Oh you could most definitely just use junkyard LS coils. You'd need both the coils and their stock harness which you would adapt into the new ECU's harness. I'm not sure how much of an extra benefit the smart coils are over stock LS coils, it just makes more sense to me if I'm going with an all out standalone ECU install to get "upgraded" coils that supposedly have more features than some junkyard coils. Some of the things I do know before doing any real research on the smart coils is that the kit they come in uses 12 gauge wire for their power source, and with the new ECU you can do more aggressive timing ramps, as well as individual cylinder timing control.

That would require modifying the stock valve covers to accept the coils since you can't swap to some LS valve covers. Also for looks, like you said. I don't like the look of the coils on the valve covers. I'd prefer to probably mount them to the front of the strut tower brace.

Since that's a kit for a V8 you can save 110$ by buying the wiring and 6 coils separately

 

Thanks so much for replying. It means a lot for the veterans of the forum and 3800 platform, to keep helping me out through my build. It was just a coincidence I got into this platform honestly. I saw the car for sale near by, bought it for 1500$, drove it my last year of high school, and been trying to go faster ever since. As far as the tranny suggestions you had, I'm not sure if you've seen my other threads, or know anything about my build plans. I'm slowly working my way towards an all out turbo car, with a 4T80e swap. I assume you're still running the 4T65e, hence the very pricey diff and rebuilds. Brandon Furches started a brand/shop by the name of LS4 King. The main specs on his 6th gen monte are large turbo LS4, stock 4T80e, about 800hp. So the issue of the trans holding together should be solved for my build, as I plan on making 600-800hp.

I'd love to see that parts list if you don't mind. Also a couple questions regarding your build. What cam do you have in your monte? And how are cold starts with the dominator? Does the engine crank and then go up to 1300-1500 like a stock ecu, or does it crank and stay at idle rpm?

 

Wow, I had no idea they were anywhere near that expensive. No offense intended, but I don't think I could justify that kind of money without some huge power gain to go along with it. I don't think I've got that much in my whole engine build at this point.


How's the traction control / boost by speed-gear? Are you able to just flat out floor it and let the computer handle the rest?

 

It is extremely expensive. The wiring really adds up quick. But we are talking about top of the line engine management from a major EFI company. This ECU is used on pro mod cars.

I've done some more research on the ignition side of wiring this thing up. To use the stock coils and bypass the stock ICM, you might be able to use part number 554-112, which is a four channel 2 wire coil driver. I say "might be able to use", because I'm not sure how only using three out of the four drivers would go. Since it's a four coil driver, you'd need two, but only run three of the four coils per driver. But I wouldn't go that route though. Upgrading to LS style smart coils is just a wiring harness. Stock LS smart coils, and all the aftermarket smart coils like Holley, MSD, etc., are plug and play. I also shot Holley support an email to see if the ECUs are compatible with stock 3800 cam and crank sensors. It'll probably be a while before I hear back though, considering Thanksgiving is tomorrow.

 

Even $550 for that setup is still way higher than stock LS stuff. Thats probably 5x what you could get stock LS stuff for at a junkyard, and probably nearly double buying new coils + bare harness connectors + wires depending which coils you went with.

I get wanting a strong ignition, I'm just not sure you're going to have tangible gains with something notably stronger than stock LS given they've been pushed to power levels way beyond what any 3800 ever has, even when adjusted to a hp / cyl basis.

Certainly not trying to say its not an excellent setup. I just question the cost / benefits ratio on this platform. What finacially makes sense on a $50-100k pro mod engine doesn't necessarily on a $5-10k 3800 engine that's barely going to make 1/4 of the power.

The other thing is that the stock 3800 pcm has proven to be sufficient to handle pretty big power - well over 600 whp, so I'm not really sure what extra this allows you to do at the power limits we're dealing with on this engine architecture. If the traction control / boost by speed was flawless, that would certainly be a big bonus for a serious racer, but I don't see any 3800 being competitive enough in today's world to make that feature alone worth the huge price of admission.

Just my .02 - not at all trying to put down Greg's build.

 

Thanks so much for the info on your car, and the kind words.

The cam you've got is definitely a custom grind. Comp Cams has three cams for the 3800, two NA, and one blower. (part numbers for those cams if anyone's interested: 76-800-9, 76-801-9, and 76-802-9) But none of them are rated to make power past 5500rpm. ZZP's discontinued ST1 cam was rated to make power up to 6000rpm, so I'm hoping the ST4, which is the cam I've got in mind for my build, will make power a bit higher than that. I'm thinking about shifting between 6800-7200 rpm.

Questions:
If you're still using the factory dash, how many of the gauges still work? Were there workarounds you had to do to get them to still work?
Are you still running factory fuel rails?
Do you know what your torque converter stall is?

 

I've still been doing research on this topic cause I was unsure of the compatibility of the stock cam/crank sensors with the Holley ECUs. I made a thread on the Holley Forum asking about it, since I haven't received a reply from Holley's support team. A forum user there posted a reply linking this thread "HP EFI On 3800 V6 Engine". This thread has all the info needed to set up the Holley software using the stock cam/crank sensors, and LS style smart coils. It basically boils down to changing the firing order to get the cam/crank timing where it needs to be, using a 3x crank/1x cam type setup, and a couple other settings. The 3x crank is accomplished by only using one of the two crank sensor signal outputs. Which means the 18 tooth reluctor on the back of the balancer isn't used, only the 3x ring and it's output is used. This setup also allows the use of LS style smart coils, and the bypassing of the stock ICM.

 

TBH, I didn't read the entire thread as its pretty huge, but isn't changing the firing order of the engine a really serious modification (at least a new cam, maybe even new crank + cam depending on what all is getting moved around)?

 

I did read through the whole thread, cause I wanted to make sure I didn't miss any important info. I feel like I have to say that I'm very new to timing engines. I never learned the old ways of setting timing like with a SBC. So I may be missing a piece of the puzzle. But as I understand that thread I linked, there are no engine modifications to be made. The reason the firing order is changed is to get the cam sensor in the right position during the timing events for the Holley software to run the engine correctly.

 

I contacted the OP of that thread directly and he confirmed what I thought. There is no mechanical changes done to the engine. Everything stays where it was with the factory ECU. The change in firing order is used to get the cam signal "lined up" properly with the crank signal.