[MickMach]

Originally Posted by Mick

Hey MichMach,
As you know I have the stock hood. Last week the insulation under the hood started rubbing against the s/c cover on the letter N on the word Saleen on the passanger side. The clearence was tight to begin with, I knew eventually this was going to happen. Dealer has two possible fixes, cut the insulation in the area of the s/c cover, or remove the insulation totally and they would order me another one under warranty and I would just hold onto it. If I take it all off I am not sure if the heat will affect the paint on the hood. The car is used on my days off when the weather is nice, and I have seen many new cars with no insulation under the hood right from the factory.

I'd remove it totally or cut it but you cut it after you get a new one under warranty...I'd get the new one and save it like you said.....just to have it. they may want the old insulation to send back but who knows on that...some parts under a warranty claim they have to send back to Ford, just depends.....
Engine heat will not hurt the paint on the hood...never ever. the insulation is there in case of a fire...if a fire occures the inslution will melt and hopefully put out the fire..a small fire that is we all ahve seen many cars burnt bad. the insulation is not a paint protector. that why some cars dont have it...like you said

[Mick]

Thank You my friend. And Happy Thanksgiving to you and your family.

[kj_cinci]

A 'stock' Saleen blown car make more low end TQ and HP than my mid 500s RWHP Vortech blown car. I do know they have that bleed but it does not bleed all the 'boost'... less vacuum is 'boost' too... What I'm saying is that at, lets say, 3,000 RPM the Saleen will be higher in the boost, WOT or not... I'm also saying that the Saleen makes more power (wear!) at 2,000 RPM...

Just saying....

[thump_rrr]

Originally Posted by kj_cinci

A 'stock' Saleen blown car make more low end TQ and HP than my mid 500s RWHP Vortech blown car. I do know they have that bleed but it does not bleed all the 'boost'... less vacuum is 'boost' too... What I'm saying is that at, lets say, 3,000 RPM the Saleen will be higher in the boost, WOT or not... I'm also saying that the Saleen makes more power (wear!) at 2,000 RPM...

Just saying....

That's incorrect.

When I'm driving down the highway at 3000rpm for example.
I'm at 20"Hg vacuum.
I need to be accelerating for it to be decreasing the vacuum or coming into boost.

[Slofoot]

Originally Posted by thump_rrr

That's incorrect.

When I'm driving down the highway at 3000rpm for example.
I'm at 20"Hg vacuum.
I need to be accelerating for it to be decreasing the vacuum or coming into boost.

Thank you Peter! 2O" Hg vacuum is not boost. Neither is 10"Hg vacuum. But instant boost is instant boost! That's why the TS blowers are soooo fun on the street.

[helicfii]

A standard day at sea level is 29.92 inches of mercury.

If you are cruising at 20 inches, you are boosted, because the cruising manifold pressure for a N/A motor will be considerably less than 20 inches, no?

Are you reading a vacuum gauge or a psi gauge- does it have a "zero" mark where you reach 29.92? "Vacuum" is simply another way of expressing manifold pressure.

If we want to know how much boost we are running at cruise, we take the N/A cruising manifold pressure, and compare it to the S/C cruising manifold pressure- the difference is psi boost.


Correct me if I'm wrong....

[kj_cinci]

Thump; You're correct and I am incorrect, on purpose... hence the What I'm trying to say is that at the get go (when most wear is put on the engine; cold, moving at 800 RPM) I'm never in the bost while a saleen seem to be there with little throttle, it closes the bleed off before WOT right? Of course it opens the bleed off and shows vacuum on highway driving, so does my Vortech...

Slofoot; Yep, instant is more fun!! Just maybe not for your motor and drivetrain?? Think that's what this thread was about?

Helicfii; Sounds good but the atmospheric pressure is 14.7 or so PSI right? The standard altimeter setting or QNE is 29.92 to show zero feet of altitude at sea level a standard day (29.92 and +15* centigrades.) But it do measure manifold pressure, like mine reads ~14 PSI at max so one could say I'm almost doubling the amount of air in my 4.6 compaired to a NA 4.6...?? Maibe we need a Euro meter measuring bars but that too would be wonky since my car loads about 1 bar while their standard altimeter setting is 1013...?? Oh my..

[helicfii]

kj_cinci: Yes, I agree that at 14 psi, you are feeding a lot of boost, since your manifold is almost at ambient, or atmospheric pressure.

But- he said "Hg", which represents inches of mercury.... my comment was more directed towards the proper reading of manifold pressure using a "vacuum gauge".

I thought he was saying that 20 Hg at cruise was essentially no boost, which I am not sure that I agree with. 10 "inches" of vacuum (or 20 Hg)could easily represent boost, depending on the gauge used, and its markings....

I apologize if I am reading too much into this....it has also been a long time since I flew recips- Some of my students who understood cars and vacuum gauges seemed to have more problems truly understanding manifold pressure on a N/A recip, since they were used to seeing negative values on a vacuum gauge, when, in reality, those values were not really negative at all- it was just the markings on the auto vacuum gauge that represented vacuum relative to atmospheric pressure. Then again, maybe I just need a vacation.

I had this professor in college who used to interupt discussions, and say, "you're fu_king the wrong thing." Perhaps that is what I am doing here...

[kj_cinci]

Yea, I see your point... I have not looked at my guage to see what it measures vacuum in. I do agree though that even in 'negative' boost or vacuum there is some positive displacement... ie. boost... my opinion...

[helicfii]

agreed.