The price was right so I snagged it but...

[16GoManGoHC2]

I made this video to show over reving between 3-4 shifts on my M6 when using a solid pulley on the blower or the decoupling pulley is not functioning correctly. But it also shows fuel pump duty cycle keeping up to 1100 wheel HP at 24 psi of boost in -1100 DA 40F conditions, worst the fuel delivery system has had to try and keep up with so far. Twin 295 pumps, no BAP, modified fuel line and modified stock fuel rails with ID1700 injectors on E83.

 

[Speedy!]

Did he say if he bought one like he said he was going to for testing? I would have brought up the Facebook conversation that it was your car

Also if the 2nd FPCM is a slave to the 1st then why isn't it shutting off like the 1st?

I forgot about the FB thing.

The second pump runs off the second pump relay entirely. FPCM 2 just tells it how fast to run (gets signal from FPCM1 on that purple wire). I got a video going through all that. The JMS keeps putting out volts even when power is removed. That's the problem. I've measured it with a meter and it SLOOOOWLY drops. That's keeping the relay powered up, which keeps the pump running. I'd think this is an error but I bet it has to do with how the JMS ramps voltage in and out to avoid spikes but it's taking like 9 minutes to drop voltage back to zero which seems like a long time.

JMS says this is expected and a known issue with this type of drop in fuel system. They told me yours should not work so that could mean something isn't right on yours, or maybe mine's the one that's broken? I'm trying everything to get it to work so I don't have to ask Jon to take it back or I have to try to sell it or something if he can't. I wish this issue had been publicized since it was "known" according to JMS and the folks in the FB thread as well. Yet websites still advertise this as working with a dual drop in system.



It's hot rodding and I'm good with DC electronics and actually enjoy fooling with them. A JMS engineer told me what's supposed to fix it and I had most everything on hand to make a little jumper harness to solve it. I'll hopefully know today.

@fumanchu182 those return systems get more complicated than I really want or need. I agree they give gobs of overhead but they are a PITA to put in and my OCD would make it even worse lol.

@16GoManGoHC2 you have several variables in that log that are way different from mine. Your commanded fuel pressure is 73 psi which has been lowered from 80psi stock and ID1700 injectors are giving you much overhead as well. You're still tickling over 13ms of inj pw and if the tune has stock settings for limits the bypass will open at 13.5ish so keep an eye there. I'd rather keep my fuel pressure up to at least 80psi if not higher on mine.

These things probably work fantastic on cars that came with two pumps from the factory like a Redeye/Demon/Trackhawk. I haven't found anyone else using one on a dual drop in system and with the 3rd pump add on costing like $300 (+ maybe a harness?) I can see why.

 

[covidcommander]

You’ll get it! I ended up getting really mad one day when I ran a 9.1. Went home looked everything over and found an issue. Went out the next week ran a 9.0 but my 60ft was crap (for me) a 1.36. So I went to make another pass. Found a better 60 and then 8s. I then made a few other 8 second passes before putting the car up.
hard part is once you hit 8s now where do you go?

7's

 

[covidcommander]

No tank bung tool, but I do have a mallet and a big flat head screw driver I'm replacing both pumps. I'll keep the good one as a spare and plan to disassemble the bad one to see if I can see anything that caused the failure.

What are thin section wrenches?

Tappet wrenches

 

[fumanchu182]

@Speedy! I've been down this path, unfortunately it's yeah run the BAP or upgrade to triples. For my experience when OST was tuning the car when it died at the 660, that was it. For reference here is a wot pull for me at ~20psi.


I am commanding 80psi but giving it 94psi, I should probably back that off at the regulator to 85psi (give it some head room). In some of my other tunes when I was running 104/93 mix it was commanding 94.3 to give it some head room. Since I've reset a lot of those tables that is an artifact. However my FP DC is barely up there. Plenty of room left and the injectors are barely sneezing. (This was a fifth gear pull, and I was only testing to make sure the trans was ready to rock n' roll).

I understand that you don't want to go through the PITA of the installation but eventually you'll get to where I'm at and the peace of mind is why I'm happy with it. If you want peace of mind, welcome to the dark side! 😈

 

[vortecd]

I forgot about the FB thing.

The second pump runs off the second pump relay entirely. FPCM 2 just tells it how fast to run (gets signal from FPCM1 on that purple wire). I got a video going through all that. The JMS keeps putting out volts even when power is removed. That's the problem. I've measured it with a meter and it SLOOOOWLY drops. That's keeping the relay powered up, which keeps the pump running. I'd think this is an error but I bet it has to do with how the JMS ramps voltage in and out to avoid spikes but it's taking like 9 minutes to drop voltage back to zero which seems like a long time.

JMS says this is expected and a known issue with this type of drop in fuel system. They told me yours should not work so that could mean something isn't right on yours, or maybe mine's the one that's broken? I'm trying everything to get it to work so I don't have to ask Jon to take it back or I have to try to sell it or something if he can't. I wish this issue had been publicized since it was "known" according to JMS and the folks in the FB thread as well. Yet websites still advertise this as working with a dual drop in system.

View attachment 88886

It's hot rodding and I'm good with DC electronics and actually enjoy fooling with them. A JMS engineer told me what's supposed to fix it and I had most everything on hand to make a little jumper harness to solve it. I'll hopefully know today.

@fumanchu182 those return systems get more complicated than I really want or need. I agree they give gobs of overhead but they are a PITA to put in and my OCD would make it even worse lol.

@16GoManGoHC2 you have several variables in that log that are way different from mine. Your commanded fuel pressure is 73 psi which has been lowered from 80psi stock and ID1700 injectors are giving you much overhead as well. You're still tickling over 13ms of inj pw and if the tune has stock settings for limits the bypass will open at 13.5ish so keep an eye there. I'd rather keep my fuel pressure up to at least 80psi if not higher on mine.

These things probably work fantastic on cars that came with two pumps from the factory like a Redeye/Demon/Trackhawk. I haven't found anyone else using one on a dual drop in system and with the 3rd pump add on costing like $300 (+ maybe a harness?) I can see why.

I looked into adding the 3rd pump and you can send it to tapped and they can upgrade the hat. After buying another pump it will be close to $500 when all done

 

[Speedy!]

@vortecd that's probably right, the third pump upgrade service is listed at $300 on their website, +$40 if you go with a 285 pump, but it doesn't mention the harness or FPCM so not sure on those. I have two spare 285s now so if I go that route I'm going to ask Rick to credit me for the cost of the pump since his tech told me to replace them. His tech also doesn't seem to understand the difference between gasoline and E85 fuel requirements so make sure you get Rick if you have questions about anything.

The dual pump JMS is around $550-$600 so most probably just get the third pump for these drop in systems.

Anyway, hindsight is 20/20. Here's the harness I built and according to JMS fixes the issue. Lunch and then a test drive but to be honest I'm not confident this will work based on my previous testing.

 

[jgilj]

Pretty nice looking work for a engineer 😆

 

[fumanchu182]

@vortecd that's probably right, the third pump upgrade service is listed at $300 on their website, +$40 if you go with a 285 pump, but it doesn't mention the harness or FPCM so not sure on those. I have two spare 285s now so if I go that route I'm going to ask Rick to credit me for the cost of the pump since his tech told me to replace them. His tech also doesn't seem to understand the difference between gasoline and E85 fuel requirements so make sure you get Rick if you have questions about anything.

The dual pump JMS is around $550-$600 so most probably just get the third pump for these drop in systems.

Anyway, hindsight is 20/20. Here's the harness I built and according to JMS fixes the issue. Lunch and then a test drive but to be honest I'm not confident this will work based on my previous testing. View attachment 88899

Nice harness, you cannot run the third pump off another fpcm, its not a thing. Thats when you would have to switch to the fc3 from fore. Imo if you are using a triple pump and the stock lines thats a bottle neck. -10an to a Y block then -8an to the rails. Still a dead head system so the only worry would be vapor lock.

 

[vortecd]

Nice harness, you cannot run the third pump off another fpcm, its not a thing. Thats when you would have to switch to the fc3 from fore. Imo if you are using a triple pump and the stock lines thats a bottle neck. -10an to a Y block then -8an to the rails. Still a dead head system so the only worry would be vapor lock.

We all keep making the same mistake. We buy parts for what we think we are going to do then do more.

 

[fumanchu182]

We all keep making the same mistake. We buy parts for what we think we are going to do then do more.

Thats why after duals I was like Im done. I want a system for 30psi. I even sold my duals to cover a 1/3 of the L4 kit. I wish @Speedy! the best on this adventure and not tossing shade but its a bandaid. And if it shits the bed at the track, game over, and not wishing that on anyone.

 

[ACMAVRO]

I went the jms route at first, but the fuel pump fuse would blow at high rpm on 22v. It did work with the settings turned down but I wasn’t getting any (single stock pump) benefit that way so I needed it turned up. The fuel pump fuse is a 30a and you can see that monster jms fuse is a 40a. I didn’t want to change the stock fp fuse to 40amp for below reason. After talking with the tech at jms and we could not resolve the issue, I sent it back for a credit and went with dual 285’s from tapped.

Do not replace a blown fuse with one that has a higher amperage rating. The fuse has a specific amperage rating because it is intended to be the weak link in the circuit to protect the electrical components.

 

[vortecd]

Thats why after duals I was like Im done. I want a system for 30psi. I even sold my duals to cover a 1/3 of the L4 kit. I wish @Speedy! the best on this adventure and not tossing shade but its a bandaid. And if it shits the bed at the track, game over, and not wishing that on anyone.

We all get what you are saying but most don't want to sell what they have, lose money and spend more money for a bigger system. Not saying it isn't right but just what people do.

If I had plans to run 8's last year I would have bought a different system but I didn't

 

[Speedy!]

Welp, it didn't work. Oilburner and I had some exchanges and what he and I came up with likely actually worked and was a much simpler solution that only required one wire be moved in the Tapped harness. I tried discussing it with JMS but they were insistent on doing this relay deal. I just wanted to go this extra step to know I had done everything I could. I spoke with Jon tonight (thanks Jon) and will be returning the JMS. I had it set to right at 18V on both pumps which should have done something, but the fuel pressure dropped back to the same exact place it did without the JMS hooked up. My only guess is it's bad or something so Jon will get a credit and I'll go a different route.

My car has the inj pw limit "safety" that works so that was another reason I was OK with a BAP as if it ever failed the inj pw would hit the limit, open the bypass to bleed boost, and save the motor so not a huge deal. That's what's happening even with the JMS hooked up and configured to right at 18V on each pump. That should be plenty, but it's not making any change. I'm hitting 13.6 inj pw right around 6,000 RPM and the bypass opens and bleeds about 2psi of boost to bring that down in to the 11pw range.

@fumanchu182 Tapped claims their 3rd pump can be operated via a 3rd FPCM and it's an option on the order page.

 

[jgilj]

Damn that’s a lot of work Speedy too find it doesn’t work correctly. 🙁

 

[jonx96]

I’m curious how much more steam I start seeing from my car with the full sdg kit.
a 2.85 on a 2.7 is just a little to much for stock pumps. But you seem to really be dropping pressure.

 

[fumanchu182]

@fumanchu182 Tapped claims their 3rd pump can be operated via a 3rd FPCM and it's an option on the order page.

That's interesting, however that small diameter line isn't going to flow enough fuel to the rails IMO. That restricted hard line then has to feed one rail fully before the fluid then takes the path of least resistance to the other side. At 20 PSI I wouldnt' even take that chance. Maybe and just maybe running a set of FORE rails with the Y block being fed by a -10an line routed along the same route then splitting at the Y block to -8an would do the trick.

 

[RGPIII]

Im running the tapped kit with the 3 FPCMs and it’s working perfectly. @fumanchu182

 

[16GoManGoHC2]

Im running the tapped kit with the 3 FPCMs and it’s working perfectly. @fumanchu182

@RGPIII assumed on E85? How much wheel hp you think you are at at the moment? What injectors and how much boost and air charge you seeing?

 

[RGPIII]

@RGPIII assumed on E85? How much wheel hp you think you are at at the moment? What injectors and how much boost and air charge you seeing?

no clue on the HP. Probably right around 1050-1100 I would guess.

yes E85 more specifically ethanol one R. Running 1700 injectors, whipple 3.0 making 19.5-20psi