When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Although I want one, with my FF960's at 60PSI I drop rail pressure like crazy. Probably why my deadtimes are such a bear to program, I have negative deadtime the longer the injectors stay open...
I like what they did with the countersink for the rail spacers, that's much better than the big ol' pocket on the M-Tuned
Originally Posted by deezums
Although I want one, with my FF960's at 60PSI I drop rail pressure like crazy. Probably why my deadtimes are such a bear to program, I have negative deadtime the longer the injectors stay open...
Weirdness like this is why I went to an NA8 style full return system with a boost/vac referenced Fuelab regulator under the hood when the turbo went on the NB. Such stable. Much Fuel. Wow.
I've converted to return, with a spare feed line as my return instead of the evap line. I've got a DW300 and turbosmart FPR. All in, I should have enough for 400+ on e85 with a wide margin.
No idea why I have such problems. Even just testing one individual injector on a flowbench and I see the pressure drop. The flowbench doesn't give me but 3/6/12ms pulse choices. I've got something rigged up to let me test whatever pulsewidth I want. Might try using haltech to compensate deadtime off the entire pulsewidth and battery voltage both.
I don't think any of the injector dimensions are a factor here. Also, you'll probably want to measure that injector from the sealing shoulder to the top, don't include the lower seal or the tip.
*pictures of measurements*
This measurement isn't accurate with this tool as you are forced to tilt the injector over to get it on the caliper jaw. A better way to do it would be with a height gauge on a surface plate, but I have neither, and this is probably close enough for the sake of argument.
The radius on the ID adapter however...
It fully bottoms out in both my M-Tuned rail and the stock rail. The problem is I DON'T KNOW IF THIS ACTUALLY MATTERS.
You would want to check the distance between the rail spacer where it contacts the head and the sealing "shoulder" on the injector, but again, same applies as above about the surface plate and height gauge. I simply don't have the tools to properly measure this distance.
Forgot the stock injectors had a top cushion since I haven't touched any in ages. The ID1000's contact the radium rail at the top of the injectors before the tophat radius, so I was just assuming it was similar on the stock injectors. Contacting at the radius seems correct though considering it stabilizes the injector and is what contacts with the OEM rail. Looks like my injectors aren't special though... Same measurements on mine.
Not sure how this hasn't seemed to come up before but looks like at least part of the issue is the top of the rail's "injector seat" is offset further towards the head than the OEM rail and the ID1000's have a longer "radius/top cushion" to "top of injector" distance than OEM? (ID = 13mm)
Originally Posted by EO2K
@Jumpster74 When installed per Radium's instructions, does your rail bolt down square without the injectors?
After my last statement, I'd like to point out that it appears OP is not using a Miata valve cover.
Correct, protege cover in use. I've gotta get around to making a build thread on here...
Making sure the rail cleared was the first thing I checked but installed it with no injectors to verify and it clears fine. Radium definitely fixed the issues with the M-Tuned.
Originally Posted by deezums
Looks like you'd need additional rail spacers about the width of the lower injector cushion, at least according to E02K's pic there.
The actual measurement you want is cushion to cushion on the stock injectors, and then cushion to radius on the top adapters. If they aren't the same it's not going to work.
All assuming you aren't crashing the rail ears into the valve cover. Seems Radium has fixed the oversight of Mtuned, the ears come pre-notched.
Mentioned it above but this is what im thinking now too. Radius to bottom of cushion measurement is 60mm on mine and I imagine on EO2K's as well. 13mm from radius to top.
Taking guesses here but sounds like the OEM rail + injector left some space above the injector. ID filled it in with the tophat and radium filled it in by offsetting the seat.
If so, the best solution would be shorter tophats, but at this point, I think I might just take the loss, sell these, and pick up ID1050x's which appear to fit with no issues due to a different, shorter, tophat (need to verify with ID but visually appears to be the case from pics).
Last edited by Jumpster74; 06-27-2021 at 06:49 PM.
The actual gap is ~5mm so I think it's a combo of a 2mm taller bottom seal and 3mm+ taller tophat. Pretty annoying but ill verify the ID1050x's have shorter tophats and probably get a set after that. Don't know if it's really an issue but would prefer if the injector tops didn't bottom out in the rail.
EDIT: Read the link. Yes. Yes. Yes. Thank you for knowing about those Ordering 2 sets in case I need more spacing but that's too easy of a solution to not try.
Last edited by Jumpster74; 06-27-2021 at 07:33 PM.
I've converted to return, with a spare feed line as my return instead of the evap line. I've got a DW300 and turbosmart FPR. All in, I should have enough for 400+ on e85 with a wide margin.
No idea why I have such problems. Even just testing one individual injector on a flowbench and I see the pressure drop. The flowbench doesn't give me but 3/6/12ms pulse choices. I've got something rigged up to let me test whatever pulsewidth I want. Might try using haltech to compensate deadtime off the entire pulsewidth and battery voltage both.
FWIW I run a deadheaded nb1 stock fuel system but with a wally 255hp, grams 750s, radium rail. I have enough fuel to make 400whp on 100 octane and never have issues with lack of fuel at all. Maybe your FF960s are ****?
See the blue anodized spacers in the flowforce image here. Think you might be able to buy those from them, if you'd like to run what you have. Fuel Injectors - Miata Turbo FAQ
EDIT: Read the link. Yes. Yes. Yes. Thank you for knowing about those Ordering 2 sets in case I need more spacing but that's too easy of a solution to not try.
********** ************! I've never seen those spacers in my life, I guess that's what I get for being an early adopter. My IDs pre-date FlowForce as a brand and these spacers were definitely not a thing back then. Digging through my emails I apparently sent pics of my IDs to TSE back in 2015 when they were trying to sort out some sort of installed height issue, but never closed the loop on the email thread.
WHATEVA! My solution works and doesn't leak, I guess I can advertise as "works without spacers" when I put it up for sale Good detective work there errybody.
I must admit that I don't log fuel pressure in my 99 but... My flowforce 960's are the bee's knees. I run a base pressure of 60psi, even the stock ECU was happy. I run a boost/vacuum referenced fuelab regulator between the tank cover and the return line dead headed on a stock rail. Plenty of fuel to spare running mid 11's on e85.
Figured I'd follow up as a thank you for all the help troubleshooting, but doubling up on the FlowForce spacers worked perfectly. The extra 5mm of spacers is all it needed.
Just bumped the fuel up to 60psi and the new fuel system is running like a top.
06-27-2021, 03:46 PM
0
Ordering 2 sets in case I need more spacing but that's too easy of a solution to not try.
Good detective work there errybody. 
