Hello,

I am trying to decide on my first project Miata.i am planning to adding a T25 turbo and using the car for autocross and fun. I have been looking on the forums trying to decide what is the better engine to do this to? Can anybody point me in a direction so I can decide. I know the 1.8 will have more power but is it a ton more? Is one engine able to handle the power better than another?

Thank you for your help and knowledge

 

1.8

All 1.6 arguments are invalid.

/thread

 

Why though? What makes the 1.8 so great? Not to sound rude I just want to know

 

If you're building a motor, materials cost about the same. If anything there's more support for the 1.8. More torque. More power. More.

 

Thank you. I guess I need to decide on weather or not I want the more haha is it a ton more? I thought it was maybe 10 hp more

 

"There's no replacement for displacement". The 1.8 is 12% more displacement, and any mod you make to the 1.6 you can also make to the 1.8, it'll always be 12% ahead. That's ignoring other differences like there being better head geometry and VVT available in the 1.8 that were never put into the 1.6 (at least, not in the US).

The theoretical advantages of the 1.6 are slim:

- it's cheaper to use a working motor that's in the car than to swap over a 1.8. (note that this only applies as long as you're not making significant mods to it)

- the 1.6 is a bit lighter

- classing rules for some theoretical race class might favor less displacement

--Ian

 

It's not just the engine. Do more research.

Diff, brakes, tps, chassis, axles, TB, torsen, AFM, intake ports, alternator, and interior parts are all improved. There's more.

1.8

/thread.

 

Do you already have a car? If not, starting with a 1.8 car is way better.

 

I do not have the car already I am trying to decide which is the better base car to start with. I forgot about the diff on the 1.8

 

Find a 94 and start there, unless you like the look of the NB's better. Then get a 01-05 non-msm, for vvt goodness.

94-95.5 are OBDI and the easiest to get through emissions testing if you have that.

 

Did you forget about having to retrofit a variable TPS?

How about short nose crankshaft problems?

 

Everything mentioned in this thread is irrelevant because it really boils down to the alternator. You don't hear anyone upgrading to a 1.6L alternator. 1.6L alternators are dink, ergo get a 1.8L. That's the only reason why a 1.8 is favored. Don't let these e-thugs yank you around.

 

I thought the 1.6 starter was the weak link?
Kind of offset by the superior 4.3 rear end ratio and all...

 

If you are smart the cost of turbo between a 1.6 and 1.8 is the cost of the manifold, nearly every other thing on a stock bottom end build will swap over just fine.

There's still another $1500 in upgrades you probably need on a 1.6, 1K for a torsen swap, another 500 in clutch a 1.8 would need anyway.

My 1.6 car were nearly free, all salvage and ****. I have fun with it, spends less time busted than 1.8 power chasers...

 

buuurned

i see what you did tere

 

Thank you for all the information guys!!

 

the 1.6L is like Justin Bieber's *****; it's fine, but it's nothing special. It would take a lot of money to make perform as well a black man's from birth.

 

It depends on your starting car, cost, and goals.

I got a super cheap (almost free) 1.6L car with some crank wobble. You can buy good 1.6L motors all day long for like $200, running, with accessories. 1.8l motors tend to be a bit more expensive. The modding cost is roughly the same if you start with a base on both ends. I built an RX7 diff for my car with a total cost of about $250. This is the clutch type LSD which many here hate. I have also pieced an almost complete turbo/kit for roughly $1200. This process has taken me a bit over a year and has me on here looking for used parts about 3 times a day. With all that said the 1.6 is going to make decent power and be relatively inexpensive, but if I could do it over again. A 94 car with the torsen is what I would do.

Two piece axles, torsen, bigger motor, no AFM, better head...ect.

 

I run and race a 1.6. ther is nothing wrong woth them, they are cheap and make oka power.

If you had a 1.6 already I would say carry on with what you've got BUT you dont, so I agree with the others. Start with the 1.8. for reasons mentioned above. Stronger AND Torsen Diff. Bigger clutch, better brakes, TPS etc.

 

Nobody with a 1.8L wishes they had a 1.6L.