i have a 1988 318 that i swap in my truck and i was wondering if anyone knows if it is ok to use my v6 wiring harness...........the motor is a 318 tbi, i think i have A500 but it might 904 or 999 how can i find that out.

 

Still no luck on the harness huh? Tell you what,since the V-6 is basically 3/4 of a 318, if everything will physically plug in, give it a shot. Obviously you'll want to use the 318 dist. and computer.

 

yeah no luck, this is really stressing me out. another question how can i find out what transmission i have is it A500 or a 904 or 999

 

A-500 is an overdrive version of the 904. The 999 is also a version of the 904. Look at the pan, if there's a bulge on one corner, your in luck, 727,or 518 OD. No bulge, small trans. With your truck being a V-6, 99.5% chanceit's a little 'un. As long as you don't abuse it, [any,no neutral drops, no backing up slamming it in low] it'll be fine. But while these trans. are pretty weak in stock form, can be beefed to take a lot of HP. Expensive though.

On the harness, if it'll reach,and will plug in, I'd give it a shot. If a sensor is a little different on the plug, swap it for the V-6 sensor. Most of these sensors all read about the same resistance. Whaddya got to lose? [Other than your sanity?]

Let me give you a short version of the system. The dist. has a shutter wheel and pick up inside. A V-6 has 6 windows in the wheel, V-8s 8. This generates a signal for the computer, which fires the coil, and pulses the injectors. The computer reads varous inputs, vacuum, ex. oxygen content, temp, throttle position, RPM, and calculates the fuel and timing accordingly. If it weren't for the pre programmed timing curve, and idle speed parameters, you could run the 318 with the V-6 computer! Unfortunately, the extra winows in the shutter wheel make the computer think the motor is running faster than it is. Throws the timing curve etc into a cocked hat. While it would start and run, it wouldn't run right. The 318 computer is the only fix. Maybe this will help you understand the system a little better. Once you get the hang of it, it's a simple system.

 

man thanks! i know my tranmission is not 727 (i wish) its ether a A500 or 904 or 999 because my pan shape.... on the shift all it says is [R N D 2 1] i dont know if it has O.D. my truck is a 1988 D-100 1/2 ton 3.9 TBI, how hard would it be to put a A727 in it?

 

No OD button on the dash? The linkages are the same, different drive shaft and yoke. Possibly different cooler line fittings. Nuetral balance converter. No weights. No biggie. My '88 has a 904/318. Trans is trashed. Apparently used to pull a heavy trailer before I bought it. Only gave $200 so no big loss. Ran good, robbed the TBI off of it, Sure Grip rear end etc.

 

Unless you plan on big horepower,racing or towing heavy loads,the 904/999 propperly maintained will be ok.
The 727 will handle more but also uses more horepower to operate.

 

yeah i dont have a O.D. button.... so i might have 904 then and the 727 is for big HP engines ok....hey thanks lugnuts and moparborn