I have a 1991 miata with 33,000miles on it, 5sp, a/c and cruise. I would like do a DIY turbo IC kit to it. I have seen 2 types of exhaust manifolds, cast iron and stainless steel. Is it better to go one way or another? what hp levels can the stock 1.6 take and live? thanks, Scott.

 

cast iron is usually a log style.
stainless steel is usually the tubular style.

Completely different manifolds. Do a basic search on both styles to decide which will fit your goals and budget. One is cheaper and more durable but less power gains and flow, the other is much more expensive and makes more power but has a higher chance of cracking.

Your question is too vague and you have tons of research to do.

 

I know they are completly different but hve not not been able to find any data on them to compare flow rates. I have also found them close in price. Guess you get what you pay for.

 

They are not close in price. A properly built tubular is usually at least 100 more and most are 3-400 more.


Reason you haven't found flow rates is cause no one flow tested them back to back.

Why don't you do it and post flow rate comparisons

 

18 PSI,
ebay item number 400142278785 is a cast iron manifold for 99.99
ebay item number 270624902532 is a tubular stainless manifold for 100.00
I think .01 is close in price. And, my second statement "I guess you get what you pay for" is true.

 

Ohhh boy.

I got a laugh out of that.

 

I think the answer you are looking for is that they are both crap. And the 1.6 can handle anywhere from 150 to 250hp reliably, depending on how horrible/good your build is. Many people have destroyed their motors at low boost. This forum is filled with all the information you need. Do some research.

 

Oh wow. You have gone from n00b to FAIL.

Disregard my previous statements. I'm not even going to waste my time.

I suggest a whole lot of reading the stickies and searching before you post more fail threads or a thorough flaming is in your future.

And no I'm not being mean. I'm actually helping you fail less.

 

If you are paying less than $400 for a manifold, you might as well buy two, so when the first one goes bad, you have a second to put in its place while you save $400 for a third.

 

Unless it's a used quality piece. You can pick up used Begi and flyin miata manifolds every once in a while for a good price. I got my previous HKS manifold for $100 mark used and it was a great product. Just keep your eyes open.

 

thanks for the info. I tried to search on the forms for the comparison I had asked about before posting and nothing came up. I have read the discussion "Underdog's de-Greddified Sunburst Yellow" where he used the cast manifold I was talking about and seemed to be happy with it and nobody had said anything about it being junk, so I thought it was an ok part. I have about 10 hours of reading different posts to see what you guys are having success with and what to stay away from. I think I will just buy a complete kit from BEGI or someone else with proven success, Thanks again for your input.

 

Don't get distracted from DIY, just make sure you know what you are getting in to. I bought the Flyin miata DIY kit (manifold and downpipe) and did everything else custom. It works great and I saved money.

 

really guy? just keep saving ur cash and dont waste ur money on either one. and as far as comparrison steel to iron, is ur car a daily or track car?

 

ahhh... newb on newb love.

 

its just a daily driver I have had for about 8 years. I am not looking to change the rotation of the earth, just wanted to get what power I could without getting into the motor for major upgrades. I drag raced inline 4 cyl motorcycles from 82-04, running carb turbo gas, carb turbo NOS, and my last 6 years were on a turbo inj alcohol @ 52 lbs boost. Thought I could pick up what you car guys run and build it my self, part of the fun is building it. I know what works in bikes, the weak points, on my Miata, I don't, just what i read.

 

Just to keep some informative information in this thread, if you have to buy an ebay manifold... make sure it's a cast unit like this:





Anything available on ebay but for the one above, or an actual name brand manifold will fail.


Never purchase the one below:

 

And that's why they're trying to tell you to get a good manifold. The ones you listed are junk.

 

and to add to that, it being a daily, in my experience (w/ several dif makes of turbo cars honda, dsm, blah) cast iron has always upheld far better than stainless and i have tried both. daily?= cast iron

 

I hear you, sold my boat and have the cash to go forward with something, looking at complete kits from the big guys, or doing my own thing, still reading up on everything, mostly ECU's now. I will for sure follow Braineack's post if I do my own thing. Have pages of notes here to compare. from what i understand to run low boost say up to 6psi, I would need some type of fuel pressure regulator. To run say 7psi or more add to that some type of ignition retard, and more boost than that I may as well get a different ECU, possibly a mega squirt, and larger injectors/fuel pump, and inter cool it.

 

Or you could go to Meet and Greet section and post an intro thread with all your information. Like what year miata you have, experience with cars, and where you are located at.

After that you will learn that while an AFPR will work it is less the ideal and you should probably just use the money to go straight with an after market ECU.