New guy post.... How reliable are turbo miatas?
#22
Long post... I was on a roll.
Cryo... welcome to mt.net... I noticed you've been a member here for awhile but never posted... place your location in your profile and place your Supra plus short mod list in your profile. Do not anchor on Zabac's post in your initial reply in this thread. We have a NOOB hazing ritual and you are prime fodder by being a Supra owner. The mods around here run a tight ship, don't tolerate bullshit, and wield the most often used bansticks on the internet.
You'll find the answers to all your questions are met with immediate and good to-the-point information as long as it's very obvious you did some research yourself before asking the question. As Zabac said, we do not spoon-feed. Forums that spoon-feed end up with an endless amount of THE EXACT SAME TYPES OF THREADS that are impossible to get reliable and consistent information out of for the NOOB who shows up and actually knows what the search button is.
Hints for all NOOBs:
Put location in profile.
Put short list of mods in signature.
Visit all companies websites in the Vendors Forum and be familiar with everything they sell.
Use the SEARCH button liberally (title searches limited to appropriate forums are best).
GOOGLE has been proved since it's creation to the best source of information about anything on the internet. If you type in any question relating to turbo Miata's into GOOGLE, quite a few hits will be links to threads in this forum.
Always visit th USEFUL SAVED POSTS forum before asking questions.
READ THE FAQ.
A PIC/VIDEO/SOUNDCLIP IS WORTH A THOUSAND WORDS AND WILL ALWAYS GET YOU BETTER HELP THAN ANY AMOUNT OF DESCRIBING THE PROBLEM.
Other things that will help you on all forums everywhere:
Have a digital camera with video-capture capability.
Have a Photobucket account.
Have a Youtube account.
Have Microsoft Image Resizer Powertoy installed (or another super-easy resizing program for creating forum-friendly quick-uploading pics).
NOW, I will spoon-feed you this one time, but never again:
1) Rear-end.
90-93 cars come stock with a 6" ring gear and 4.30gears. People have broken the dif on stock (100whp) power. It can however last a long time at 200whp+ with good fluid, no drag's/drizfiting/burnouts/etc... A good guess is that if you're gentle, it's probably good to about 250whp accelerating in a straight line and waiting for WOT until the clutch is fully out. Above that, you're gonna break it doing anything short of a 5th gear gentle roll-in. The majority of 90-93 dif's were open. There was a VLSD (viscous) option and most of those difs lasted about 50k before they were no longer effective at limiting slip.
94+cars all have 7"difs. They are good for over 300whp with moderate to extensive abuse. 4.30/4.10/3.90(6-spds) are the 3 factory gear options. Many cars came with a Torsen LSD depending on trim/options. Currenlty, you can get a 3.636 or 3.308 rear-gear that is the mod of choice for 300whp cars... makes 1st gear useable again. You can take any 90-93 car and install the driveshaft/dif/carrier/axles from any 94+ car... direct plug-in.
2)Engine management
The quickest/easiest/cheapest way to get your Miata boosted is to use a RRFPR (rising rate fuel pressure regulator) to increase fuel-rail pressure when in boost. 5-6psi boost and 70-80psi(limit of stock fuel pump) pressure in the fuel rail, in conjunction with 6* base timing can be done non-intercooled forever. The 90-93 Miata Greddy turbo kit (sold by the thousands) gets you 145-150whp in exactly this manner. Base stock timing is 10* BTDC so you're hurting your low-rpm performance out of boost... and it's a little laggy due to the small DP, but it's easy and proven. The current ****-hot non-intercooled AFPR (adjustable fuel pressure regulator) system on the market is the BEGi"S" system... leaps and bounds better than the Greddy and easily upgradable.
^These systems we call "bandaid" systems as there's no EEM. You can add an electronic timing retard box (Bipes), 02clamp, slightly bigger injectors, fuel pump, intercooler for the ULTIMATE bandaid setup and run about 12-14psi... maybe 220whp before the limits of the stock ECU catch up to you. This is how a lot of people get started into boosting Miatas. It's cheap, parts are plentiful used, and the corporate knowledge will not let you make mistakes.
The most popular aftermarket ECU choices are as follows:
Megasquirt (currently available PnP 90-97 and lots of guys running 99+ cars with MS in parallel to stock ECU)
Hydra ($2k, it's the best you can get PnP).
Xede (extremely capable piggyback, great choice for 99+).
Emanage (regular/blue/Ultimate... +Boomslang FTW)
Link (90-93 need so find used, 94-97 still for sale, for a long time it was the only PnP choice)
ZOOM3 (will be released any day now, might be the **** for 99+guys depending on how big an injector it will idle)
Less popular/capable but still used in decent numbers: AEM/SAFC/Voodoo/other similar piggys all doing the same thing.
You'll find the answers to all your questions are met with immediate and good to-the-point information as long as it's very obvious you did some research yourself before asking the question. As Zabac said, we do not spoon-feed. Forums that spoon-feed end up with an endless amount of THE EXACT SAME TYPES OF THREADS that are impossible to get reliable and consistent information out of for the NOOB who shows up and actually knows what the search button is.
Hints for all NOOBs:
Put location in profile.
Put short list of mods in signature.
Visit all companies websites in the Vendors Forum and be familiar with everything they sell.
Use the SEARCH button liberally (title searches limited to appropriate forums are best).
GOOGLE has been proved since it's creation to the best source of information about anything on the internet. If you type in any question relating to turbo Miata's into GOOGLE, quite a few hits will be links to threads in this forum.
Always visit th USEFUL SAVED POSTS forum before asking questions.
READ THE FAQ.
A PIC/VIDEO/SOUNDCLIP IS WORTH A THOUSAND WORDS AND WILL ALWAYS GET YOU BETTER HELP THAN ANY AMOUNT OF DESCRIBING THE PROBLEM.
Other things that will help you on all forums everywhere:
Have a digital camera with video-capture capability.
Have a Photobucket account.
Have a Youtube account.
Have Microsoft Image Resizer Powertoy installed (or another super-easy resizing program for creating forum-friendly quick-uploading pics).
NOW, I will spoon-feed you this one time, but never again:
1) Rear-end.
90-93 cars come stock with a 6" ring gear and 4.30gears. People have broken the dif on stock (100whp) power. It can however last a long time at 200whp+ with good fluid, no drag's/drizfiting/burnouts/etc... A good guess is that if you're gentle, it's probably good to about 250whp accelerating in a straight line and waiting for WOT until the clutch is fully out. Above that, you're gonna break it doing anything short of a 5th gear gentle roll-in. The majority of 90-93 dif's were open. There was a VLSD (viscous) option and most of those difs lasted about 50k before they were no longer effective at limiting slip.
94+cars all have 7"difs. They are good for over 300whp with moderate to extensive abuse. 4.30/4.10/3.90(6-spds) are the 3 factory gear options. Many cars came with a Torsen LSD depending on trim/options. Currenlty, you can get a 3.636 or 3.308 rear-gear that is the mod of choice for 300whp cars... makes 1st gear useable again. You can take any 90-93 car and install the driveshaft/dif/carrier/axles from any 94+ car... direct plug-in.
2)Engine management
The quickest/easiest/cheapest way to get your Miata boosted is to use a RRFPR (rising rate fuel pressure regulator) to increase fuel-rail pressure when in boost. 5-6psi boost and 70-80psi(limit of stock fuel pump) pressure in the fuel rail, in conjunction with 6* base timing can be done non-intercooled forever. The 90-93 Miata Greddy turbo kit (sold by the thousands) gets you 145-150whp in exactly this manner. Base stock timing is 10* BTDC so you're hurting your low-rpm performance out of boost... and it's a little laggy due to the small DP, but it's easy and proven. The current ****-hot non-intercooled AFPR (adjustable fuel pressure regulator) system on the market is the BEGi"S" system... leaps and bounds better than the Greddy and easily upgradable.
^These systems we call "bandaid" systems as there's no EEM. You can add an electronic timing retard box (Bipes), 02clamp, slightly bigger injectors, fuel pump, intercooler for the ULTIMATE bandaid setup and run about 12-14psi... maybe 220whp before the limits of the stock ECU catch up to you. This is how a lot of people get started into boosting Miatas. It's cheap, parts are plentiful used, and the corporate knowledge will not let you make mistakes.
The most popular aftermarket ECU choices are as follows:
Megasquirt (currently available PnP 90-97 and lots of guys running 99+ cars with MS in parallel to stock ECU)
Hydra ($2k, it's the best you can get PnP).
Xede (extremely capable piggyback, great choice for 99+).
Emanage (regular/blue/Ultimate... +Boomslang FTW)
Link (90-93 need so find used, 94-97 still for sale, for a long time it was the only PnP choice)
ZOOM3 (will be released any day now, might be the **** for 99+guys depending on how big an injector it will idle)
Less popular/capable but still used in decent numbers: AEM/SAFC/Voodoo/other similar piggys all doing the same thing.
#35
Elite Member
iTrader: (11)
Join Date: Jun 2007
Location: Overland Park, Kansas
Posts: 5,360
Total Cats: 43
1. Belt Slippage
2. Boost adjust ability
3. COST
Did I mention Belt slippage?? I'm not even attempting to start this debate, but its been proven more than once an MP45 @ 8psi made less peak power and torque than a properly sized turbocharger @ 8psi...
Friend has an MP45 on his miata. In the stock 5psi form it made 147rwhp. After a 250$ high flow cat, longtube header, exhaust, 8psi pulley, more timing and more fuel.. it made 158rwhp. That was over 700$ in upgrades to get that extra 2psi along with supporting mods and it didn't do dick.
#37
Well, im putting down far more power than a torqueless RX8 and have no problems..... and that's WITH hard driving. Though, I blew up two 5-spd Miata transmissions... which have a lot in common with NA FC RX-7 transmissions...which were HORRIBLY WEAK.
But back to the original question... i don't think the NB 6 spd has nothing in common with the RX8
#38
I am not gonna even attempt to answer that, you should know better than to ask such a noob question...
You should know that your budget will determine how reliable any build is.
Bone stock, you cannot kill a Miata unless you neglect critical maintnance, with boost come problems, how many and how big depends on how much boost and all other supporting mods.
Make a proper introduction in a proper forum and your stay here will be much more welcomed. We don't spoonfeed people here.
Now, Pics or BAN!!!
You cannot storm in here talking about turbo supras and not give us any pictures...or vids. If you have neither, nude wifes or girlfriends will do.
You should know that your budget will determine how reliable any build is.
Bone stock, you cannot kill a Miata unless you neglect critical maintnance, with boost come problems, how many and how big depends on how much boost and all other supporting mods.
Make a proper introduction in a proper forum and your stay here will be much more welcomed. We don't spoonfeed people here.
Now, Pics or BAN!!!
You cannot storm in here talking about turbo supras and not give us any pictures...or vids. If you have neither, nude wifes or girlfriends will do.
I am very aware of old car maintenance, and that is always the 1st thing i do when i get a car. Replace most hoses and gaskets. A modded POS engine won't hold up or keep up to a properly running one.
I don't know if anyone appreciates the older supras but here is mine.
DSC_2163.jpg?t=1216698718
Since you already have experience with turbo vehicles, I'll go ahead and assume you understand that as your goals (and boost pressure) become more lofty the need for sturdier hardware and more comprehensive engine management increases.
The block is good for around 15 psi (debatable and there are other factors, of course) on the factory internals, the rear in the 1.6 cars blows fairly easily even at low-boost and in some cases at stock power, but it is easy enough to swap to the later rear from a 1.8 car (6" gear versus 7"). Transmissions are also a known weak point.
Fewer and fewer people around here rely on something other than a replacement ECU for engine management, or at least it seems that way. Most NA owners use a Megasquirt and many NB owners use a Hydra EMS.
The block is good for around 15 psi (debatable and there are other factors, of course) on the factory internals, the rear in the 1.6 cars blows fairly easily even at low-boost and in some cases at stock power, but it is easy enough to swap to the later rear from a 1.8 car (6" gear versus 7"). Transmissions are also a known weak point.
Fewer and fewer people around here rely on something other than a replacement ECU for engine management, or at least it seems that way. Most NA owners use a Megasquirt and many NB owners use a Hydra EMS.
Wow. 1jz Miata, i like! haha. Oh and there was no 1jz in 6 speed, only the mark 4 2jz.
Thanks for everyones post's so far, it is helping me inquire more about these cool little cars