My 97 SOHC 5 speed swapped sport street/drag build

[4pointslow]

datalog

Datalog Fuel PW in clock tics & time between pip edges in clock tics with live link
Then use this formula
Fuel PW in clock tics / (number of cylinders x time between pip edges in clock tics)

That will tell you what the duty cycle is on the injectors, if you are maxing them out you will hit around 100% duty cycle.

 

[4pointslow]

Strategy

See if you can find out what your PCM strategy number is with the X4.
That number is used to choose what "PIDs" you will record in LiveLink.
Was your truck originally a 4.0 SOHC or OHV?

Upgrade that Fuel Pump, get an adjustable regulator and bigger injectors, they are all needed for the amount of power increase you are shooting for.

What turbo kit are you planning to use?

 

[2000StreetRod]

braided stainless flex lines

. . . As far as the fuel lines go, they are the same stainless hard lines and braided stainless flex lines so they'll hold any pressure you put to them. . .

Have you upgraded the hose in the fuel pump assembly?

Have you upgraded the hose from the fuel tank to the frame rail?

 

[Twisted1]

Mine is a factory SOHC that I converted to a 5 speed and Im running the original PCM. I haven't decided on a particular turbo "kit" as of yet. Most likely it will be sourced separately and all the pipes will be fabbed accordingly. I haven't even decided if I'm locating it under the hood with an intercooler or mounting it remotely without an IC. The injectors and fuel pump were supposed to be upgraded over the winter but after doing another fuel pressure test today it's looking like I'll be doing the fuel pump sooner (this week). 4pointslow, what are you running for an adjustable FPR and are you still using factory rails or did you upgrade to aftermarket? Well I guess the first question is are you a return or return less fuel system?

 

[Twisted1]

Have you upgraded the hose in the fuel pump assembly?
View attachment 85161
Have you upgraded the hose from the fuel tank to the frame rail?
View attachment 85160

Not as of yet, my external lines were in good shape so there was no need to swap or upgrade them. The internal lines I have never looked at but I will be within the next week or 2. I did another fuel pressure test today and idle pressure was 29psi, over 3,000rpm it dropped to 24 psi so I've at least figured out my issue. I changed out my fuel filter and found A LOT of water and dirt in the system

This is just from the 3 months it sat the end of this winter after I lost the first engine.

I swapped the filter and did a second pressure test and it came up but not enough. Now it reads 30psi at idle and bumps up to 35psi at 3,000rpm then drops off a little as the rpm's get higher. I did manage to take it for a test run after the filter change and it seems to have gotten rid of the stumble at high rpm shifts. My MAF counts are still staying right around the 920 mark so that most likely isn't my issue right now (pic of my data log after the filter change)

For now I think I'll leave the injectors and MAF alone and upgrade the fuel pump and FPR. That should cure the issue for good along with draining and cleaning out my fuel tank.

 

[4pointslow]

4pointslow, what are you running for an adjustable FPR and are you still using factory rails or did you upgrade to aftermarket? Well I guess the first question is are you a return or return less fuel system?

I have the rpcaster kit fuel rails.
www.bansheesuperchargerkit.com

I have a return system, and I use a Mallory fuel pressure regulator.
Walbro Fuel Pump I got from Summit racing.
I am running the factory fuel pressure approximately 39.15 psi engine off pump running. Drops to about 29-30 psi at Idle with 20 inches vacuum, goes up to about 56-57 with 16-17 lbs of boost.
The Mallory fuel pressure regulator is adjustable( It is good for up to 100psi) and rebuildable.
There is also a boost/vacuum reference port so it lowers fuel pressure when the throttle plate is closed to compensate for high manifold vacuum like the factory one does. It also raises fuel pressure in proportion to boost. I had to seal the adjustment screw threads because they were leaking vacuum/boost but most adjustable regulators have the same problem.
The one thing I have not done yet is the fuel lines. The flow through mine is probably maxed out, If you are planning on making 400-450 you will need to increase the size (inside diameter) of the fuel lines, that was what 2000streetrod was probably thinking. I know Ahodges and Dono have done their fuel lines, they both have V8's though so the parts may not be exactly what works on ours or maybe they are - not sure since I have not done mine.

 

[Twisted1]

When the time comes for bigger lines it will have all new stainless hard line and braided with all AN fittings along with a fuel cell. I'm toying with the idea of seeing how much hp my stock block will take before failing and having my second engine all built and ready to drop in. I ordered a Walbro 255lph pump tonight (I love summit!) And I have an NHRA/IHRA approved sealed battery box on its way also. The battery is being relocated to the hatch area so it has to be in a very specific sealed battery box, vented outside and I have to install a battery master switch on the back end of the truck now. I guess I'm all in at this point, it's almost time to see what it'll do!

 

[4pointslow]

Battery relocation

Please post pictures of your battery relocation installation.

I have been considering that modification and if I ever end up needing more room in the engine compartment for a larger water meth or intercooler tank I may just do it.

There is an adaptor for the fuel pump to attach the walbro to the explorer sending unit assembly. That is if you get the pump with the larger connector and your sending unit assembly has the smaller one.

 

[Twisted1]

I'm moving the battery to get some more weight transfered to the rear and also to open up some real estate for the turbo. I'm going to be pulling all the ABS out over the winter also and hopefully have plenty of room at that point for the turbo and piping. If not it will be mounted remotely under the truck. The biggest issue I'm having with the battery relocation is having to drill/cut into the body to install the switch. Keep in mind if you do relocate you'll have to do the same to be compliant with NHRA and track rules. You also need either the Moroso sealed plastic battery box or the summit equivalent. Both were $67.99 so I went with the known brand. There are other usable box's that go up in price from there, just be sure they say IHRA/NHRA approved on them. I'm hoping the fuel pump works with no other parts because the install kit for it is back ordered almost a month.

 

[Twisted1]

The part # on the fuel pump I ordered is WALBRO GSS342BX
And this is the battery box I got

 

[4pointslow]

battery relocation

That looks like a nice box, if you have a part number please post it for future reference.

Did you order a switch yet?
Maybe you can mount the switch on the rear bumper instead of drilling a hole in the body?

 

[Twisted1]

That looks like a nice box, if you have a part number please post it for future reference.

Did you order a switch yet?
Maybe you can mount the switch on the rear bumper instead of drilling a hole in the body?

The rear bumper is coming off in favor of a light weight panel/rollpan of some sort. I've got Hella Marine battery switches on the shelf at our marina which is what I've used on all my previous builds. They have a removable key that makes it a security feature also. Shut it off and take the battery key and good luck hot wiring anything

This is where I mounted it on my mud drag truck. left side of the pass tail light where the hatch would normally be. I cant mount it in the same place on this one

 

[Twisted1]

Battery box part # is MOR-74051 through summit

 

[Twisted1]

Battery box and fuel pump are here!

I'm waiting for a few more pieces to come in and I'll be spending all next week on upgrades before the dyno

 

[Twisted1]

No clue why all those pics are upside down? They're all right side up on my phone

 

[Twisted1]

99mm tb

This thing is massive!

 

[2000StreetRod]

Fuel injector sizing

A 920 MAF count with your stock 55 mm MAF sensor corresponds to 23.7 lbs air/min or 1422 lbs air/hr. Assuming a WOT AFR of 0.8 lambda (11.8:1) that equates to (1422/11.8 =) 120.5 lbs fuel/hr. With 6 injectors the requirement is 120.5/6 = 20.1 lbs fuel/hr per injector. I think the max rating of injectors is at 85% duty cycle. Assuming that then your 24 lbs/hr injectors would only be at a 20.1/(24/.85) = 71% duty cycle.

If your boosted goal is 400 rwhp and assumed drivetrain efficiency is 85% then that is 470 bhp or 78.4 bhp/cylinder. Using Stan Weiss' Table and BSFC (Brake Specific Fuel Consumption) of 0.55 for an intercooled turbocharged engine and an injector race duty cycle of 95% then you need an injector flow rate of 46 lbs/hr.

If you use 450 rwhp and an injector street duty cycle of 80% then you need an injector flow rate of 60 lbs/hr.

 

[Twisted1]

A 920 MAF count with your stock 55 mm MAF sensor corresponds to 23.7 lbs air/min or 1422 lbs air/hr. Assuming a WOT AFR of 0.8 lambda (11.8:1) that equates to (1422/11.8 =) 120.5 lbs fuel/hr. With 6 injectors the requirement is 120.5/6 = 20.1 lbs fuel/hr per injector. I think the max rating of injectors is at 85% duty cycle. Assuming that then your 24 lbs/hr injectors would only be at a 20.1/(24/.85) = 71% duty cycle.

If your boosted goal is 400 rwhp and assumed drivetrain efficiency is 85% then that is 470 bhp or 78.4 bhp/cylinder. Using Stan Weiss' Table and BSFC (Brake Specific Fuel Consumption) of 0.55 for an intercooled turbocharged engine and an injector race duty cycle of 95% then you need an injector flow rate of 46 lbs/hr.

If you use 450 rwhp and an injector street duty cycle of 80% then you need an injector flow rate of 60 lbs/hr.

You must be an engineer! Lol, that is an impressive bit of information and I am very appritiative. I did some number crunching myself and surprisingly came up with the exact numbers you did as far as injector requirements. Of course yours reads out like a Nasa manual and my method of getting the end numbers would look more like a child's drawing done with crayons in comparison. Haha
I know I don't need the 90mm MAF yet but I will soon so why buy one smaller than i need in the end to get me by for now. I would like to upgrade my injectors however putting 60#'s in there now would do more harm than good. I'm still thinking if I can increase my fuel pressure to 60-70psi so my current 24# injectors should be the equivalent to a 30# injector with stock fuel pressure. This is all based on factory specs that the 19# injectors used in the return less system flow 25lb/hr withe the 60-70psi fuel pressure.
I've disconnected the vacuum line off my FPR which SHOULD HAVE brought my fuel pressure up to the max 40psi at idle. I am going to mess around with one of my spare regulators next week and see if I can modify it into an adjustable regulator. Hopefully I can at least bump up my fuel pressure enough to fix my current problem and have it retuned correctly.

 

[2000StreetRod]

drivability

The only negative for the 90 mm LMAF is a slight reduction in drivability. There are only 30 data entries allowed in the PCM MAF transfer function table. The greater the range of the MAF sensor the larger the step size between entries. However, the PCM interpolates between points to increase accuracy. I made the steps smaller for low airflows (when the graph is most nonlinear) and larger steps for the higher airflows (when the graph is more linear). I didn't detect any reduction in drivability with my LMAF90.

I picked the Siemans Deka 60 lb/hr injectors (even though they can flow way more than I need) because they have good low duty cycle control. For a strip vehicle that is less important.

My Haynes manual states that for the return type fuel system the pressure should be 40 to 50 psi with the vacuum hose detached. At WOT your vacuum should be very close to 0.

 

[4pointslow]

vacuum line

At WOT your vacuum should be very close to 0.

Which means pulling the vacuum line off is only affecting the fuel pressure at Idle, that wont help at WOT.

Also the vacuum line is there to lower the fuel pressure in proportion to engine vacuum to compensate for the vacuum sucking on the injector tip so without it the pressure drop across the injectors will not be correct. It would be creating a problem, not fixing one.