Motor Rebuild

Hopefully this is the right place for this. I am basically looking for some knowledge about what to do with my motor, as I don't have a lot of knowledge in this area. I have a 1988 Mustang GT, and I plan on cleaning up the bottom end and leaving it stock other than some new rings. I am looking at getting some GT 40 heads, here is what I would like to know more about. What can be done to the heads, to improve their performance? Can a simple port job be a worthwhile investment without rebuilding the rest of the head ie; stock valves and springs? Also I hear talk of 1.7, and 1.6 ratio rockers. What does this mean? Also I was wondering if there is a Speed Density friendly cam that would work well with a set of GT 40 heads, and also whether I would benefit from an after market intake or whether the explorer intake would work best.

Thanks for helping to build up my knowledge on this subject.
 
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You should invest in a couple good engine building/rebuilding books before you ever crack that engine open.

Depending on budget, why not look into an aftermarket set of aluminum heads?

As far as the intake, the Explorer = Cobra = Tubular GT-40. The Explorer is a decent intake that can support some decent power if matched with a good combo.

Rocker arms are defined in terms of how much they multiply the actual cam lobe lift. A 1.6 rocker increases cam lift 160% at the valve, and a 1.7 increases it 170%. SO, if a cam lobe measures .300" lift, when equipping it with 1.6 rockers, actual valve lift would be .480". With a 1.7, you're looking at 0.510". That makes it sound like you'd always want to use 1.7s over 1.6s, but the reality is you have to take into consideration the cam grind, valve springs, etc. to determine what s best for the combo.

Lastly, I would just convert to MAF and be done with it.
 
I have gt40 heads and an edelbrock intake and its still speed density. The stock cam is a great piece and works great for basic builds.

The thing with gt40 (cobra/explorer heads) is that they arent worth porting. They are an entry level street head that is cheap and will give a noticable improvement over stock E7 heads. There are people that have squeezed close to 300hp out of explorer head/intake combos but the majority fall around the 250-260rwhp mark. That is still 80hp over stock. Not bad for a combo that can easily be purchased for less than $400.00
Port work after considering the base price of the head along with new valves can easily run into the 7-800 dollar range. At this point I would highly suggest considering aluminum heads. They are lighter, dissipate heat better, out of the box outflow nearly every iron head on the market. Usded aluminums can be had for under 1000 dollars and will flow right there with ported gt40 heads.
 
I have gt40 heads and an edelbrock intake and its still speed density. The stock cam is a great piece and works great for basic builds.

The thing with gt40 (cobra/explorer heads) is that they arent worth porting. They are an entry level street head that is cheap and will give a noticable improvement over stock E7 heads. There are people that have squeezed close to 300hp out of explorer head/intake combos but the majority fall around the 250-260rwhp mark. That is still 80hp over stock. Not bad for a combo that can easily be purchased for less than $400.00
Port work after considering the base price of the head along with new valves can easily run into the 7-800 dollar range. At this point I would highly suggest considering aluminum heads. They are lighter, dissipate heat better, out of the box outflow nearly every iron head on the market. Usded aluminums can be had for under 1000 dollars and will flow right there with ported gt40 heads.

Do the GT40 heads have the smog hump in the exhaust ports like the E7s? At the very least, that would be worth grinding away, right?
 
IF YOUR LOOKING FOR A GOOD HEAD WITH A GOOD PRICE GO TO TRI STATE CYLINDER HEAD.COM 798.00 FOR A SET OF 5.0X HEADS WITH BOLT DOWN ROCKERS OR STUD MOUNT ROCKERS. I HAVE A FRIEND THAT HAS A SET AND WE COMPARED THEM TO SOME GT-40X HEADS THEY LOOK THE SAME, VALVES AND PORTS MEASURE OUT THE SAME.

AS FAR AS AN ENGINE REBUILD YOU CANT GO WRONG WITH SUMMIT ENGINE KIT. MAKE SURE YOU HAVE THE CRANK TURNED A YOU LOCAL MACHINE SHOP TO CHECK FOR BEING OUT OF ROUND,AND RODS UNLESS YOU AR GETTING NEW ONES, AND YOU CAN HAVE THEM GET YOUR BEARINGS TO MATCH ALSO.

INTAKES I AGREE WITH THE OTHER GUYS ABOVE COBRA, GT-40, EXPLORER

HOPE THIS HELPS.:nice: