350 build with LT1 intake and DIS?

[CamaroDude85]

Yeah I priced it out to be something like $2000 for the accessory drive, oil pan, intake, headers, tuning software/pcm and not including the engine price. My Dad has the equipment to do everything but grind cranks so machine work is free for me.

Might have to get with ya about that trigger wheel, this is just all planning in my head right now. Starting a new job tomorrow and hopefully in the next month or so gonna be moving out the ghetto I live in now. I wake up every morning hopping the rims are still on my car, if it wasn't for my dogs they'd probably already be gone lol.

[CamaroDude85]

Got bored and played around with Google Sketch Up some and came up with this. The bolt holes for mounting it to the balancer aren't where they need to be but this is what I'm shooting for the trigger wheel to look like.
NorthStarWheel.jpg

[JeepsAndGuns]

Found a site with some pics of this boat LT1 with the northstar DIS. Would be cool if you could buy the trigger wheel pre made from the boat company.
http://gbodyforum.com/viewtopic.php?...9#.UGzJKJjR7Sg

You can clearly see the plug for the cam sensor simply has no wires to it, and unless I'm looking at it wrong, does it only have one crank sensor?

[EagleMark]

That's an early MEFI ECM, so if someone can hack that bin you'd have all the answers to DIS...

[RobertISaar]

correct me if i'm wrong, but it looks like there is a second sensor above the one that is centered in the picture.

also: i'm not 100% certain WHY the module needs both crank sensors, seeing how almost every other DIS application only used one...

[CamaroDude85]

That marine stuff would make it easier but pricier. I forget the site but they listed the bracket for the sensors for $126!

From what I've read it lets the engine start faster by being able to figure out crankshaft position in 180 degrees of rotation. The link that JeepsAndGuns posted goes into pretty good detail about how the N* setup works. That guy also some good info for brake swaps for the thirdgen. I've seen the "LS1" f-body brakes put on g-bodies S-10's and just about anything else RWD that GM produced with crappy brakes though.

[JeepsAndGuns]

correct me if i'm wrong, but it looks like there is a second sensor above the one that is centered in the picture.

Ya know, now that you pointed it out, it does appear like the 2nd one is up there. I didnt even notice it.

[Six_Shooter]

The pair of crank sensors are needed, has nothing, or at least very little to do with starting in less than 180*, but has everything to do with the ICM knowing where in rotation, the engine is, in other words at what point in the firing order the engine is, while cranking, well and also while running. If you notice the notches, or slits are "randomly" spaced, well, they are not so random, and depending on what each sensor is seeing, being a high (notch in front of a sensor) or a low, no notch) and how many times in a particular amount of time, as compared to the other sensor, will tell the module where in the firing order the engine is. From the theory side, it is supposed to be much more accurate and more responsive to engine speed changes, than the simpler 6+1 trigger wheels used in other common GM DIS systems (60* V6 and older I4).

Alternatively, the ICM can run with one properly spaced crank position sensor and the cam position sensor. If I were to retrofit a N* DIS system, and I plan to, I would start by adding both crank position sensors, then if I felt it was necessary, add the cam position sensor later.

[EagleMark]

This pdf for the MEFI system may help you guys figure it out.

[RobertISaar]

i actually didn't see anything other than the typical dizzy stuff in there.... no DIS references.

[96lt4c4]

I did this a few years back, never finished the project though.

[EagleMark]

I've seen them before but no one mentioned the clearence needed for distributor?

[96lt4c4]

I've seen them before but no one mentioned the clearence needed for distributor?

There was a guy making these with JB weld, pretty rigged up. I was going to run the LT1 heads on the gen 1 SBC, but you have to run the water out the ends of the heads or drill the LT1 intake for water and run a remote thermostat housing, for gen 1 heads. You can only use the small diss. or get more clearence issues. Would have been cool if I finished it I guess.

[icsamerica]

Wouldnt it be possible to run 2 4cyl DIS systems? The 4cyl reluctor wheel is much simpler and each bank would have its own sensor so you would have two crank sensors 180 degress apart. I dont know if the two modules could share a EST signal but it probable would work with an inline diode.

http://www.megamanual.com/ms2/GM_DIS.htm

[Six_Shooter]

Not that simple.

It has been discussed in depth, and due to timing of spark events, spark control events and that the calculations are based the trigger wheel being evenly spaced notches around 360* and not 180*, it would make it very difficult to make work, if it would work that way at all. Keep in mind that much of the math is done internally in the ICM, and the ECM only sees an RPM signal that the ICM generates, based on the signal it gets from the trigger wheel, removing the extra "home" notch.