kevincnc

I guess it's not really a fair comparison because of our different turbos, but at 15 PSI I see between 0-2 knock counts per WOT pull per gear, and at 17 up to 5 or 6 in cool weather with 91 octane. I won't go over 17 with this turbo, and probably really shouldn't be running over 15. I don't have the V-flex yet either, but I'd say 50 knock counts is pretty low for a 20 minute session at 18 PSI. Too bad you didn't have the counter working before upgrading to V-flex. I wish more people would hook up knock counters so we could get more data.

John, I e-mailed you a couple of questions, let me know if it didn't get through for some reason.

fast951

Hi Kevin,

On 91oct, I would not run higher than 15psi boost. You can pull timing via the FQS to see how it affects the knock count. I prefer raising the fuel octane instead of drastically pulling timing out (if possible).

The beauty of the V-FLEX is the ability to program the timing curve based on boost.

I was away for a few weeks, even though I checked my emails daily, I don't recall receiving emails from you without replying. Go ahead and resend, in case I missed it.

fast951

1500F EGTs are great on the track. I assume you were running the pump gas maps? What is your knock count on the street? Does it change if you use FQS #4,5,6 or 7? As you may know, we do not have true 91oct here, so I have to make do. Drop me a note with your findings, if needed, I can redo the curve for you. But as I see it, it's fine as is.

azmi951

John, I have not had a good chance to get a knock reading on the street since I bumped up the boost. I have the FQS set at 0 and have not messed with it. In my opinion this thing is running great. Throttle response is crisp and spool is faster with the v-flex. The turbo worked awesome at the track, it allowed me to shoot out of corners and really put the power down. If you talk to Jeremy Himsel ask him his thoughts, we drove both our cars back to back.

porshhhh951

Sean you say you got 50 knock counts in a 20 minute track session at 18psi on 94octane. My question is how many knock counts is considered acceptable?

Is there just so many you can have and then boom you blow a HG? Whats the relationship between knock counts and damage to you're motor?

ehall

Hey John,,

Will you please set up a way to buy ciftcertificates from Vitesse Racing's website. I would like to have my family gift givers buy Vitesse GC's for me, but they have no way of doing so.

I'll send you an email as well.
Thanks,

E

2bridges

All I want for christmas is >>>>>>>>>>>>>>>>>>.

ehall

So here's how ya do it folks.

I talked to John. If you want folks to give you a Vitesse Gift Certificate, those who wish to get one for you need to email John. I would use John@vitesseracing.com. He probably won't have time to add a certificate to the shopping cart feature, so have folks call and give your info, etc.

One of the reasons that he gives such great service is that he doesn't waste time on purddy website crap.
So, everyone here knows just what an honorable and trustworthy guy that he is, so reassure your gift givers that all is well if they choose to get you a GC!


This commercial brought to you by ehall. I approve this message!

333pg333

Does repeated knock counts suggest an accrued damage over time? In other words how many is too many and what happens if you keep getting them even at an acceptable rate over time?
Could you tune just using knock counts and say lamba/afr? Increase boost and fuel gradually and see what happens. Fine tune with timing?

ehall

To me that's a freaking good question!
We deal in lots of absolutes, on this board. Let's talk about real world functionality issues.

fast951

You do not want any knock if possible. You use the knock sensor/system as a defensive mechanism, just in case something happens (like running higher boost than the octane permits!!!!).
When tuning on the dyno, knock will be visible if you know what to look for. AFRs and Ignition are very important, however the fuel plays a big role. It's not unheard of to switch fuel manufacturers (gas stations) and notice a difference in the way the engine behaves... There are many variables that must be identified and managed..

porshhhh951

Yes thats mainly what I was asking. Whats the relationship between knock counts and engine damage? Like could you get 50 knock counts today but, there be no lasting damge to the gasket or the motor etc?

fast951

The intensity, the severity and the frequency of the knock plays a huge role. Severe knock can destroy the engine in no time. Occasional "light" knock is not good but will not kill a engine, however it must be dealt with. Ideally, no knock is present. Now the $1M question, is how do you get the data out of the KLR. The KLR Knock Y/N output shows you a narrow view and will not give you the big picture...

porshhhh951

So what are all these guys using to sensor knock I keep hearing about? Aren't they all plugging into the KLR? Maybe they have something else wired up?

John I need you to make a knock counter/display so I can buy it. I've already got plans to buy you're wasted spark system so I can controll my timing and adjust it better for E-85.

My car is going to be nothing but, Vitesse before this thing is overwith.

fast951

So did you get your car yet? Or are you having too much fun in NY ?

There are a few things in the work, that "might" find their way to the 951 market. However this will be for another thread, I want to keep this thread limited to the V-FLEX.