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bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 8:06 pm
by Antwon
hey ive read on a few pages from the states that they have a ls1 running without crank sensor being present I was wondering if anyone has any info or experience with this as I'm in process of converting an old v8 to efi and want the ls1 pcm as I have software to tune it not wanting to run a crank signal as I'm tryin to keep the engine tidy any suggestions or info on this would be much appreciated and I'm not scared to try to flash a custom os or firmware to the pcm if that's the case

thanks in adavnace

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 9:48 pm
by Holden202T
I have seen a front mounted dizzy conversion for LSx I believe it uses a custom timing cover, but I don't really know anything about it, but have seen a few motors with that and carbies.

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 9:57 pm
by HQ355
What v8 are you converting ? Why wouldn't you want to run crank sensor ? It may be easier to run an 808

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 10:33 pm
by Antwon
holden 308 I know its possible to run the ls1 pcm ive seen it done but I mainly want to run it as I have all the software and gear to tune the ls1 pcms, the lt1 ecu in the states only uses the crank as a misfire detection and the engine will still run fine without a crank signal onit but I cant find any info on flashing the lt1 firmware to the ls1 pcm I have thort about trying to do a crank trigger in the dizzy with 12 teeth to get a total of 24x with a full rev of the crank but it wont work I believe as the ecu needs a missing tooth to identify the start of the revolution correct me if I'm wrong tho

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 10:36 pm
by Antwon
and the ls1 pcm offers coil on plug and id kinda like to try and keep that if possible

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 11:01 pm
by HQ355
Have you thought about doing a crank trigger on a 308 ? You can buy the trigger wheels, holden 202t is running similar on his 202

Re: bypassing ls1 crank sensor

Posted: Wed Aug 26, 2015 11:10 pm
by Antwon
hmm. do u have a link or a name of the website to look at for them ive only seen motechs ones but there 12 teeth and theres a us company that make them for sbc that replace the whole timming case but no one has any designed for the 308 as my motor is turboed and spent to much onit to go to a ls1 motor at this stage lol

Re: bypassing ls1 crank sensor

Posted: Thu Aug 27, 2015 8:17 am
by Dylan
VL400 makes an ignition module to run the coil packs with a crank trigger and an 808. Possibly it could be compatible with the LS1 signal? Gee I'd love to see an LS running off an 808.

Re: bypassing ls1 crank sensor

Posted: Thu Aug 27, 2015 9:19 am
by Holden202T
the only way your going to be able to run coil on plug is with some sort of crank trigger with cam signal, dizzy trigger would allow you to run 8 coils but you'll need a home signal to make it work..... as for your 12 teeth in the dizzy, keep in mind the dizzy does one full revolution for 2 crankshaft revolutions, so your 12 teeth will be 6 for one revolution.

my 36-1 trigger wheel works in wasted spark only, to have sequential spark you need the cam sensor so it knows when its back at TDC firing #1.

if you can make a VT V8 dizzy talk to an LSx pcm that will most likely be the easiest solution for you to get everything you need, otherwise you'll need to look at other options.

for crank triggers have a look here http://trigger-wheels.com/store/

Re: bypassing ls1 crank sensor

Posted: Thu Aug 27, 2015 1:05 pm
by Antwon
Thanks. I will look into that i did see one guy make a wheel up with 12 teeth than the gap than 12 teeth again to act as a crank signal thats run off the cam shaft i may look at that option