Ok guys, I need to bounce some ideas off you with some experience with the Greddy turbo kit on a 1.6L..

background...I am very familiar with NA miata and own a 90 that I Auto-x. I also own a dyno shop and am VERY familiar with just about every method to fuel a turbo motor from stand alones, piggy backs, rising rate, aux injectors etc etc

so..... a customer brings me a turbo miata at my shop to figure out why it won't run well......I have very little history on the progression of the install but I will tell you all I know..


below is the setup it came in with:
1990 1.6L with Greddy kit including the rising rate regulator
MSD 8662 timing control
adjustable fuel pressure regulator set about 40psi
early 5 **** SAFC(***** in very strange posittions)
330 injectors

my thoughts are to return it to its basic setup as Greddy envisioned

so I replaced the stock injectors
and set the ***** to zero

it still runs horrible.

also I checked max ouput on the pump and it will only make 65 psi max(checked by pinching off return line). also what is the desired fuel pressure rise for the stock Greddy setup? 7psi per lb of boost? at 5psi boost this pump will not make enough fuel pressure....is this likely a weak stock pump? what is the required fuel pressure for a stock Greddy turbo kit...


so is the SAFC causing problems? the instruction manual does not have any setup for the 90-93 miatas so the previous mechanic set all of the dip switches for a 1995..

should I remove the SAFC? I keep reading conflicting information regarding the usage of the SAFC, but I am seeing a lot of info stating they will not work. will it ever work without trying to "fool it"?


any guidance on this setup would be appreciated...my goal is to return to a basic Greddy setup...Megasquirt, emanage etc are not an option. Thanks for all of your experience and feedback...


Peace........BartG


www.teamgodspeed.com

 

it really doesn't need the safc, and doesn't really work very great on our application.

the car should idle at 35psi, and see 50psi at 0~hg. The pump output seems low, it should be reaching 75-80psi. Make sure it can even maintain 65psi on the road.


The GReddy kit runs at 5psi from the factory with the 203cc injectors. the FMU is a 12:1 disc, and typically runs a tad bit rich.

to idle to 330cc injectors there was probably some fandangling with the AFM. Verify it hasn't been modded. There is a black plastic cover, it should be sealed, if there is evidence that it had been opened and resealed, chances are the spring tension is altered. there is also a little tiny clyinder that sticks up, if there is an exposed screw the idle mixture screw could have been turned.

talk to magnamx-5 as i believe he still runs a SAFC.

 

it didn't idle....AFM was factory sealed....

my guess is it won't do 65 on the road/dyno. once I clamped the return line it took about 3-4 seconds to reach 65psi

thanks for the input....you are supporting my thoughts...this customer has spent WAAAY too much money having people bolt stuff onto this motor and he just wants it to run.

fuel pump replacement...stock good enough?


Peace..........BartG

 

Yeah when you clamp down it shoudl instantly shoot to 65psi. Also check the OEM FPR. Remove the vacuum line to it at idle and watch the fuel pressure. Also check for fuel in the vacuum line if failed.

For the price and application, the walbro 190HP (F20000141) would be better suited. However since the output could reach 120psi, the 12:1 disc in the Vortech should be reconsidered.

 

it has an aftermarket(aeromotive) regulator. it is functioning as designed.

the 12:1 disk should be reconsidered and replaced with?????


Thanks...


Peace.........BartG

 

Bart safc works but not with overly large injectors like in other apps. I would put in a walboro 190hp for your customer at 100 bucks shipped from lightning motorsports it is a easy and effective mod + i doubt that the stock pump is as cheap either. To idle the 300's with out the safc then adjust the clock spring to pretension it as per the solo miata site http://members.aol.com/solomiata/airflowmtr.html Or upgrade to a larger RX7 afm as listed both are identical except for the size. How much timming is your client puling and what is there base timming? A few more answers and we will have him right as rain.

 

based on your boost numbers i would say a 6-1 with the 300's or a 8-1 with the stock injectors. also if a new safc is in order i will have my safc 2 comming up for sale shortly for cheap as i will be going MS. If you are still in the market i will give your customer dibs for 100$ shipped. I just have to install and tune the MS first it gets here tuesday so it shouldnt be to long. from then, it is in excelent condition, and works perfectly.

 

Stupid suggestion... Has anyone replaced the fuel filter lately? Wouldn't it be a good idea to ensure that the stock fuel system is operating under normal parameters first.

 

probably not a bad idea at all.

GodSpeed, you gotta guess that the GReddy at 5psi will produce about 140rwhp, or 160-165BHP or so. With that said, in order to support that much power on 203cc injectors you'll need only about 90-95psi of fuel in the rail.

Since the walbro can produce enough flow at around 100-110psi, the 12:1 disc will throw it to about 110psi of fuel at 5psi of boost (12 x 5 + 50)

so using the 8:1(90psi) or 10:1(100psi) disc would be more idea.


Idling the 330s could be done without the SAFC, however, he's have to deal with cold start mode(too much fuel at idle), adjust the AFM(wideband tuning), and need another disc (4:1). If the car isn't at the point to run over 180rwhp or so, there really isnt a need for those injectors at this point.

 

+1 on the fuel filter i cant believe i forgot that.

 

very good black and tan......sorry guys but I was testing you!....I was wondering who would come up with that... great job...

I believe the fuel filter could cause the slow rise of pressure but will not affect the total rise of pressure....and yes it will be replaced with the pump...

I need to put in an order with mazda motorsports and I can get a stock one for $76 so I was hoping it would work...just makes life easier for me

I need to keep this as simple as possible....if this was my miata I would probably take a different route but with customers I need to look for the simple effective route....if not it gets to expensive for them or I have to give my time away...also this customer towed his car two hours for me to work on it, which means I won't be able to do any tuning in the future..therefore it needs to ship in perfect shape.....so I am leaning towards taking it back to stock and install the Greddy kit as designed...

discs....why did Greddy ship with a 12:1 when a 8:1 is a better choice? is switching to an 8:1 common? do I need to buy the disks drectly from Vortech?...OR since I may run a stock pump does it limit the amount of fuel delivered due to its max possible pressure?

Thanks again for all of the help...it is good to find a site with helpful knowledgable members....



Peace.....................BartG

 

Gredsy did it for carb reasons and to make there product safer running overly rich while killing power makes the motor less likely to ping. + the stock pump is rather limited on its pressure range with 80 or so psi potential, where as the 190 is capable of 100+ psi. both are just as easy to install and require no extra effort or tunning. Like i asked before what does the spark map look like? Stock is not always better there are a load of stock greddy people out there that hate it compared to the alternatives we gave you. Also stock is timming set ast 6 btdc and no FMIC at 6psi. Not the most ideal i think, or what your customer probably was expecting either,

 

Yeah, the stock pump can only flow about around 75-80psi, with the 12:1 disc, your reaching the max output, but it's just enough fuel for the injectors to support the extra HP.

Since the kit is FMU based, going with the HP model Walbro ($93 shipped) makes sense, since it can flow more fuel at higher psi levels, allowing you to support more BHP with the smaller injectors. Otherwise, you'll still only be able to achieve 75-80psi out of a 155lph or 190lph pump and need to increase the injectors when increasing boost.

 

timing issues....sorry I forgot to mention....I do not know! can't keep it running long enough to check it...it does have the MSD retard box but I am going to need to rewire it.
I am going to set it at 14btdc and let the MSD box do its job..

I am currently searching the mazda parts list trying to find the part number of the CAS connector..

I am going to completely remove the SAFC as I believe the "quality" wiring job may be one of the problems..

OK you convinced me.. .I will get the 190lph from lightning...now where to get the8:1 disc...??

this customer is almost in tears.....the last shop charged him $2600 and gave him a car that does not work....he is even contemplating removing the turbo and going back to NA...he just wants to enjoy the car, doesn't really care how much HP it makes..

Thanks again..

Peace.....................BartG

 

does that Walbro kit come with everything I need? O rings? sock filters? etc etc..

 

sounds like that should work. With that 5-7 emjoyable Psi should be real easy to set up. It should you will need to cut the stock pickup and run it with hose and clamps supplied instead of the bell adapter of the 1.6 variety but other than that it is and will perform the same/better.

 

yeah, buy the 94-97 190hp with installation kit.

its extremely simple to install, takes about 30mins.

you'll have to cut the nozzle off the stock rail connector, and replace it with the provided fuel line.

as seen here:


the FMU discs can be purchased at summit racing. It's more cost effective to buy the package: $50 for a 4:1, 6:1, 7:1, 8:1, 10:1 and 12:1 vs. $33 for just one disc.

http://store.summitracing.com/egnsea...s=false&N=+115

that way you can leave your customer with upgradability for the future if he ever plans on it.

 

order pump from lightning...Check
order FMU discs from summit...check
order fuel filter....................check

awesome guidance guys....I will let you know how it all turns out..


Peace........BartG

PS: if you are every in the neighborhood stop by www.teamgodspeed.com

 

Well... I did stay at a Holiday Inn Express last night.

 

OK...I worked late at the shop last night and got all the recommended components installed everything went smooth as silk.....I fired it up and it STILL ran like crap...horrible at idle and off idle sounded like a really bad misfire...I am totally bummed...I have no idea which way to turn...the car has been hacked by so many people...

then I was thinking.....the owner told me he had the head off recently to change a piston....I am thinking.....hhhmmmm I onder if he got the timing belt on correctly? I start checking....the intake cam is off about 5 teeth and the exhaust cam is off about 4 teeth.....YIKES!!!!! I pull the belt and reset and VOILA!!!! the car purrs like a kitten......Woo hoo!!!!! I put on the dyno and made a pull.. 145 HP at the wheels but a bit lean...not enough to hurt it but definitely has a negative affect on output...

so my question is....I have the vortech recalibration kit....how are the discs rated? the smaller the less fuel pressure increase? in this thread someone said I need the 8:1 disc..which one is this? is my goal 85 psi? I had 71 psi at full boost...

thanks again for all the help....

Peace................BartG

also...timing, I have the MSD boost retard...I set my timing at 12 per service manual instructions....this should take me to 6 degrees at full boost...is this the goal...??