Yes ,if you have 87 / 88? install s10 head with chevy push rods is a mpg bonanza,use pontiac grand am manifold,, this is cheapest modification to do to 87/88 more horse power, runs better ,better cooling,better mpg parts are cheap at salvage yard,,do not port this head retain header type exhaust with flowmaster or thrush or cherry bomb,a 5 speed can attain 38 to 42 mpg at moderate speeds 26 to 30 around town,econo car mpg,match ports,possible the gasket set will cost what head, manifold and rods cost//// 84 to 86 mild port and match of manifolds, 1 size larger tires,the early dukes need good exhaust header also remember the price of modifications buys a lot of gas,look at miles per gallon improvement for day when gas is $5.oo a gallon or difficult to buy gas I am old enough to remember gas lines,and out of gas cars beside the road,, cheap fixes spark plug electrode alignment.index plugs,engine runs close to perfect air in tires,free flowing exhaust,biggest gas waster in my car is super porker in driver seat with to much foot movement as I down a taco",roller rockers"accurate timing where required,,, 84 to 86 msd coil,not needed on 87/88 ,if you have 84 and you get 32mpg ok,slow down except when teen adrenilene boost needed..KEEP stock air cleaner system ,can remove water separator in inlet,good valve job you can hand lap but stems must be tight..I think that delco rapid fire plugs man have small effect still checking to cheap to buy them my self,,use only cheap spark plugs..many gm cars have problems with bosch platinum,tho my jimmy got 60,000 out of set,tonite at fiero club meeting I was pushed over the edge use ac delco plugs in duke...I have never used ac delco before now I will..The savings is in the cylinder head,normally any increase in mpg benefits engine performance.. all belts should line up straight,NOT simple to do and turn free install 88 5 speed in early model. you can set up transmission as normal 4 speed around town and alter 5th gear to hi overdrive if you spend 50% of time on freeway flying low,but gears are good for normal driving in 5 speed in town do not use all gears sometime you can skip 2nd or 3rd depends on traffic,, driving like the old senile fart I am who scouts for pennies on the ground I rountinely got over 30 mpg in light traffic to work duke will not get good mpg over 70, I,ve tried with fiero that was trouble free for 4 years
[This message has been edited by uhlanstan (edited 10-05-2007).]
