This really excites me! I have read about Livernois in MMFF and they really seem to sweat the details. I also like the fact that they are a just a few short hours away. If these guys are really smart they would come up here for vacation too.
Welcome Rick, I look forward to many more posts.

 

 

Heck ya.
Next question. Were the original stock pulls made on same dyno as the "broke in" pulls? And how's it feel cause I know you have drove it now

 

Well said. Welcome as well Rick, you're about 15 minutes up Telegraph for me, so I know where to come and get the baseline on mine done as well.

 

Welcome and thanks for clarifying the graphs Rick, when I read the original post it had both the original and new baseline #'s, so the actual gains were properly reported. I'm still impressed with the gains you achieved with the tune.

PS, I may just have to pass by with my Boss next Spring.

 

the car is an animal now.

spins hard into 2nd and now doesnt chrip 3rd it spins into third....crazy
thats with silly big Goodyear F1-D3's too!

 

500 RPM is a huge jump in red line. Any concerns about engine longevity, or have you heard some good things about the capabilities of this motor?

 

A buddy of mine is a valvletrain engineer for the 5.0 and he says that 7,500 is "borderline"
the valves are heavy with a lighter spring for that kinda use. Once on a while is ok.
The ECU starts to have trouble keeping up at/above 7,500 with sensor input

Summary, once in a while it's ok. Don't spend prolonged time up there with the stock valvetrain (aka road racing)

Eveything else in the motor is good to 8k. A forethcoming model will addresses all the valvetrain concerns for HIGH RPM

 

motor is better than the old 4.6 im sure, and didnt people spin those to 6700 all the time with no issues? and redline was like 6200? thats 500rpm right there

 

so .... wait we talkin a 7500-8000rpm boss motor? **** thatd make me get one for sure

 

Read between the lines (or in the Boss thread...)

 

 

99/01 Cobra motors had a 7000 rpm redline. I occasionally spun mine to ~7500 rpm. Never had a problem with fuel or the ECU up there. Main problem with high rpm like that is finding a street tranny that could be powershifted up there.

 

Ya it did. The processor in that car ran outta steam as well.

You have to think about who I was talkiing to. OEM engineers are some of the pickyest people you will ever meet.
You can't feel what I am talkiing about in your butt you need to analyze data from the PCM to see what I am talking about.

 

So if I understand you correctly, this ECU is at it's bandwidth limit at 7500, so:
The processor speed is not quite fast enough to either provide the proper metering resolution (the resolution in commanded injector opening time), or at the upper RPM limit the (relative) time delay between sensor input and control actuation becomes too large to safely control the engine.

-> then the Boss will have to get a faster ECU...

With improved airflow and at higher RPM, the injectors get close to being open 100% of the time, at which point the ECU can no longer adjust the air/fuel ratio.
-> then the Boss will need larger injectors.

BUT - with larger injectors, you need higher time resolution to achieve the same accuracy of fuel metering, even at the same RPM, so this also requires a faster ECU.

As for valve train mass, valve float is an excellent rev limiter... ;-)

 

ok you read into things that I didnt say.

I mentioned nothing about injector duty cycle issues, your making an assumption there.

Nothing about fuel flow/delivery issue has been expressed to me.

The speed of the ECU to manage sensor input data is what I am talking about. Thats why it is not a great idea to raise the rev limiter.

The ECU is not at its true limit at 7500 its just close, as far as I know the Boss 302R1 race car uses this same ECU and it spins to 8k but has some trick valvetrain parts

 

When you say "Ya it did", what exactly are you referring to?

The processor may indeed be near its limit, but I know of a few NMRA racers that took stock computers (with aftermarket tuning, of course) to 8k. It may indeed have been having problems up there, but not enough to show up at the track (drag strip....know your a road racer type).

That said....I had a fellow NMRA racer friend with an 03 Mach 1 that had HELL with his processor at a much lower rpm. Don't remember exactly where, but it would briefly shut the car down somewhere just above 7k.

For me, moving the rev limiter up to ~7500 would be one of the first things I'd do. Based on what I've seen, for drag racing, this motor needs to be shifted at 7200-7300 rpm. I'd be willing to push it that high...perhaps crossing my fingers while I did it.

 

that processor had the same issue where it had trouble keeping up sensor input.

If you plan to run the car above 7,000 consistanly and for long durations your taking the life of you engine in your hands (the new 5.0 that is) with the stock vavletrain.

 

Correct, sorry. A bit foggy as I just got up. I was adding bits from my own experiences building a fuel injection system for Formula SAE.


Have the 302R1 teams had issues with their ECU's at that RPM?

 

I have not spoken with the Multimatic boys directly yet, Rehagen's new car is still on the chassis jig and the engine is still in shrink wrap on a pallett last time I saw it so I cant ask them yet.

I will start asking around this weekend at the Mid-Ohio Continental Tire Challanege race.