One last shot... Breaking up!

BoostedSUV

BoostedSUV

Active member
Re: One last shot... Breaking up!

Dummy me... I used doing MSDs on V8 stuff! I will check that but that's not causing my issue. The MSD came from Jaime Hacking and I don't what he had it one but I will def check that
 
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turboj91

New member
Re: One last shot... Breaking up!

Quickstop [UK] said:
I would get an oscilloscope onto the injectors. I really want one bad after the signal I saw on my truck one time. I think in this instance it would be revealing.

That would show the voltage on them as the rpm increases. You could tie it into your ignition as well.

That would really show you what you were getting rather than a VM.
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Somewhere previously I mentioned I wish I could read every aspect of every function in real time and reading the injectors would be included. It's funny that, from across the pond you are thinking like me. Good stuff!!!

Thanks Wyo for the reply. I feel better now. I previously has a theory that the injectors were going lean for a short time and then recovering. When I saw the flow #'s by SloGN is when I started to walk toward the podium. My theory did not involve them loosing power needed to fire though. It was more about reaction time, fuel demand changes, ability to flow at less than max wide open ect... I guess part of my theory still applies (the inside mechanical end of it anyway). I even had the part about the change in fuel pressure nailed down and that still applies in my theory and this situation. So I guess I was not out in left field. Now if only I could take back part of that hat I ate. It's really causing me digestive tract problems.

Matt, with some of the new tests you have to go thru, it seems that another pair of hands would be helpful. NJ is not far from CT (I can tell when the wind blows - haha). I could ride down if you want. I can't tell you how many times I've towed down to Englishtown and Atco so making the trip without a 35'+ trailer behind me would be a breeze. And my Prius gets 48-52 mpg. Let me know.
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: One last shot... Breaking up!

turboj91 said:
It's funny that, from across the pond you are thinking like me. Good stuff!!!
Click to expand...

I was an electrical engineer in a previous life so this problem has me very intrigued.

I have been browsing oscilloscopes and there are plenty of great options. I will probably add one to my toolkit at some point.

If it really is at a specific RPM due to fuel injectors then there will be something visible either on the spark side or the injector side. That will start pointin the finger at the smoking gun....

Ther must be an auto shop nearby that has a tool for looking at waveform and voltage on the injectors and the plugs.

Wish I could help on that...

I really miss messing around on my truck :(
 
WyoSyclone

WyoSyclone

Active member
Re: One last shot... Breaking up!

Quickstop [UK] said:
I was an electrical engineer in a previous life so this problem has me very intrigued.

I have been browsing oscilloscopes and there are plenty of great options. I will probably add one to my toolkit at some point.

If it really is at a specific RPM due to fuel injectors then there will be something visible either on the spark side or the injector side. That will start pointin the finger at the smoking gun....

Ther must be an auto shop nearby that has a tool for looking at waveform and voltage on the injectors and the plugs.

Wish I could help on that...

I really miss messing around on my truck :(
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Yup, an O-scope would be one good way to get to the bottom of this one :tup:

I used to have a really cool one that Radio Shack used to sell.... it was really cheap and hooked up to the laptop with a simple software program.... it was great for stuff like this, was very portable, cheap, and was pretty close in readings to some of the big stuff we had at our company... I might try to find another one of those :D
 
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BoostedSUV

BoostedSUV

Active member
Re: One last shot... Breaking up!

J you drive a Prius? Forget it, you just lost of your credibility! :D

If you would be willing driving down that would be awesome... Another set of eyes, ears, and hands cannot be a bad thing! I feel like I'm running around circles with this truck and getting no where. We have certainly eliminated a lot of "what ifs" but not the one that counts yet. I have a friend from CT and it takes him about 3 hrs to get to ATCO and I'm an hour and 40 mins north of atco, 35 mins north of englishtown. My mom has done some work in CT and I think she said its a little over a 2 hour drive. (Traffic depending of course).
I'm continue to work at it the problem but if you have a free weekend and I do as well I would really appreciate another brain to work with. My diagnostic abilities are limited, but my tools and access to tools are not.
 
thunderace31

thunderace31

New member
Re: One last shot... Breaking up!

WyoSyclone said:
x2 ... if it's not it needs to go directly to bat + and -
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Ok I just have to step in here The ground side of the MSD should go to the back of the cyld. head. Its been proven over and over that doing this completes the circuit with the engine better and is worth 15-50 hp depending on the app. I changed this on my 540 Big block with an MSD 7al and bam! Car went 2 tenths faster! DO a search on the net about it and youll see many top engine builders have just found this out and most NHRA Prostock cars have been doing this for years. Power should come Direct from the battery thought :tup:
 
BoostedSUV

BoostedSUV

Active member
Re: One last shot... Breaking up!

The MSD is wired to the Junction block... That's a direct feed from the ALT. I've got enough things wired off the battery! The electric fan, audio AMPs, feed to the ALT, and down to the starter. I have two 4 ga cables, and 8 gauge, and at least 2 10 gauge wires coming off the (+) terminal. I don't know if I have room for more
 
BoostedSUV

BoostedSUV

Active member
Re: One last shot... Breaking up!

thunderace31 said:
Ok I just have to step in here The ground side of the MSD should go to the back of the cyld. head. Its been proven over and over that doing this completes the circuit with the engine better and is worth 15-50 hp depending on the app. I changed this on my 540 Big block with an MSD 7al and bam! Car went 2 tenths faster! DO a search on the net about it and youll see many top engine builders have just found this out and most NHRA Prostock cars have been doing this for years. Power should come Direct from the battery thought :tup:
Click to expand...

So you're saying that if move the ground on my 7AL-3 on my dragster that runs 7.1's at 187 from the chassis to the block I can go 6.90's??? Lol just kidding. :D
 
WyoSyclone

WyoSyclone

Active member
Re: One last shot... Breaking up!

thunderace31 said:
Ok I just have to step in here The ground side of the MSD should go to the back of the cyld. head. Its been proven over and over that doing this completes the circuit with the engine better and is worth 15-50 hp depending on the app. I changed this on my 540 Big block with an MSD 7al and bam! Car went 2 tenths faster! DO a search on the net about it and youll see many top engine builders have just found this out and most NHRA Prostock cars have been doing this for years. Power should come Direct from the battery thought :tup:
Click to expand...

Yup, you're right on that one... I've just been searching the net for MSD info and that seems to be the thing to do....
 
WyoSyclone

WyoSyclone

Active member
Re: One last shot... Breaking up!

BoostedSUV said:
The MSD is wired to the Junction block... That's a direct feed from the ALT. I've got enough things wired off the battery! The electric fan, audio AMPs, feed to the ALT, and down to the starter. I have two 4 ga cables, and 8 gauge, and at least 2 10 gauge wires coming off the (+) terminal. I don't know if I have room for more
Click to expand...

Matt, you may want to get a power distribution block.... run an '0' gauge from the battery to it, then you have many terminals to connect whatever you need to.... makes it much easier!
 
leadfoot

leadfoot

Member
Re: One last shot... Breaking up!

BoostedSUV said:
The MSD is wired to the Junction block... That's a direct feed from the ALT. I've got enough things wired off the battery! The electric fan, audio AMPs, feed to the ALT, and down to the starter. I have two 4 ga cables, and 8 gauge, and at least 2 10 gauge wires coming off the (+) terminal. I don't know if I have room for more
Click to expand...

That being said, I would disconnect all luxury wiring and only have what is required for the truck to run. Whatever is on the battery and/or alternator. Stereo, alarm or any after market add ons.

It would eliminate possible variables.
 
thunderace31

thunderace31

New member
Re: One last shot... Breaking up!

BoostedSUV said:
So you're saying that if move the ground on my 7AL-3 on my dragster that runs 7.1's at 187 from the chassis to the block I can go 6.90's??? Lol just kidding. :D
Click to expand...
Hay try it ya never know worked for me an 2 buddies also all saw gains of 1-2 tenths in the 1/4 :tup:
 
BoostedSUV

BoostedSUV

Active member
Re: One last shot... Breaking up!

thunderace31 said:
Hay try it ya never know worked for me an 2 buddies also all saw gains of 1-2 tenths in the 1/4 :tup:
Click to expand...

The problem with that is the motor isn't grounded well as it just lays on powdercoated frame rails. I actually had to run a ground cable to the block bc the starter turned very slow.
 
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turboj91

New member
Re: One last shot... Breaking up!

Going backwards, Matt, when you did the engine rebuild the first time, what if anything did you do to the truck when the engine was out? Did you paint anything or powercoat the frame at that time? Something happened at that time. Think of what you did. Even spraying paint into threads of a bolt hole could cause issues with proper grounding.

Question for Wyo. Shouldn't injectors be shielded for interference like what we are thinking? They have to live a life in extreme circumstances in many ways. Your thought plays right into my mechanical theory so I'm not bashing, I'm just curious.

Matt, I make it to Englishtown in 2.5 hours so your house should be a breeze. If your having second thoughts about my Prius (at least it is not Jeff Dunham blue), I could drive my supercharged Impala SS, my Twin Turbo Supra, the Sy, the L78 Chevelle SS396, a Monte SS or something else. I wouldn't want to gay up the neighborhood!
 
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