General Supercharger Thread.

Boost battle, apologies if it is a repost:
https://youtu.be/h4OHdC3nAFk

 

My cobras had the Eaton with nitrous then I moved to the Kennebell awesome motors in those. I was building a custom twin turbo kit before I sold it.

 

I’ve got the 650’s and I think it’s going to be cutting it kind of close. Been seeing 90% duty cycle. I tried doing a log yesterday with the new 450 pump but when I got into WOT the truck did some weird shit where it felt like it cut fuel. So I told OTT we should wait till I get the fuel lines and pressure regulator hooked up today or tomorrow. I’m not 100% sure which line that boost/vacuum line on the regulator connects to.

 

I installed the 750cc injectors, the RFC throttle body, PS intake, 2.3 pulley and the bigger intercooler. The tuner is set up for Monday, I guess I will be towing to them, this thing is dumping fuel and I don't want to mess anything up by driving 40 miles to them.

 

Did it fall flat on its face, cut all power and give you a dead gas pedal for a couple seconds?

 

I let off as it happened and coasted for a little and was too scared to try it again. I figured since I will have the fuel lines and regulator getting delivered yesterday and today, I’ll just wait to be on the safe side. You guys know way more than I do, would you know where the vacuum/ boost line on the fuel pressure regulator needs to be connected to on the Harrop? I’ve been researching all morning

 

Ok, was just wondering if you were having the weird intermittent cut out issues that myself and @boringdriver have experienced. The FPR is boost referenced to the only open boost port on the blower (to my knowledge) which is the brass barbed fitting toward the rear drivers side of the blower, which is also where your boost gauge would be hooked up if you have one (and the brass barbed fitting would then subsequently have been removed to tee in a couple things.)

 

That was the first time I had it so that on a WOT. But ya it did feel like it cut fuel almost like back when I used to have VFtuner because it shifts based on vehicle speed instead of output shaft speed and with the 5.29’s I had to move all the shift points with 100% throttle because it would hit the rev limiter

 

I’m just saying, maybe it is related to the MAF of TB harness and not your fueling at all. I’m still suspect of mine but haven’t tried swapping them yet to new ones. It didn’t happen to me for a while.

 

I’m not using the TB harness adapter. I took mine out after it kept throwing that code. Since I was able to make it reach I’ve just kept it like that. Hopefully if Amazon drops the last package off in time I can try it again and have an update. hopefully the regulator is the solution.

Even if I had to just shift every gear at 5500 I would do it. The normal drivability is really nice with the 75mm

 

The IAT breakout loom/MAF connector would be the more likely culprit actually. So what Is your current fuel pressure regulator situation? Do you have the modified FPR that came in the kit installed, and is it boost referenced? What is the Amazon package you’re waiting on?

 

Ya I just have the FPR that came with the kit. I ordered the evil energy 6AN FPR,lines, and fittings

I also ordered plugs because i think I’m about at 15k miles on these ones.

 

I’d be hesitant to use an aftermarket FPR because they usually bleed down the fuel pressure when the truck is off. The stock fuel system maintains pressure after shut down so there is always pressure on the lines for startup. An aftermarket FPR could lead to extended crank times at startup while you wait for pressure to build, pretty sure the tundra fuel pump only gets power once the starter is cranking. Prospeed actually makes a jumper of sorts for use with aftermarket FPRs to energize the pump in the ON position of the ignition, but then if you get in an accident and the fuel system has a rupture somewhere, the pump can keep running and pumping all of the fuel out of your tank which is hazardous.

 

Is it weird that I'm really excited for this to be tuned?! Haha the combination of 'happy bits" is amazing!!

 

This. You effectively have to calculate gear and its specific ratio vs rpm to determine what speed you'll shift at, and then adjust so your result is below your fuel cutoff limiter.

Not to mention Toyota's implementing of their fuel cutoff results in dead pedal weirdness until the tach falls to a pre-determined level

 

Is it some type of check valve in the rail or return line? I hadn’t of that issue.

 

I personally don’t know the design difference that the stock one holds pressure and the aftermarkets dont. It’s the FPR itself not an external check, so there must be a check in the factory FPR.

So I did some digging up of old posts by the very knowledgeable Matt Smith on Facebook. Just for you! Here is some pertinent info on FPRs:

Factory FPR without boost reference - 43psi at all times.

Modified Harrop provided FPR with boost reference - 33psi at idle and in full boost will be about 50psi.

OEM FPR supplied for an FFV truck with boost reference - 46 psi at idle and about 60 psi at full boost.

OEM FPR supplied for an FFV truck without boost reference - 50psi at all times.

On a stage 2 Harrop with a 450lph, He hooked up factory fuel rails in parallel with a factory FFV regulator on each rail and the tuner said it had TOO MUCH fuel being boost referenced, and actually had to tune it without boost reference to cut back on the fuel a bit. Here are pictures he posted for reference.

If anything I’d try doing that if I were you. Order 2 OEM FFV regulators and figure out how to pipe it all together in parallel.

 

Good to know about the boost reference could possibly be too much.

 

Indirectly explains the new conrods:
https://youtu.be/C_YNn3ZkJmU

 

Anyone know if he ran it factory into the bucket and measured ? I'd like to see it.

You're not getting more fuel hooking it up like this but you are getting better pressure (consistant) at each injector, thats a good thing. Keeps the last injector from getting starved for fuel. The limiting factor would be the injector itself.

 

Viktor told me you just run the boost pressure line to the regulator and now it's boost referenced. I haven't done that but plan to. Not sure how much of an increase that gives.

 

Did the 750s come with the injector data for tuning?

 

On sale if anyone needs one.

AEM 30-4406 -30-35 PSI Boost Gauge

$153 AEM 30-4406 -30-35 PSI Boost Gauge

https://www.amazon.com/dp/B001DX7KMY

 

No sir.

 

@4firemandan I saw on the Toyota Repository thread you talked about scaling the injector constant and inv constant for your 650 injectors, did that end up working for you?

 

Mine came with a flow test sheet

 

But it doesn't give injector constants and shit like that?

 

Ignorant question incoming:

If the passenger side fuel rail tends to run lean, would it make any difference at all to put the higher flow tested injectors on that side and the lower ones on the driver's? Even though they're only like a few cc apart

 

I don't think it'd make any difference. The pressure loss will happen regardless since those injectors are down stream.

Maybe those injectors would unintentionally try to flow a bit more, so I guess it couldn't hurt but waste of time imo.