14 replies to this topic

[Brian]

I will be having a 1.8L engine installed in a 1992 originally 1.6L car.

This may be a silly question, but since the transmission will remain, does it matter which flywheel I use? If either a 1.6 flywheel or 1.8 flywheel can mate up with the transmission/clutch, does it matter which one I attache to the motor.

Is there a difference between a 1.8 flywheel and 1.6 flywheel other than weight and cost? Since the engine and transmission will be out of the car and separated (which will hopefully be an infrequent occurence) I am contemplating purchasing a lighter weigh flywheel (either the F1 Racing or Fidanza).

It seems that the flywheels for the 1.6 are lighter (which is what you want) and cheaper (which is good).

Am I missing something or am I a complete idiot? As you can probably tell, I'd rather drive a car than work on it (better for both me and the car)

Any thoughts and suggestions are appreciated.

Thanks,

Brian

[pat slattery]

Hopefully your not racing that in SM.

[JayF]

If this is for SM you need to read the rule book. Can't swap 1.8 into 1.6's and also cant use light weight flywheels.

[Glenn]

I will be having a 1.8L engine installed in a 1992 originally 1.6L car.

This may be a silly question, but since the transmission will remain, does it matter which flywheel I use? If either a 1.6 flywheel or 1.8 flywheel can mate up with the transmission/clutch, does it matter which one I attache to the motor.

Is there a difference between a 1.8 flywheel and 1.6 flywheel other than weight and cost? Since the engine and transmission will be out of the car and separated (which will hopefully be an infrequent occurence) I am contemplating purchasing a lighter weigh flywheel (either the F1 Racing or Fidanza).

It seems that the flywheels for the 1.6 are lighter (which is what you want) and cheaper (which is good).

Am I missing something or am I a complete idiot? As you can probably tell, I'd rather drive a car than work on it (better for both me and the car)

Any thoughts and suggestions are appreciated.

Thanks,

Brian

If this is a street car OK. You will also have to install a complete 1.8 wiring harness.....keep the 1.6 and build it up if you are looking for more power. Or Just build a 94/95. If this is a SM read the other posts, you will not be making any friends if you make the swap, and in any event NEVER post the mod here

[Brian]

I am aware of the SM rulebook. I will not be racing this in sanctioned SM events subject to all the rules stated above. I'm not that much of am idiot. This is just a fun track day car up against other 1.8s not subject to any true SM rules.

I have the Flyin' Miata conversion kit and motor mounts.

I just need to know what flywheel is needed. It appears from further reading that since I will be keeping the clutch and transmission from the 1.6 setup that I have to use the 1.6 flywheel. It seems that clutch and flywheel must match.

If that is the case, and since I have the motor and transmission out and apart anyway, I am better off replacing the clutch with the flywheel and if so am I better off going 1.8 or 1.6.

[Keith Novak]

It doesn't matter what trans you have. The flywheel, PP and clutch must all be the same, 1.6 or 1.8. I've put a 1.8 combo in a 1.6 so I'm sure you could put a 1.6 in a 1.8.

[davew]

You have to keep the clutch assemblies together. Flywheel, disc and pressure plate need to all come from either the 1.6 or the 1.8. But either assembly will work with either engine or either trans

Dave

[Brian]

That's what I was thinking after all the research done last night.

All 1.6 or all 1.8.

Any reason to choose one over the other? It seems the 1.8 clutch and flywheel are larger but the car won't have that much power or torque. I don't see any need for paying the extra money and having the extra weight of the 1.8.

[davecarama]

Any reason to choose one over the other? It seems the 1.8 clutch and flywheel are larger but the car won't have that much power or torque. I don't see any need for paying the extra money and having the extra weight of the 1.8.

This should most likely be in the ITA, TTE, area or even HPDE, but not Spec Miata.

Yes, leaving the smaller 1.6 disk, flywheel, pressure plate will be lighter. But they have smaller contact area, so you could risk having slower engagement / shifts and slipping.

If you are going through all of the trouble of swapping motors, you should spend the extra few hundred and get a new clutch (other wise, you might have to go back in sooner rather than later).

If you want an upgrade, why not get a nice Toda Racing flywheel and a stock pressure plate and a performance clutch disk? This way you are not going to put undue strain on the transmission with a super high pressure plate, and you will have a nice light flywheel, but not too light, and the Toda piece is a one piece chromoly unit, not an aluminum piece with contact plate inserts.

If you are trying to go on the cheap, run with what you have, if you have a 1.8 unit in good shape, I'd go with it.

Dave

[Glenn]

This should most likely be in the ITA, TTE, area or even HPDE, but not Spec Miata.

Yes, leaving the smaller 1.6 disk, flywheel, pressure plate will be lighter. But they have smaller contact area, so you could risk having slower engagement / shifts and slipping.

If you are going through all of the trouble of swapping motors, you should spend the extra few hundred and get a new clutch (other wise, you might have to go back in sooner rather than later).

If you want an upgrade, why not get a nice Toda Racing flywheel and a stock pressure plate and a performance clutch disk? This way you are not going to put undue strain on the transmission with a super high pressure plate, and you will have a nice light flywheel, but not too light, and the Toda piece is a one piece chromoly unit, not an aluminum piece with contact plate inserts.

If you are trying to go on the cheap, run with what you have, if you have a 1.8 unit in good shape, I'd go with it.

Dave

You can also have a local machine shop cut and balance the 1.8 and get it way lighter!

[Brian]

This should most likely be in the ITA, TTE, area or even HPDE, but not Spec Miata.

Yes, leaving the smaller 1.6 disk, flywheel, pressure plate will be lighter. But they have smaller contact area, so you could risk having slower engagement / shifts and slipping.

If you are going through all of the trouble of swapping motors, you should spend the extra few hundred and get a new clutch (other wise, you might have to go back in sooner rather than later).

If you want an upgrade, why not get a nice Toda Racing flywheel and a stock pressure plate and a performance clutch disk? This way you are not going to put undue strain on the transmission with a super high pressure plate, and you will have a nice light flywheel, but not too light, and the Toda piece is a one piece chromoly unit, not an aluminum piece with contact plate inserts.

If you are trying to go on the cheap, run with what you have, if you have a 1.8 unit in good shape, I'd go with it.

Dave

I'm not sure what ITA, TTE and HPDE mean. I assume the are other sections of this website.

Great idea about the clutch. I figured the same thing. Since I don't anticipate pulling the motor and transmission again anytime soon I decided now would be a good time to replace the clutch. I have decided to go with a new F1 Stage 1 clutch kit and F1 flywheel. I believe this is a good medium between going really cheap and going all out. If my mechanic pulls everything out and the current clutch looks fine (which I doubt it will) then I have a spare.

The new motor arrived today and the new clutch, flywheel, motor mounts and conversion kit arrive Friday so with any luck I will be back on the track next weekend.

[pitbull113]

unless this is a new or rebuilt engine replace the rear main seal and re-seal the oil pan as well before you install. When you do the clutch do the pilot bushing as well. Regardless of what the old clutch looks like toss it. Not worth the labor to install a used one.

[john mueller]

Go aftermarket lightweight

[dstevens]

I'm not sure what ITA, TTE and HPDE mean. I assume the are other sections of this website.

ITA is a wheel to wheel racing class, TTE is a time trials class and HPDE is a performance driving/track day class.

Where do you run, Spring Mountain?

[davecarama]

ITA is a wheel to wheel racing class, TTE is a time trials class and HPDE is a performance driving/track day class.

Yup, and the reason this question doesn't belong in Spec Miata section is because the cars are all set to the same "spec" and changing these parts (and motors) are illegal as per the class rules.

The other classes mentioned (IT and TT) allow for more modifications like these, and HPDE has no restrictions (well, maybe some don't allow things like NOS )

It is a little bit confusing, there is a NASA HPDE and a SCCA HPDE section, but no section really for other club HPDE conversations.