Distributor ????

[Spoonbill]

I have an 87 r10 305 tbi 700r4. I have a question about the distributor. I don't have the typical hei distributor cap. It has an external coil and a very funky cap that I have never seen on any other vehicle. The cap isn't round. One side of it it flat and their is an indentation on the bottom of that side of the cap like for a wire plugin or something. What I was wondering was could I put a conventional hei distributor in there?? Any help would be great. Thanks

[VileZambonie]

No, you have the correct distributor for your tbi system.

[Stewart G Griffin]

1) Why do you want to switch to a regular HEI?

2) i think you can do it, but it may not be compatible with the TBI system right off the bat without doing anything.  TBI needs to see, at the very least, RPM, i think?
There are ways to make it work beyond just stabbing the distributor in there.

Plus, if the engine has a roller cam, then you have to install special (melonized) distributor gear or the cam will eat the dist gear up fast and the cam gear may be damaged as well.

[Spoonbill]

Nothing wrong with mine style but I just really like the hei setup. The worse thing about mine is that it extremely difficult to get the cap back on beacause of that open spot where the wires come in. It can literally take hours just on that alone. When I did a tune up on it a few months ago and I couldn't get it on so I thought, bad cap right. Nope, they were all like that. Hei setups are easy as pie and they perform flawlessly. What direction would you go?

[bd]

Nothing wrong with mine style but I just really like the hei setup. The worse thing about mine is that it extremely difficult to get the cap back on beacause of that open spot where the wires come in. It can literally take hours just on that alone. When I did a tune up on it a few months ago and I couldn't get it on so I thought, bad cap right. Nope, they were all like that. Hei setups are easy as pie and they perform flawlessly. What direction would you go?

Replace only the parts that need to be replaced.  The distributor in your R10 is HEI.  Replacing the cap in a TBI truck is a snap!  Just align the window in the cap with the dust grooves in the module bulkhead connector.

[VileZambonie]

I don't understand how it could take hours? My ignition module blew a few weeks ago and I had it swapped in 10 minutes. All you need to do is put the cap in the groove on the module and it will be aligned. 2 screws hold it on and that's about it. Sounds like you had it crooked or something.

[Spoonbill]

I know guys, if I hadn't seen it myself I wouldn't have believed it. It took me almost 3 hours just to get the cap on. The screws are so tiny you can barely hold them but I don't think that is it, I'm thinkin the holes weren't drilled right cause you can get one in but not the other and then wham, just like that they were both in. I don't understand it at all

[Spoonbill]

Zambonie. What the heck is that module that you put in the pic. I've never seen that before

[Spoonbill]

Anyone else know what the module in zambonie's pic is???

[bd]

That is an HEI ignition module from a TBI distributor (image).  The red cap in the image improves contrast to help you discern the module as separate from the cap.

[Spoonbill]

Yes, that is exactly the distributor I have and I do not like it at all. Do I at anytime need to replace the hei ignition module?

[VileZambonie]

Sounds like it doesn't like you either 

When it fails you do.