mx5cartalk.com

Still looking to buy my mx5, but ultimately it will get a turbo on it.

Just thinking ahead, which is the better motor for a more cost effective setup?

Are the costs similar to turbo each motor? Or is one drastically more expensive then the other? This would include rebuilding the motor too...

Is one easier to turbo?

Sorry if these questions are dumb, just trying to find the right car

Build a 1.8L.

Costs are identical. Forget rebuilding it.

Dann

Why forget the rebuild?

The B6 and BP last pretty well as long as they aren't abused (and even then they still put up a good fight)

You can buy a B6 or BP with plenty of life left in it for less than 1/3 the cost of a basic rebuild.

Ah I see...
Most motors are about $1000 on eBay?

So in a nutshell, there is absolutely no reason to conaider a 1.6 over the 1.8?

$1,000 seems to be the ebay default pricing, the same as they all seem to have exactly 99,000km on the clock.....

The prices are a fair bit cheaper in private sales (ie: guy smashed car at track and decides to part it out)

Nice post!

What makes the 1.8 a better choice? Just because you can get more power per psi you throw into it? Or are the internals actually stronger?

I ditched the idea of going turbo. After actually driving the car as it is.

Its a heap of fun!

Turbo is off the list for now

Read the miataturbo.com DIY turbo wiki.

The weak point is the rods which are identical among all B series mx5 engines. Same part number and all.

The 1.6 has a worse flowing head, less capacity by 250cc and late 1.8's have higher compression.

Dann

Edit: OP go drive a turbo one

NitroDann wrote:
The 1.6 has a worse flowing head, less capacity by 250cc and late 1.8's have higher compression.

Dann

Edit: OP go drive a turbo one

Could the head off a 1.8 be put onto the 1.6 as they are the same size bore aren't they with a different stroke? Or are the coolant channels and oil galleries different? Say if you were particularly determined to Rev a bit higher.

And yes OP go drive a turbo one. I could never go back to N/A now. Huge smile on my face every single time I drive it.

Dann, what is the cutover date / year for "late NA8s"? 1996 & 1997? Sometime in 1995?

badface wrote:

NitroDann wrote:
The 1.6 has a worse flowing head, less capacity by 250cc and late 1.8's have higher compression.

Dann

Edit: OP go drive a turbo one

Could the head off a 1.8 be put onto the 1.6 as they are the same size bore aren't they with a different stroke? Or are the coolant channels and oil galleries different? Say if you were particularly determined to Rev a bit higher.

And yes OP go drive a turbo one. I could never go back to N/A now. Huge smile on my face every single time I drive it.

No the bore spacing is longer on a 1.8.

Also why would you want to rev more when you can go faster? Thats like riding your sons pee wee 50 instead of your wr450 because the peewee revs more.

As for teh cutoff date, somewhere in 97 I think, make a new thread if you cant google it, heaps of people will know.

Dann

I don't want to Dann haha just wondering about the cross compatibility of the two engines

If you're buying an MX5 buy an NA8. Its a better car all round. More rigid & stronger drive line.
having said that. its a better base. If youre going to get 400 RWkW you'll have to rebuild everything anyway so it really doesn't make any difference. if you're looking at say 140rwkw or so. the NA8 would be a far better choice as a base car to start modding.

Thats not saying the NA6 is a bad car. There are lots of things which are stronger on an NA8 for medium mods.