11 12 13
Patientzero
Patientzero Dork
4/24/22 11:40 p.m.

That is alot of fuel pressure, who is recommending that?  I'd run pressure somewhere in the 40-60 range with a boost referenced rising rate fuel pressure regulator.  

V6Buicks
V6Buicks Reader
4/25/22 11:32 a.m.

I can't wait to see the new garage!  That procharger is gonna be sweet too.

Mustang50
Mustang50 Reader
4/25/22 12:01 p.m.

Good to see you posting again.  I have a basically stock 3.8 does that mean I have more choices for a supercharger kit?  Also what do I do about the 20 year old cats?  Will removing them hurt my low end torque?  I always heard you need exhaust back pressure to maintain good torque.

KentF
KentF Reader
4/25/22 9:28 p.m.

In reply to Patientzero :

When you are right - you are right. And you are right - Thank you. The pressure should be more like what you suggest. I talked to Tom at Supersix this morning and he mirrored your advice. He also added that I should have a conversation with my tuner (VMP) before buying anything beyond the Procharger kit.  Since they have tuned this engine with these mods many times before they will have history with specific injectors and they will already have worked out the final tunes (or something very close) with the flow curves for those units. I did not know that, but it makes perfect sense. It will save time and iterations on the tune. 

He also mirrored your comment on the fuel regulator with the boost reference. I asked why that was needed with the new set up verses the original.  His answer it is already there but all the components are know entities. They use the fuel pressure sender on the fuel rail to have the computer alter the speed of the fuel pump. This will give a constant, or at least known, pressure to the injectors. But the OEM knows the pump curve. They know the injector curves. As a result, have complete control of the fuel delivery.

But now we have changed everything.  Different pump with different curve (Voltage verses Pump RPM verses Flow verses Pressure are not known). A similar discussion applies to the injectors. Furthermore everything is "overclocked" and closer to spraying parts than the conservative OEM design.  

So the next call is to VMP and then to put in an order for the tune.  Kit should get ordered tomorrow.

KentF
KentF Reader
4/25/22 9:31 p.m.

In reply to V6Buicks :

Thanks.  I have had some cabinets from the Habitat For Humanity Re-Store out there for two months. Time to hang them soon. This garage has a third bay but it is shorter than the main bay and not very wide. Still working out how to lay it out.

KentF
KentF Reader
4/25/22 9:59 p.m.

In reply to Mustang50 :

Yes and no.  You can go for a standard Procharger kit which will include everything needed.  I would also add some instruments like wide band gauges to monitor things are working OK. Find a distributor near you, or, give Supersix a call. Tom will talk you through what you need and don't need.  

Back pressure. Back pressure gets the credit but scavenging pulses is what is happening.  With a more open exhaust your car will make more power at higher RPMs. A more open exhaust slows down the velocity of the exhaust gasses.

That velocity, that inertia, creates a slight low pressure area in the exhaust port when the valve snaps closed. Think of it like a water hammer. That momentary low pressure zone in the exhaust port helps pull exhaust gasses out of the cylinder when the valve snaps open again (IF it is still there, timing is everything). This is effective at lower RPMs through a certain range. At higher RPMs the timing is off and/or the effect is overwhelmed by restrictions to all that flow.

Will removing the CATS affect low end torque? I am not sure, I did it all at once with the long tubes. It will definitely help high end power. But that is not the weakest link with these 3.8 engines.  The weakest link is no grunt at the low end. 

I do know this - When I put on long tubes with 1.5" diameter runners with high flow cats the midrange and high end was very noticeably better. The low end was noticeably worse.  

Removing cats with no other changes? Not sure. More research advised...

 

Mustang50
Mustang50 Reader
4/26/22 12:09 p.m.

In reply to KentF :

Wow!  I knew I asked the right person.  Looks like I have some decisions to make.  Thanks for the help

Stay safe!

KentF
KentF Reader
5/29/22 11:42 a.m.

Large Packages and Lawyers

I was alerted to the presence of a Fedex delivery by the dog barking. Excusing myself from an ongoing Teams meeting I went to sign the receipt for a five foot long box standing outside the door. The supercharger has arrived!

First impression after dragging it inside: How can anything this heavy make my car go faster? The shipping weight on the box was 100 pounds. Rounded up I would expect but, 100 pounds on the front of the car is significant. Egad! What have I done?

This gets back to earlier discussions of things that only theoretically make your car faster. More power is great, but there is a penalty. Part of the price is more weight on the front tires. Time will tell…

The box was nicely packed and everything fits in the used cabinets that I finally hung in the garage. It is roughly sorted in order of installation. We had a couple of rainy days so I set about getting the garage more organized for some serious project work. A lot of work to go yet but it could now be considered a viable workspace.

So, this is the “Tuner” package from Procharger for this car – fuel systems mods not included. I could also call it the “Lawyer” package. Because the car is modified well beyond stock Procharger does not have control of the engineering, particularly around the fuel system. If your engine overruns its fuel system it will run lean. Lean is hot. Lean is detonation. Lean melts piston tops.

Procharger does not want to hear someone blaming them for burning down an engine so, with the stock package, they also provide modifications to the fuel pump and new injectors. Even if some of these changes might be unnecessary, or if there are simpler ways to do it; this gives them back that control of the engineering (specifically the fuel delivery in this case). With a modified car they still would not have control with their new fuel pump and injectors because they can’t predict how much fuel the modified engine might need. So, they very specifically do not include the fuel mods. It does not solve the problem of the lean engine. But it keeps them from having to talk to lawyers.

My garden tractor has a special position on the key switch with pictograms of backing over small children. To reverse the machine with the blades spinning you must move the key to that position, press a button with a warning symbol on it, and then a red light comes on. It will not, in any way, keep something horrific from happening. But it gives the manufacturer a defense in court; “We told you not to do that.” That is a lawyer switch.

Why am I writing about this? My engine is highly modified and yet the OEM fuel pump will remain intact. As per consultation with my tuner, VMP, all it needs is a voltage booster and new injectors.

I will not be dropping the fuel tank and monkeying around with the pump. In this HP range of 350 to 420 (depending on who is talking) the OEM pump, with the stock non-return set up and OEM sensors will work just fine with a boost to 18.5 volts. I hope they are right; they have done this before with very similar strokers from Supersix.  The dual widebands I am installing will tell the story. We will see…

The advice from Patient Zero was spot on that I should look closer at the fuel system and how it is controlled. It just turns out the method for Mistress is different. That is not surprising since this car is quite different than that grey beast he is running. Everyone’s situation is different.

The advice I got from Tom at Supersix was also spot on: Contact the tuner and see what they want you to do for the fuel system. What injectors do they have curves for? Turns out they have curves for Siemens DEKKA 60LB Injectors. The voltage booster is a VMP product. These parts will arrive this week.

Soon, very soon, Mistress will become a little more beastly.

GCrites80s
GCrites80s Dork
5/29/22 1:53 p.m.
KentF said:

Large Packages and Lawyers

 

My garden tractor has a special position on the key switch with pictograms of backing over small children. To reverse the machine with the blades spinning you must move the key to that position, press a button with a warning symbol on it, and then a red light comes on. It will not, in any way, keep something horrific from happening. But it gives the manufacturer a defense in court; “We told you not to do that.” That is a lawyer switch.

I just found out last week I can mow in reverse if I manually hold the blade switch up while in reverse. This took over ten years of use to find out.

Mustang50
Mustang50 Reader
5/30/22 9:31 a.m.

Very interested in this installation, please keep us posted.  Unfortunately NEOhio region does not have an autocross site yet, so I'm not sure what I'm going to do with my Mustang.

KentF
KentF Reader
5/30/22 9:52 p.m.

In reply to Mustang50 :

Did NE Ohio lose Toledo Express?  That was a nice site.  My region lost K.I. Sawyer this year. There is some sort of big development going on there now. The good news is that my other region is keeping Wirtsmith at Oscoda.  

Mustang50
Mustang50 Reader
5/31/22 12:09 p.m.

Toledo Express was used by NWOhio region.  The lot used by NEOhio region was recently repaved and marked.  No news on the status of this one or any others.

KentF
KentF Reader
5/31/22 2:55 p.m.

In reply to Mustang50 :

Ahh... East, west issues on my part. One of the biggest problems in this sport is finding and keeping venues. 

KentF
KentF Reader
5/31/22 2:55 p.m.

In reply to Mustang50 :

Ahh... East, west issues on my part. One of the biggest problems in this sport is finding and keeping venues. 

11 12 13
Our Preferred Partners
kjbrmkwK2X1URJ4T4KrrR6qvoCneElYU1nJvEmvdVNMvi95BXpJkA29PtD6AYJmt