track. Is it even legal for a civilian to carry say 50 gallons of E85 on a trailer anyway?
2. I don't want to be dependent on getting race fuel at the track, since they may be out, not have the right octance, etc etc.
If I was going E85, I'd probably be looking to go 13:1+ on comp
I didn't think pistons were the problem on NA builds, just the rods for going north of 7k.