Im gathering all the turbo stuff now and Im not sure what I am going to do with fuel. I have a DE-K motor in my 98 Max so I have the top feed injectors. From searching, there seems to be an issue with flooding on a cold starts because the injectors being too large. Using the emanage seems to help correct this some but from searching, 550cc seem to be the limit.

My options right now for injectors are RC 550cc, Siemens Deka 570cc-55lb/630cc-60lb and Deatschwerks modified 350z injectors 550cc. I will also be spraying a wet shot of nitrous so I want to keep fuel pressure close to stock as possible.

I just wanted to see how everyone with 500+cc injectors + stock ecu is running and if they have a flooding problem. Any help is greatly appreciated. Thanks!

 

I beleive Mike (I30tMikeD) ran with his stock ECU, 550's, Turbo, and his AFR's and cold start were ok. He was running a SAFC as well and Z32 MAF...His injectors were side feed btw.

-matt

 

I'm running NA with a stock ecu,z32 maf, SAFC @ 0% correction, afpr and 500cc. No problems so far, no hard starts and FP is near stock 1psi less.
Now waiting on the turbo install...

 

if you run the emanage it will pulse your injectors for a proper fuel mixture at stock FP. I am going this same route. DEK fuel rail.

 

The emanage will be able to do it with any size injector? Even up to 630cc will be fine? Also, does it control what happens on startup, from searching, i have read that the ecu will dump too much fuel on initial startup and I dont think the emanage can do anything about that.

 

The Emanage Ultimate will have cold start tuning..Im not to sure about the Blue..I think the blue you cant do anything for start up

-matt

 

if you are using top feed injectors, couldn't you use dsm injectors? They're cheap and you can easily find different sizes.

 

I'm running Nismo 740cc injectors w/e-manage, My cold start is all good but it's kinda hard to start my car when it is warm, but that should all be fixed when i upgrade to the EU.

 

Thats good to hear, I was not aware that the emanage Ultimate had some type of cold start tuning.

Royal_T, is there any adjustments with the e-manage for your 740cc to get the car started? I plan to get an EU for sure but was just curious because some people seemed to have problems with 510cc injectors.

 

I'm running 660 cc's w/ stock ECU and emanage. Z32 MAF, SARD FPR set to 26 psi. Cold start is fine, but you have to wait for the car to warm up before you drive it, or else it will bog a little. In cold start, the emanage can't compensate.

Royal, do you have a push button ignition? I had to install one. On cold start, the car would start fine since the fuel system has dropped pressure from sitting. But if it's warm, the car would not reliably start w/ the key so I installed a push button ignition for those times.

 

I read that Mardi also had a push button start. Shadown, you have the base fuel pressure lower and it still hard to start when the car is warm?

On a cold start when the fuel pressure has dropped, doesnt it go right back up when the key is in the on position?

 

Yes, the car won't start consistently when it's warm without the push button. If I crank it long enough with the key, it will backfire.

And yes, when you put the key in the on position, fuel pressure does go up to base. So I'm not really sure why the car will start better whent he fuel system depressurizes. I only came to that realization after I depressurized the fuel system a few times while working on the car, and the car started right up afterwards even though the car was still warm and wouldn't have started otherwise.

 

I will have to check with SGP to see what they set my settings to but i remember that Mardi tried it with the stock ecu and set the e-manage to 370cc and to scale to 740cc and he said there was no problems starting.


Shadow,
I do not have a push button ignition, but i bet that would solve my ignition problem when my car is warm. SGP told me that once i upgrade to the EU that they could fix that problem with the new system. We will see once they finally come out with the new update for our cars.

 

My car is just the opposite of what the other guys with emanage have described. The colder my car is (and the colder the temperature is) the harder my car is to start. Warm car starts normally.

 

550cc DW injectors, Z32 MAF, stock ECU, 43 base FP. No starting problems ever. The car will bog if I try and get on it when the motor is dead cold. Takes 2 mintues to get past that point, it is really a non issue. I would never boost my car on a cold motor so what does it matter.

 

I30tMikeD, are those DW injectors modified stock injectors or modified 300zx injectors? DW has the modified 350z injectors which would fit perfectly.

Also, what are you using to tune?

 

First off, after getting to see several different companies high flow injectors, I have come to the conclusion that most injectors out there are all a some sort of stock injector modified to flow more.

Wouldn't modified 300zx injectors still be modified stock injectors???

I have red top DW 550cc injectors.

The DW top feed injectors will work fine. We just had a 350z with an APS TT kit put down 470whp with the new DW top peed injectors

I have a JWT ECU, but am currently just using the stock ECU with an SAFC.

 

I would not doubt that many other companies modify stock injectors also.

I was just asking about the 300zx and Maxima A32 injectors because I assume they are not the same size, the 300zx have a larger body (correct me if im wrong) so boring them to 550cc, they would have a better spray pattern then Maxima injectors at 550cc. Yours are working fine but I was wondering which ones you have (red top=A32?), if they are 300zx modified, then my modified A33 top-feeds might not run as good as yours, I might have a starting problem and the spray pattern might not good enough at a low pulse width.

Im going to go with either the DW 550cc or domestic Siemens Deka 630cc. The DW will cost me $375 with a core exchange and the Dekas will be $365 w/ clips. I rather have the 630s because with my goals, the 550s would be close to their limit but it still would be fine.

 

We can do up to 660cc for the top feeds. DW are also the only drop in high flow injector available.

There is no difference between the spray pattern if you were to use a stock A32 or Z32. Spray pattern has never been an issue with DW injectors. Tuners such as Enthelpy and Jim Wolf have flow tested these injectors with no issues with spray pattern.

 

Interesting thread! The bogging and warm start issues are due to warm up enrichments. Your cars are probably tuned for cold start. When warmed up they probably dump a little too much fuel in there. There really needs to be a warm up enrichment table in the emanage or whatever you are using.

I found on stock ECU even with stock injectors, if I stalled the car when cold, it would be almost impossible to start. I don't seem to have that issue anymore!

On the subject of top feed vs. side feed, does anyone happen to know if the DE-K top feed rail will clear the VQ30DE MEVI? I want to run 780cc topfeed injectors I have laying around.

 

I think the EU has some thing for warm start but let me double check

 

Hey Mike where you been,haven't seen you post on here lately.Hey what's the advantage and disadvantage of using the stock ecu compare to the JW?Beside raising the rev limit,advance and retard(emanage blue can do this I believe)timing?

 

i have power enterprise 510cc injectors w/ emanage and have no issues. Only in the morning do i have to let it warm up for a second then it drives like a dream

 

Chris where did you buy those top feed injectors from? the power enterprise?

 

I got them off of ebay, but you can find them on gruppe-s or on my350z.com.

 

Went out of town....then moved....lazy about getting my internet hooked up. Comcast came by today so I am back online.

Are you asking stock ECU alone or stock ECU with the use of a piggy back like e-manage?

 

Well I'm askikng about the main different between the stock ecu and JW,like how are they different,beside like rising rev limit,retart and advance timing.Can you do all that with the piggy back(btw I got emanage blue) except rise rev limit,I know the EU can rise the rev limit and ALL,but after hearing all the trouble you and other member had with the JW,that's why I want to see what's the benefit of using between the two?I don't really care about the rev limit,if I can keep the stock ECU and without the cold start problem and CEL.Sorry for the long post.

 

Actually, the Emange blue can't advance timing nor raise the rev limit, same with the EU at the moment even though its an feature due to the firmware not reading some of the sensors (Crank?) correctly. So to answer that question, no a piggy at the moment will not raise rev limit or advance timing, it will however let you run bigger injectors, tune your A/F and retard timing.
Like a few of the other people on this board, I have not had a problem running DW 500cc injectors on stock ecu. No CEL nor hard starts and its in the 30s every morning right now.

 

Besides the rev limiter and timing changes a reprogramed ECU like a Jim Wolf also controls the injectors properly. But emanage can do that as well. A properly reprogramed ECU is better than a piggy back any day IMO. The key to that statement is properly and the downside to a JWT ECU. To truely get the right tune from a reprogramed ECU there needs to be dynoing and data logging and chips burned and reburned till it is right for your car. That is something you can't get with an off the shelf JWT program. My expierence tells me that the timing is just way, way to conservative and it just kills power. Now, Jim Wolf is willing to make changes but alot of foot work has to be done and chips sent back and forth. With e-manage you could just spend an afternoon at a dyno or sometime on the street with a WB and data logging functions to get a decent tune.

 

I have a set of 612cc deatchwerks I need to sell, they are sitting in the garage in the fuel rail still ready to be shipped out. Someone buy them .