Ken Miele
December 22, 2014

Stang That Stumbles

I have a 2006 Mustang GT, with CAI, a GT500 throttle body, an SCT 91-octane tune, and Cervini’s cat-back side exit. When I hit the gas, a lot of time the car will stall, then take off again. My GT has an automatic, if that matters. It seems like it is starving for fuel, but I know of cars with superchargers that have stock fuel setups, so I can’t imagine that I don’t have enough fuel pump. Is it a tune problem or the TB? It did do it a few times before I put the TB and tune in.

Bill Tromble
Via the Internet

While you may have the right fuel pump, it may be going bad. There was a TSB (Technical Service Bulletin) on the 2006 Mustang GTs about this. It seems some Mustangs may have air bubbles forming around the fuel pump when cruising. Ford suggests that you have the fuel pump and assembly replaced. I would also suggest you have your GT custom tuned for maximum performance. Any time you upgrade components, a proper tune will always help get the most out of your combo.

Are Spacers Safe?

First, I enjoy the magazine and the ideas I pick up to increase the power of my ’10 Mustang GT. I just put on Baer GT Plus front brakes. I have 20x8.5 rims in the front and 20x9.5 in the rear with 40mm offset. In order to put the Baer 14-inch two-piece rear rotors on, I had to use lug-centric 8mm wheel spacers. Are the spacers safe to use, or could they cause damage to the hubs, bearings, and so on?

Joe the Racin’ Fool
Via the Internet

I do not see any issues using the 8mm wheel spacers on the rear. It’s OK to use spacers as long as the wheel studs are at least 3/4 inch or more through your lugs. You should be OK. The rule of thumb is for the wheel stud to be at least six threads deep into your lugs. Longer aftermarket wheel studs are available if needed.

Budget Windsor

I’m building a 1984 T-top GT, and I’m interested in the 351 budget-build motor you just finished. What cam would you run if not worried about idle quality? My car has a five-speed and will have a carburetor instead of EFI. I was thinking about running the old Comp Cam XE274HR. Would it work? And what size carburetor and intake would you run? I would like to reach 400 hp on the motor. Thanks for all your help.


The Comp Cams XE274H is good choice because it will provide plenty of power and torque. You will notice the lopy idle, but running a five-speed will make it very drivable. I suggest a Holley 750 vacuum secondary for the carb, and a high-rise dual plane intake such the Edelbrock Performer RPM. With a good set of heads, 400-plus horsepower is well within reach.

Three-Valve Thunder

I have a 2007 Mustang with a 4.6L. It had a few mods already on it when I bought it, including a JLT cold-air intake, Steeda pulleys, BBK long-tube headers and X-style midpipe, Ford Stinger mufflers, and a custom tune for 93 octane. My horsepower goal is 400, staying naturally aspirated. I talked to someone at a speed shop who first said the mods I want to add (Comp Cams, C&L intake manifold, and Ford Racing throttle body) would give me 350 rwhp. With a 15 percent loss at the rear, that calculates to 411 hp at the crank—hence my goal. Today I was told by someone else at the same shop that the C&L manifold and throttle body was not the way to go and I should do the Comp Cams and a supercharger. I really want to stay naturally aspirated and keep cost at or below $3,000. Muscle Mustangs & Fast Fords touts the C&L manifold replacement to 34 rwhp with a different throttle body, so I’m confused what to do.

Steve S.
Via the Internet

The C&L intake will increase power, as will the Ford Racing intake, which we’ve seen to work very well. Advantage with the FRPP is the material. Both will increase power, mainly at a higher rpm. Maybe your shop feels that it is not worth it because of the power coming in at such a high rpm. Your mods are right on track to reach your goal of 400-plus horsepower. High-rpm horsepower is not a bad thing. Ideally you want power to come in fast, but that can lead to traction issues. The 4.6 Three-Valve makes good torque for a small engine, and having that extra power at the upper rpm range keeps your Mustang pulling hard to redline. I’d also recommend 3.73 or 4.10 gears with this combination. So if you want to stay naturally aspirated and reach 400-plus horsepower, go for the mods you are planning.

Cool Tools

I am looking for a tool you had in an article for a 2006 4.6 Ford Mustang GT. It’s made by AMF or AFM. I saw it in your “Two Cam Slam” article. The tool holds the cam gear and chain up so you don’t have to pull front cover. Thank you for any help you can give.

Randy Torres

You can buy the Anderson Cam Chain Retention Tool from Anderson Ford Motorsports,, 217/935-2384. You can also purchase a similar tool from Ford; it is called a timing chain wedge tool. Ford also recommends you use its valve spring compressor tool to when changing cams. Any Ford dealer will be able to get these tools for you.