Which cam for better vacuum? 5.0

[Dlachance]

The car is a 95 5.0 with all bolt ons and an f cam. The car has been tuned, but there is a vacuum problem, and when the a/c compressor cycles off, the car dies. What cam(better than stock) should go in? The car has the following mods:

F cam
Lightning heads hogged out
Roller rockers
bbk ssi intake
70mm tb
24#ers
And other minor bolt ons. Sorry if some things sound funny, posted via IPhone.

Thanks guys

[Dacotua]

The car is a 95 5.0 with all bolt ons and an f cam. The car has been tuned, but there is a vacuum problem, and when the a/c compressor cycles off, the car dies. What cam(better than stock) should go in? The car has the following mods:

F cam
Lightning heads hogged out
Roller rockers
bbk ssi intake
70mm tb
24#ers
And other minor bolt ons. Sorry if some things sound funny, posted via IPhone.

Thanks guys

One with little overlap.

[Dlachance]

Is there a particular cam you would recommend?

[mk5.0]

Steeda 19 Is real popular for 94-95

[FoxBodyNick]

xe270hr-12, xe270hr-14 or TFS-1

[turbos66coupe]

I had similar problem with my 95. Tfs intake, bbk headers, x pipe, tune egr delete, stock cam and 1.72rr. I did every thing I could it ran great and no codes but would die on hot starts or when ac cycled. I read around about idle issues with those cars and people drilling holes in tb blades and what not. So created a very small vacume leak jus after tb to simulate this and it never died again and still no codes. Motorsports sells a plate that bolts between the iac that does the same thing but has an adjustable orifice. Its marketed towards 95 cammed cars.

Just my .02

[Dlachance]

I had similar problem with my 95. Tfs intake, bbk headers, x pipe, tune egr delete, stock cam and 1.72rr. I did every thing I could it ran great and no codes but would die on hot starts or when ac cycled. I read around about idle issues with those cars and people drilling holes in tb blades and what not. So created a very small vacume leak jus after tb to simulate this and it never died again and still no codes. Motorsports sells a plate that bolts between the iac that does the same thing but has an adjustable orifice. Its marketed towards 95 cammed cars.

Just my .02

Where exactly did you drill said hole, right before the throttle blade?

[Diabolic]

You need a better tune. Bet I could fix that no problem. My 95 idles @ 800 rpm and never dies. It will lug in a parking lot in 1st gear at 1200 rpm without bucking. My camshaft is larger than yours by quite a bit, and I too have ported GT40 heads. Stock MAF meter? My cam has 238º and .573 lift. My LSA is 112º. Lot easier to tune than to swap a cam. Great blower or nitrous cam you have there.

[Dlachance]

You need a better tune. Bet I could fix that no problem. My 95 idles @ 800 rpm and never dies. It will lug in a parking lot in 1st gear at 1200 rpm without bucking. My camshaft is larger than yours by quite a bit, and I too have ported GT40 heads. Stock MAF meter? My cam has 238º and .573 lift. My LSA is 112º. Lot easier to tune than to swap a cam. Great blower or nitrous cam you have there.

Well the car was tuned not to long ago at Speed-Tek by DFWM username "Prime-Tuning.com"

The F-cam has a 109* lsa if im not mistaken creating a vacuum problem, i may be wrong though. I just want the damn car to run right even if the a/c is cycling on and off. The MAF is not stock, it's a C&L. This car does buck at about 1000 rpm, rolling. The car will never have a blower or nitrous on it, so I am wanting quite a bit smaller cam. I would trade this one for a stock 94-95 cobra cam at this point.

[FoxBodyNick]

F cam is 114

[SEB]

I like the B-Cams, They just sound good & pass emissons & great for Superchargers

[Diabolic]

He's right, the LSA is 114º on the F-Cam. No reason you can't get at least 14-16 inches of vacime at idle. I had to add quite a bit of timing and delay my injector timing to get the idle right. Mine acually likes to run a little lean at idle, about 15.2-15.5 AFR. I acvhieved this by forcing open loop below 1000 rpm. I can target 15.5 AFR and it keeps it there pretty decent. THere is an idle speed adder for AC activation. Perhaps you need to add about 75 rpm or bump the timing a little more. I actually found my target idle AFR and timing by using a vacume gauge. Before tuning my vacume was about 11ish but now it's a solid 15". Brakes work much better too. That cam should be plenty driveable.

Oh, and that C&L isn't doing you any favors. Since you have a tune, might as well go 90mm Lightning or even the stock 70mm would be better. Stock 19# injectors would be fine too. I mean Gen 1 Lightnings come stock with 19# injectors and they have the same heads as you do but with 49 more cubes. I ran 19# injectors safely at stock fp all the way to 325 FWHP. At 350 they were maxed out at the stock fp. You would be doing good to get to 300 at the flywheel with 302 and even ported GT40's.

[Dlachance]

He's right, the LSA is 114º on the F-Cam. No reason you can't get at least 14-16 inches of vacime at idle. I had to add quite a bit of timing and delay my injector timing to get the idle right. Mine acually likes to run a little lean at idle, about 15.2-15.5 AFR. I acvhieved this by forcing open loop below 1000 rpm. I can target 15.5 AFR and it keeps it there pretty decent. THere is an idle speed adder for AC activation. Perhaps you need to add about 75 rpm or bump the timing a little more. I actually found my target idle AFR and timing by using a vacume gauge. Before tuning my vacume was about 11ish but now it's a solid 15". Brakes work much better too. That cam should be plenty driveable.

Oh, and that C&L isn't doing you any favors. Since you have a tune, might as well go 90mm Lightning or even the stock 70mm would be better. Stock 19# injectors would be fine too. I mean Gen 1 Lightnings come stock with 19# injectors and they have the same heads as you do but with 49 more cubes. I ran 19# injectors safely at stock fp all the way to 325 FWHP. At 350 they were maxed out at the stock fp. You would be doing good to get to 300 at the flywheel with 302 and even ported GT40's.

Alrighty, I'll check out the timing and everything else you put in your first paragraph. After getting dyno tuned on Speed-Tek's dyno, it made 287hp/294tq. The timing is set a 10*. Where do you have your timing set?

Thanks for the info!

[Dlachance]

Do you think I may need a new idle control valve?

[Diabolic]

I have my base timing set at 10º as I'm sure yours does as well because of the custom tune. I actually run a total of 29º at idle, but you wont be able to do that unless your tuner makes some changes to your chip. You could experiment by unplugging the spout and advancing the dizzy to 25º on up to 30º and see if that helps with the issue. Imnjector timing will have to be done in the tune as well. Advancing the timing should increase your vacume at idle though. Put a gauge on it to verify. So yoiu make about 315 hp at the flywheel. You could still get away with the 19# squirters and a stock MAF meter. Once you verify what total timing your car likes in order to keep it running with the ac on, call your tuner and ask him to reflash the chip with that amount of timing at idle, add about 75 rpm when the AC is on, and he could also upload the transfer values for a 90mm LMAF meter. Those brand new are less than $100, and are far superior than a C&L.