anthros

will the 1985 mustang gt's engine acept a x303 camshaft? i'am just curious as to if the block is compatable with the cam and roller lifters, if the stock block is not compatable with it, is there anything i can do to make it accept the x303 camshaft and roller lifters?

aode08

no it will not


your pistons are not notched. you will need a .030 head shim on both heads

86HOGT

Ahem, your block should be roller and your pistons should have some sort of valve reliefs but always check your PTV clearance. The 86s were the only true flats tops.

5IVE.OH

I hope your not running that in a stock motor.

Joel5.0

As 86HOGT mentioned.....if the engine is an '85, and not from an '85 auto GT (these were non-roller)....it will "accept" the X-303 cam. If you plan on using it with the stock heads....very, very little gains should be expected (if any)....the X-303 is basically a B-303 cam with more lift, you should check PtV to confirm clearance, degree the cam, and install it 4° advanced based on the results of the cam degreeing. My 2¢.

P Zero

Whats the lift on the X303? 85's should be 4 "brow" pistons. And if youre using the stock head a B cam would be better, cuz the stock heads cant flow enough for a larger cam.

Joel wtf you talkin bout, he'll have HUGE gains over the stock cam. The stock cam is tiny in comparison.

Anthros, is your car stick or auto?

One more thing, as far as I know even the auto's had roller motors, they were rquipped with CFI rather than the holley/motorcraft carbs on the 5-speeds.
-P.

FutBall23

`1
hes talkin about having to big a cam for a stock motor, just try it if you have a stock motor and see

hellas85stang

my85 gt auto with a aod was a roller block...and was the orig motor,,,

Joel5.0

CFI Auto GT's were not roller blocks, they were the exception. Lift on the X-303 is .542" w/1.6 rockers...timing events are the same as the B-303...again, total lift is not an issue with PtV, and since both (B&X) have an overlap of 0° @.050"...........

X-303 "power" doesn't come into play until 2800-3000 rpms....+another item that would need to be taken care of, is the upgrade of the valve springs for either one. The stock cam might be "tiny" by comparison, but if the heads are left intact......they become the bottleneck. When you mention HUGE, do you mean 25-35HP?....check http://www.jason.fletcher.net/tech/cams/cams.htm + I'm an X-303 cam user myself.....

FoxGT

.542/.542 lift on it. It won't work on the 85 I know for a fact because of the pistons, friend tried it on his & it got close, he ended up not using it. I guess, technically he didn't try it, got scared & didn't want to risk it. I also know for a fact it will work in an 87-93. I have one in my '89 GT.

Edit: looks like he beat me to it [8D]

+1 on the power coming in. You can definetly notice it. Starts to pull alot harder around 2600rpm for me.