Rebuilding a SD 5.0 need help

[Phatt_daddy]

I am finally going to rebuild the original 5.0 roller in my 87 gt and I have a couple of questions. First, on a street car that will see some occasional strip time how far out cam you safely bore the block 40 or 60 over? Second, I am using a set of stock E7 heads with a gasket match port job stock upper and lower stock tb and if funds allow a gear 3.55, what is a good cam other that stock that will give me an increase in both power and torque? I know that some have said that it is useless to modify a sd car and that it should just be changed to mass air but I have a very limited budget and I want to get the engine rebuilt first.


Thanks,
Nate

 

[emagdnim]

The nx264 cam I installed made a big difference in power.. low and high! Id recommend a xe270hr-14 from compcams

 

[R2D2]

.030 or .040 over is fine, anymore is useless

 

[foxbody88stang]

IF U USE ANYTHING BUT STOCK CAM THE CAR WILL NEED TUNED OR MAF CONVERTION. SPEED DENSITY CARS RUN HORRABLE W/ MODS AND NO TUNE OR MAF. ITS NOT EXPENSIVE JEGS SELLS A MAF CONVERTION HARNESS $80.00 REMANUFACTURED COMPUTER AUTO ZONE $90.00 FIND MASS AIR METER AT A JUNKYARD OR EBAY CHEAP

I

 

[Daggar]

IF U USE ANYTHING BUT STOCK CAM THE CAR WILL NEED TUNED OR MAF CONVERTION. SPEED DENSITY CARS RUN HORRABLE W/ MODS AND NO TUNE OR MAF. ITS NOT EXPENSIVE JEGS SELLS A MAF CONVERTION HARNESS $80.00 REMANUFACTURED COMPUTER AUTO ZONE $90.00 FIND MASS AIR METER AT A JUNKYARD OR EBAY CHEAP

That is incorrect. There are several off the shelf SD friendly cams out there that run well with the stock SD tune.

 

[emagdnim]

IF U USE ANYTHING BUT STOCK CAM THE CAR WILL NEED TUNED OR MAF CONVERTION. SPEED DENSITY CARS RUN HORRABLE W/ MODS AND NO TUNE OR MAF. ITS NOT EXPENSIVE JEGS SELLS A MAF CONVERTION HARNESS $80.00 REMANUFACTURED COMPUTER AUTO ZONE $90.00 FIND MASS AIR METER AT A JUNKYARD OR EBAY CHEAP

I

LOL @ the caps .. Tons of people run non-stock cams , intakes, and even heads fine with SD.

 

[stang&2Birds]

IF U USE ANYTHING BUT STOCK CAM THE CAR WILL NEED TUNED OR MAF CONVERTION. SPEED DENSITY CARS RUN HORRABLE W/ MODS AND NO TUNE OR MAF. ITS NOT EXPENSIVE JEGS SELLS A MAF CONVERTION HARNESS $80.00 REMANUFACTURED COMPUTER AUTO ZONE $90.00 FIND MASS AIR METER AT A JUNKYARD OR EBAY CHEAP

I

Ha, ha - newbie. Can't spell and is using a TELETYPE, WITH ONLY CAPS, FROM THE 50's.

For SD, the vacuum at the different load points is very important. Like Dagger said, there are a few SD friendly cams out there.

To *greatly simplify*, the EEC uses the rpms and vacuum to determines "engine load". Then, that "load" is used along with other parameters to calculate the fuel requirements. With different cams, the vacuum is different at different load points. It a matter of "how much" different, the percentage that different makes in the base calculations, and how much the EEC cam adjust it's different "trim/fine tune" values.

A number of people have use the FRPP "smog legal" cam on SD stangs. Use those lifts and durations and *overlap* as a base-line. Then, get a good dual pattern cam with similar specs. Be very careful of the overlap! That's what changes the vacuum level at different loads very quickly (compared to stock).

Going to a radical cam, or bigger injectors without a chip or Tweecer is "possible", but IMHO, only EXPERT SD people should even try it.

If you want a bigger cam and/or injectors with SD, go to a DA1, and get a Tweecer so you can tune the EEC. A Tweecer is ~$500 and takes ~20 to 40 HOURS to "learn".