pipo

Hi Guys,

im dont know anything else to do anymore. My Name is Philipp, im From Munich Germany i drive a Mustang 2007 GT Convertible. I Recently installed Ford Racings Hot Rod Cams in my Pony(myself). So far i probably did a mistake with holding the timing chain in place and hokding the Tensioners in Place. Which led to the left Chain skipping a tooth on the Crankshaft Sprocket (i suggested).
I Only recognized that due to the fact that the idle was bouncing from 700 to 850 RPM. And Most of all that it felt like a Brick underneath my Brake pedal.
I first thought that this Problem came from the high lift Valve Turns.
I brought my Pony to the Garage where they did the whole Procedure-> disassemble Engine Front Cover reseat Timing Chain, replace Tensioners and so on and so on. I got my car back yesterday and the Engine runs a lot better now, unfortunately tho the Brake Issue still persists.
Its like i have to use 3000lbf to brake after pushing it down 2inches.

I wont believe that these Cams need an aditional Hydrobooster cus i never read of any similar Problem relating the Cams on any Forum. I even talked to a Ford Racing Tec Guy who said they never had such a Request.

I dont know what to do anymore, i already checked the Brake Booster Lines and it seems to be closed, so no Leaks at first sight.

Do u guys have any Suggestions what else i might try/check/repair or w/e.

Thanks a lot
Greetings from Germany

hammeron

if the brake problem started when the cams were changed, then it does sound like a vacuum leak to me. you could hook up a vacuum gauge to get a reading. at idle i see -15 in/mg.

Derf00

Just to be clear, the engine was tuned after the new Cams were put into place?

With respect to the braking issue. It sounds like there is no vacuum at the brake boost. Have you followed the line of the brake booster to check for cuts or checked to make sure that you have brake fluid visible in your reservoir?

808muscle

Gotta be a vacuum leak somewhere.

pipo

Hi Guys,

thx for the Response, there is actually a slight Vaccum in the Brake Booster when i press the BRake. It just doesnt seem to be enough for a emergeny Braking. Thats when i feel the Brick underneath it.
I could'nt see(Hear) any Leaks on the Brake Booster Lines.

Hammeron, is your Vacuum Value with Cams or without. I installed a Bama Tune which was written for JLT CAI/FRPP Hot Rod Cams and german Autobahn Driving.

Cheers

hammeron

pipo, i see -15 with the Hot Rods, with stock cams i used to see -22

pipo

Do u know if i can get some of those Values with Livelink and my X4 SCT Tuner? I found some Stuff like Booster Load and Injection Pressure Drop which was always at around 39 to 40.
I still have the Problem that if i do a datalog and try to open it in Livelink all the Values are zeroed out, tho the .csv File holds all the Numbers that have been logged.

hammeron

good question. the only sensor i know of that has vacuum or boost on it, is the FRPS (fuel rail pressure sensor). i have never logged it, so i do not know if it shows more than fuel pressure.

you might just have to purchase a cheap autolite mechanical vacuum gauge, to see what your value is.

pipo

Hi Hammeron,

i checked the Vaccum yesterday with a Mechanic who had a Gauge. It showed around -14in/HG and was sometimes bouncing at around -13-12in/HG
I think that should be barely enough for brake booster Operation or am i Wrong?

Phil

jsimmonstx

Bumpy cams usually don't provide enough vacuum for power brakes to work properly (you need about -20in). If your search for a vacuum leak yields no results, you may have to add a vacuum reservoir to your setup. They're about $65 from Summit.

You can get a vacuum gauge from Advance Auto Parts for $20.