Mach 1 Cam swap

[nickSD]

What causes it then? There's so many of us that have the whistle, that it's hard to believe that we all have a vacuum leak. I've had my intake off twice to check and recheck plus I've looked at every hose, gasket, IAC, EGR, PCV, idler pulleys, exhaust gaskets, etc. You name it, I've checked it.

I contacted Comp Cams again and they wouldn't flat out agree that it's from the cams but they basically said I was an idiot to run the stock springs. I didn't like choking that one down, but I almost have it all apart now to change the springs!

Just trying to save somebody this kind of hassle.

Of course I'm going to take the opportunity to upgrade some other things while I'm doing this. So no worries, just thankful to have a couple Mustangs to play with.

By the way, Happy Thanksgiving to all!

:beer:

 

[RideThePONY]

Your Mach just became my Machs inspiration, sounds soooo good!

 

[Robman420]

Thanks alot^:rockon:
I think the whistle sound could be the air rushing threw the intake, but it dosnt really bug me anymore as long as its not a problem

 

[nickSD]

It could be that simple. Although air is rushing through the intake with stock cams too tho.

I still think there's some sort of harmonic vibration in stock springs right at that rpm. There's some videos on Youtube that show soft springs acting like a slinky at certain rpms.

Here's a couple that are not a 4v but illustrate spring dynamics, at least:

[nomedia="http://www.youtube.com/watch?v=UTVxPFqxssY&feature=related"]Ford GT Mustang Modular 3V Stock Head - 8000 RPM Ottodyn Test - YouTube[/nomedia]

[nomedia="http://www.youtube.com/watch?v=cfGg15WgSEU"]Short Valve Float Movie - YouTube[/nomedia]

Usually it's thought that valvetrain instability happens only at high rpm, but Comp was telling me that it can happen earlier, depending on the shape of the lobe, how quickly the cam accelerates the rocker/spring/valve and sets them back down, and so forth.

My guess is that new springs would fix this. But I'm pulling my cams back out today and probably go back to running a Vortech on the car after I forged the bottom end (also doing that now). With the Vortech the car ran 121 mph in the quarter and at times would also pull down 28 mpg on the highway. Kinda want to return to that setup as it was a blast to drive. Sleepy too.

 

[1slomach]

Im about to do a cam install somewhat similar to you and Im also be helped out by NASVT but my question to you is did you change to a different mass air and are you running larger injectors.. I picked up a 90mm meter and going with either 30# injectors or 39s...

 

[nickSD]

IMO you wouldn't need those for just cams and exhaust. On the other hand I like the LMAF/39 lb injector combo. It's easy to accommodate them in the tune and they will support future mods up to 450 rwhp, nice if you go the mild boost route later.

More importantly, pick up the phone and talk to Comp Cams about springs if you are getting their cams.

 

[Boss 327]

IMO you wouldn't need those for just cams and exhaust. On the other hand I like the LMAF/39 lb injector combo. It's easy to accommodate them in the tune and they will support future mods up to 450 rwhp, nice if you go the mild boost route later.

More importantly, pick up the phone and talk to Comp Cams about springs if you are getting their cams.

90mm MAF and 39lb injectors will support more than 450rwhp.

 

[na svt]

30s require adapters, 39s do not and can probably be found for less money. A 90mm MAF isn't needed but will add a couple hp up top.

I have some 42s with adapters if you want to some larger injectors at a decent price.

 

[nickSD]

Yup, and I've been to 470 with them. But I wouldn't recommend that for over 450 rwhp non-intercooled, based on my own experience. Good to be safe if trying to make a decision. A terminator can go to 480-500 with them from what I have noticed.

90mm MAF and 39lb injectors will support more than 450rwhp.

 

[clc44]

What's an ideal injector for say 370-390 RWHP?

 

[nickSD]

You just want one that can cover that power level with some headroom, but not so big that it has trouble at low pulse widths, like at idle. I have seen 60s have a mild issue with that on my car in the past. Of course that's much too big for this.

I would say 39lb factory injectors would be the call above 350 rwhp.

 

[1slomach]

Wouldn't 42s be too large?? I will have full bolt on and the cams... hp will prob be 380 to 400 I would assume... getting a custom grinded cam, livernoise valve springs, and will be degreeing the cams as well.... I've already picked up a 90mm mass air... I've just heard so many things with sticking with stock injectors then go 30s.... anyone have a set of 30s??

 

[Bmeagher]

I did the 90 lmm, along with 39's. I ended up sending a set to Stiegemeier to have them flowed and balanced. Since i had one sticking open.

 

[na svt]

Wouldn't 42s be too large?? I will have full bolt on and the cams... hp will prob be 380 to 400 I would assume... getting a custom grinded cam, livernoise valve springs, and will be degreeing the cams as well.... I've already picked up a 90mm mass air... I've just heard so many things with sticking with stock injectors then go 30s.... anyone have a set of 30s??

39s will drop right in, 30s and 42s require adapters (EV1 to EV6) in order to conenct to the harness.

$2s are not "too large", but they aren't needed.

 

[nickSD]

Wasn't there some sort of issue with the spray pattern on certain injectors, when used on a 4v? Anyone else know of that? Might be worth some research. Wouldn't be a problem with 39s though.

 

[na svt]

Wasn't there some sort of issue with the spray pattern on certain injectors, when used on a 4v? Anyone else know of that? Might be worth some research. Wouldn't be a problem with 39s though.

24s, 30s, 39s, 42s are all good for 4vs.