pros/cons 1.6L vs 1.8L
 

*****P.S. - I searched before I posted this thread, and was not able to come up with much/if any useful information about 1.6L potential. Most of the threads jump the instant answer~ swap a 1.8L!*******

Hi, new to the forums, and while i currently dont own a miata, i am in the process of acquiring one. I am looking to get an NA and as you all know, the 89-93 got the 1.6 L (98 cu in) B6ZE(RS) I4, and the 94-97 got the 1.8 L (110 cu in) BP I4. Due to my impossibly low funds, i will most likely end up with a clean 1.6l. Thus, i would like to know how much potential the 1.6l has when being boosted. The reason being i will most likely keep the 1.6L and build it. I would like an ultimate power goal of 250~275whp.

1) So how much power can the stock 1.6L handle on stock internals (Bottom/Top End)?

2) With a basic bottom end rebuild rebuild ~ Low comp forged pistons, forged H-beam style rods, rod bolts, head studs~ Can the block safely support upwards of 300hwp?

3) Since i have been lurking the forums for a while, i have noticed that many of you are avid users of MS/Hydra, is there a reason for this? Many of my friends who have turbo applications have used Greddy emanage or AEM F/IC with great results. Do MS/Hydra have specific features that make them more user friendly with miatas?

Thanks

Stock blocks are bulletproof to 200whp, fairly safe to 250, marginal above that, time bombs above 300whp.

Your budget restrictions confuse me - you don't have the money to swap a 1.8 liter motor into your car, or buy a car with a 1.8 liter motor, but you have $2k to dump into a shortblock build? The ONLY reason to build a 1.6 is convenience - you already have it, you already have a turbo manifold for a 1.6, etc, etc. The 1.8 is a superior motor - you get more power, more displacement, better spool, ability to use the BP4W or VVT heads. Every time I drive a 1.6 car the decrease in spool really surprises me - the 1.8 cars spool sooner and smoother every time, no matter what turbo. There's no replacement for displacement.

If you don't have a car yet, you'd be a fool to even consider buying a 1.6 and then building the motor in it. Even if you do end up with a clean 1.6 shell, you'll want to replace the motor with a 1.8 before you build it. You'll also need to swap the rear end for the 1.8 rear end, and the 5-speed tranny won't last long at 250whp either.

In reality, what you want to start with is an early 1.8 car, a '94 or a '95. You get the 1.8 motor and the stronger diff to start off, plus larger brakes.

We all use MS because it's got great support. Hydra has great support as well. E-Manage and AEM FIC are both piggyback units, neither has any support to speak of and neither has the capability of the MS or the Hydra.

Thanks savington. What i meant was that it would be more convenient to build the 1.6L if i already had it. For some reason i thought that if you had the same size turbo, such as a T25 on both motors, running the same amount of boost, the larger displacement motor will have marginally better low end spool response, but choke out on the top end. Anyways, due to the fact that im not very knowledgeable, and the fact that i have seen your car in videos (bitch is beast, your obviously doing something right) i will take your word for it and try to snag a 1.8L regardless. Thanks for the fast respond time. But for the sake of knowing, how much of a difference would there be in response time in spooling for the 1.6? Also due to the fact that it will be a street car, would a 250whp 1.6L still spool fast and be quick enough, that i wouldn't regret it all together? Once again this is all what if.

Thanks

The 1.8 will have that little bit more torque avaliable down low that the 1.6 just doesn't have, if you turbo it or not. I own a 1.6 and 1.8, non-turbo as of now. I love my 1.6 but my wifes 1.8 just feels more ballsy with the extra torque. I am sure this extra torque and the ability to get more air moving at a lower rpm will help the turbo get up to speed and spooled quicker. This discussion has been done several times and it always seems to end with, if you want ultimate power, get the 1.8. If you just want to add some more with a turbo, a 1.6 will be fine. A little added boost on a 1.6 can make up for most of the power difference between the two.
I am personally building a 1.8 to go into my 91. It started as just a 1.8 swap but now it will be getting a MSM turbo as well. I know, I know, please don't knock on the idea. I got it cheap and I have very modest power goals with a prioriry being reliability.
Also if you buy a 1.6 car you will have to at a minimum upgrade the differential, axels and driveshaft to the larger 1.8 stuff. That in itself can be as much as $1k if you get a torsen at the same time.
Having bought both, I would say go with the 94 and later. For the $500-$1000 difference in price for a similar condition car you will get a much better specimen for future endeavors. The later ones are a tad heavier, but come with additional bracing in most cases and some of the earlier bugs worked out.
Either one is a blast. You just have to ask yourself what you are really looking for.

Stock block 1.6 with 2554 or 2560R for the street is a beast, you are at boost threshold at all times at highway speeds. The 220whp you will get with the stock 1.6/2560R is relatively/very safe if tuned correctly, and if the car already has the motor this is the way to go if you have an impossibly low budget, or whatever you said. If you launch it hard, the word is that the 1.6 rear end will lunch itself, but I'll bet if it's just a daily streeter, you'd be ok. Be realistic with what you can get for what budget you have. Stay n/a and work with MS, suspension, brakes first if you are poor.

we know

Glad to see you came back out from under your rock.

Check kayak thread, he was hugging the rock, in a river in Arkansas, waiting for the hillbillies to show up. Not that he wasn't going to enjoy it...


OP

Stick with a simple plan, or go all out. There is a black hole in between that swallows money with varied results.

Put the most you can afford into a good platform. The turbo costs are all the same. For the 1.6Ls you'll see cheap stuff like Greddy or old FM parts. 1.8L always has the option of someone's junked MSM setup. Either way, it will be much more expensive to turn a base car into something better down the road than just starting with a good car. 1.8L preferred for stronger parts, but my 6" 1.6L diff held up to a lot of abuse at just under 200whp on the street. YMMV

It was a busy week:
http://hphotos-snc3.fbcdn.net/hs553....5_326830_n.jpg

1.6L = n00b


if anyone else tells you different, they weren't smart enough to work off a 1.8L platform.

As for hugging a rock...well, I did urinate on a goat.

Interesting.. I first read that as cock not rock....

Everyone shut up, I'm looking for braineysack's build thread....

:giggle:

braineack = n00b

Thanks for the perspectives people, based off the answers i will try my best to get 94-95 so i can get the 1.8L, but if for some reason i get an amazing deal on a 1.6L car i will have to do some thinking on whether or not to get the 1.8L swapped in or not. Also, i noticed you guys are listing the 5-speed trans as bad and in need of a 6 speed swap? Isn't a 5 speed swap usually the best? For instance many STI/EVO owners, along with those who swap rb25/26 motors always ditch the 6 speed trans for the stronger, longer gears of the 5 speed counterparts.


haha, thanks?

I have broken two 5-speed trans in less than one year. I am putting a 6-speed in now. (it should be finished later tonight.

There are far fewer people breaking 6-speed transmissions. I will have to eventually change my rear-end from the 4.3 to a 3.9 or 3.63 gears. Otherwise first gear with the 4.3 rear end will do something like 10mph at 7500rpm or something rediculously slow.

Find me an STI guy who will straight trade his weak-ass 6-speed for a WRX 5-speed, and tell him I have a bridge to sell him too.

The moral of the story is that you shouldn't take transmission advice from AWD family sedan owners for your RWD sports car.

1.8s will make more power everywhere, all else being equal. It's 240+ccs of additional displacement. To put that in perspective, the difference between a stock 1.8 and the FM 2.0 stroker is less than 160ccs.

On small turbos, the spool difference is negligible. We're talking 2554/2560 sized stuff, it's a couple hundred RPM. Once you get into a 28R frame turbo, like a 2860RS, the differences is very noticeable IMO. The 1.6 car will spool slower, later and harder - it will make less torque down low and be harder to drive.

At the end of the day, in order to reach a reliable, track-duty approved 250whp, you're going to spend 7-8k between the built motor, 6-speed, new diff, good turbo manifold, quality intercooler, the oil cooler, the name-brand clutch, the radiator, and all the other little crap that adds up super fast. The last thing you want to do is skimp out in the beginning and start with an inferior drivetrain because you wanted to save $400 at the beginning of your $8000 build. Do it right the first time, you'll thank me later.

++

sti owners upgrading form 6 speed to 5 speed? HAHAHHAH are you retarded?

Evo owners on the other hand, DO change from the MR 6 speed to the regular 5 speed cause the 5 speeds are just as strong if not stronger and have better rations (though still shitty cuase they're so close)