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karlou426hemi 10-16-2014 02:08 PM

damn it is posted earlier in the thread. 20-22 deg of timing and around 12psi of boost.....

18psi 10-16-2014 02:09 PM


Originally Posted by karlou426hemi (Post 1176038)
damn it is posted earlier in the thread. 20-22 deg of timing and around 12psi of boost.....

I guess I missed it. my bad.

now I'm really confused, because I bent all 4 rods on my '00 with less timing and same boost, and really conservative afr's.

and that was a 9.5:1 engine

Leafy 10-16-2014 02:11 PM


Originally Posted by 18psi (Post 1176039)
I guess I missed it. my bad.

now I'm really confused, because I bent all 4 rods on my '00 with less timing and same boost, and really conservative afr's.

and that was a 9.5:1 engine

he's using an FIC, so thats stock timing - 20-22 degrees.

karlou426hemi 10-16-2014 02:14 PM

no stock timing minus 5-7

karlou426hemi 10-16-2014 02:21 PM

18psi its preatty simple. you probably have a less flowing exhaust. less flowing manifold. less flowing turbine. and a smaller intercooler. thats why you can detonate and engine running less timing and richer afrs.

do a quick search. when mazda introduced their new turbo skyactive engine from japan to america they had to drop compresion by a whole point ( went from 14 to 13:1 ). and the only reason for that is because they had to shorten the manifold tubes for emmission purposes. that how important manifold flow is.

another example i can give is on my old engine on my supra. with a bolt on turbo at 20psi on the stock cast manifold i was running 7deg of timing anything more and i would hear it ping. than with the same tubo and downpipe i did a custom turbo header and at the same boost i was now able to run 16 deg of timing.

18psi 10-16-2014 02:31 PM


Originally Posted by karlou426hemi (Post 1176048)
18psi its preatty simple. you probably have a less flowing exhaust. less flowing manifold. less flowing turbine. and a smaller intercooler. thats why you can detonate and engine running less timing and richer afrs.

do a quick search. when mazda introduced their new turbo skyactive engine from japan to america they had to drop compresion by a whole point ( went from 14 to 13:1 ). and the only reason for that is because they had to shorten the manifold tubes for emmission purposes. that how important manifold flow is.

another example i can give is on my old engine on my supra. with a bolt on turbo at 20psi on the stock cast manifold i was running 7deg of timing anything more and i would hear it ping. than with the same tubo and downpipe i did a custom turbo header and at the same boost i was now able to run 16 deg of timing.

The problem is:
I had a tubular manifold
I had a 3" exhaust
I had a gt2860rs .86
...anddd I was running a whole .5 less static compression.
the only variable here that I could think of is you have much better gas vs my CA 91oct piss. but my car never detonated or knocked that I remember, so...

It's cool, I realize its pointless to compare, I'm just really surprised.

karlou426hemi 10-16-2014 03:12 PM

well im also surprized. maybe fuel is of poor quality in your area. but what matters when you ben a rod is the trq you have no matter what parameters give that trq.

how much trq did you had when you bent the rods
at what temperature you dynoed the car

its nearly impossible to have my numbers at my boost level since in california temperature is a lot warmer. mine was dynoed at about 40deg F

karlou426hemi 10-16-2014 03:17 PM

most of time people break engines because they dyno at the limit of stock internals on a hot day and then do a pull on a cold night so boost is up by 1-2 psi and air is more dense so you en up with 270wtq instead of the 240 on the dyno so the engine pop or bend a rod

karlou426hemi 10-16-2014 03:20 PM

for exemple. a guy that was at our supra dynoday this summer put down 518 whp at 22 psi and this same car dynoed at the same wastegate dutycyle 615whp at 24 psi in the winter when it was built. we are talking here of dyno temp of 110 degf on the summer pull and 35 deg f on the original winter tune

Leafy 10-16-2014 03:20 PM


Originally Posted by karlou426hemi (Post 1176080)
most of time people break engines because they dyno at the limit of stock internals on a hot day and then do a pull on a cold night so boost is up by 1-2 psi and air is more dense so you en up with 270wtq instead of the 240 on the dyno so the engine pop or bend a rod

Sure, but you dyno'ed over the limit of the stock engine, while on imprecise engine management.

karlou426hemi 10-16-2014 03:21 PM

the limit is 250wtq.
this is a semi safe limit.
im at 256 so not a lot over
and in the summer with hot temp we are probably at around 230-240

karlou426hemi 10-16-2014 03:27 PM

plus an fic is not imprecise at all when tuned correctly.
a megasquirt is not better when not all tables a tuned correctly

when you get your ms tuned on a dyno the tuner ajust the fuel table and ignition table and thats it ( well every tuning shop i saw in my life do that ). there a lot more than these 2 tables to tune if you want it to be reliable. and im sure a lot of user run the ms with all these tables tuned like crap witch transform to good tune on the dyno in a crappy tune on another day.

Leafy 10-16-2014 03:41 PM

The stock engine limit is from peak cylinder pressure. Which is why you can nuke a rod below the "safe" limit with knock. And why 18psi assumed you were making your unusually high power by running high boost and low spark advance, since that creates lower peak cylinder pressures and a wider pressure curve than running lower pressure with more advance. Its gentler on the rods while being harder on everything the hot combustion gases touch because they're hotter in that setup.

And lets face it the FIC IS less precise. You have no ECT or IAT input to the unit. You're fully at the mercy of what the stock ecu does with these values and have to tune around it. You're dealing with tuning around a pre turbo IAT value on top of that. And we can see from your dyno a few pages back how imprecise it is in your AFRs, they drop below what the wideband can read during spool up but peak at nearly 13 at peak torque because, "I had to have that rich part because there is no load enrichment in the stock ECU with the AEM FIC and if it is not there it would go crazy lean when boost would build fast when shifting or flooring it at high RPM." And thats on the dyno when it was tuned, who knows what its doing in varied engine coolant and intake temp situations.

karlou426hemi 10-16-2014 04:04 PM

iat is before the tb not before turbo

and yes i said ms is more precise. but most tunes in the ms aren't thats what i mean

Mazdaspeeder 10-17-2014 09:41 AM

This is impressive, but you know it's just a countdown to the inevitable. There are more stock components than rods you should be worried about, such as your oil pump, or piston rings. Wish you luck with it

karlou426hemi 11-27-2014 11:47 PM

A friend showed me my old video of my protege I made so i tought some of you would be interested in seeing it.
This was the year before we putted slicks on the car so it is on street summer tires
Still it pulls great for only 19psi. A good comparison of how it pulled is the s2000 on the third race as soon as i have some traction :)


NBoost 12-02-2014 09:57 AM


Originally Posted by 18psi (Post 1176049)
The problem is:
I had a tubular manifold
I had a 3" exhaust
I had a gt2860rs .86
...anddd I was running a whole .5 less static compression.
the only variable here that I could think of is you have much better gas vs my CA 91oct piss. but my car never detonated or knocked that I remember, so...

It's cool, I realize its pointless to compare, I'm just really surprised.

Dude.. You have done nothing but troll this thread since 2013, have posted 0 useful advice, and continue to down-talk this guy's perfectly successful turbo build (and damn good fabrication work while we are on the subject). Seriously, what the FUCK gives? I read the whole thing from front to back, and if I read another butt-hurt reply by you because you figured out you can't tune a car as well as many other people in the Miata world, I am going to puke. Forums like this need much more PRO-ductive people, and supportive people. Its a community, not a flame fest.

Do you realize posts like yours over the past 1.5 years in this thread, equate to nothing useful? Think about that for awhile.

Back on topic..

To the OP, I am thoroughly impressed by the kit you built and the numbers it made. I am also someone who realizes reliability is all in the tune, and you have proved that 120%. Its shocking some "tuners" still haven't figured that whole idea out.

I sure wish I had the cash for that kit, its well built without a doubt.

18psi 12-02-2014 10:00 AM

Silly n00b.
Get lost before I make you cry.

NBoost 12-02-2014 10:07 AM

Irrelevant. Relevant questions at hand:

1) How many "failed" builds happened in this thread? 0.
2) How many helpful, and proactive posts have you made in this thread? 0.

If you are going to argue your advice as "useful", in this thread, then you truly are an idiot and have no hope. By the way, "useful" advice isn't "This has been done before, failed, so you are an idiot for trying".

You will grow up when you stop equating someone's knowledge to how long they have been a member, or even active, on a forum.

My point was, make the forum a PRO-active place, not post pointless troll posts that the OP will likely ignore anyway.

18psi 12-02-2014 10:20 AM

:laugh: How many miata's have you built? How many have you tuned? How many threads or posts do you have on here helping people?

Silly self entitled drama queen metro pissant, you don't get to call the shots here with your emo drivel. You haven't been "broken in yet", the attitude is simply adorable.

Crying and demanding to be spoonfed while criticizing the people that have the information is a failed approach. You'll have to change your tampon and unwad the panties for round 2.


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