Injector basics for LSJ
#27
I agree with you 100%. But there is no way you can argue that a split spray pattern injector is the best choice for a 4 valve motor such as the LSJ. While you can make the other injectors work well, imagine how much better it would behave with that same injector but split spray.
The Siemens/Motron are a dual negative; poor spray pattern AND atomization.
The ID's just spray so fine that they do alright. That same atomization in a split cone would be awesome.
The thing I've found is most large injectors are a tight angle, leads one to assume that it's easier to achieve a good compromise between volume and accuracy.
#36
tunning or (A tune)
yes im a newbie. yes i want to make My stock ( no boost ) LS as fast as i can. I seeing the word Tune Comming into play here. Im new to tuneing and trying to make these cars faster. Is there something that you do your selves to tune the car or are you all taking it to the shop. are there chips that change the tune of the car. and what are some things you all doing besides the obvious TURBO\Supercharger. that are giving these cars a little ass.
and how the hell can you get the governor off. she shuts down at about 105. can you adjust that some how. I was runing a balt this morning and we were running along pretty good he was slowly pulling on me and then my governor kicked in and he was still going. I dont know what he had all the emblems were taking off the car. as the previous owners did with mine.
thanks
and how the hell can you get the governor off. she shuts down at about 105. can you adjust that some how. I was runing a balt this morning and we were running along pretty good he was slowly pulling on me and then my governor kicked in and he was still going. I dont know what he had all the emblems were taking off the car. as the previous owners did with mine.
thanks
#39
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Not that I am any help, but these injectors sound good to me, and I'd like to see this topic achieve some resolution, so I'm mostly just bumping TTT
from what I gathered from this thread and the one on HPT forum, Fuel Injector Connection has offset tables to go with the injectors, based on the OP's work.
the specific questions I have regarding use of these injectors vs. the rest of the tune, are:
whether the offset values get entered as -is or halved,
whether the stoich gets entered proper, or doubled,
and whether the IFR gets entered as 60 with no multiplier, 63.5 with a multiplier to bring it to 72, or some other value I missed in the two applicable threads.
what DO know is; I have mototron 80's and my car idles like crap. I believe I STILL don't have proper injector data. I'd love to get a great set of injectors with proper data, and finally get a decent baseline for a decent tune
from what I gathered from this thread and the one on HPT forum, Fuel Injector Connection has offset tables to go with the injectors, based on the OP's work.
the specific questions I have regarding use of these injectors vs. the rest of the tune, are:
whether the offset values get entered as -is or halved,
whether the stoich gets entered proper, or doubled,
and whether the IFR gets entered as 60 with no multiplier, 63.5 with a multiplier to bring it to 72, or some other value I missed in the two applicable threads.
what DO know is; I have mototron 80's and my car idles like crap. I believe I STILL don't have proper injector data. I'd love to get a great set of injectors with proper data, and finally get a decent baseline for a decent tune
#40
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If the info is out there, can we put some solid facts about Injector offset halving, working or non-working voltage multiplier etc. in this thread??
I have the same Bosch injectors in my Harrop-ed LSJ (super unleaded), but I'm using these in a return style sytem together with a Saab 3.0 bar regulator. That keeps my injector value just under the 63lb limit for all fields, so I don't have to dick around with multipliers...
Runs and idles pretty good, also with the ZZP Stage 2 cams.
#41
The voltage multiplier does not work over 63.5
For example if you have an ifr of 50 and a multiplier or 2.0, it still caps at 63.5, not 100. Scaling needs to either be done through maf/ve or stoich.
I have verified this myself. 115# injectirs, ifr at 63.5 flat in the table (boost ref), multiplier of 1. I can change the multiplier to 2.0 and absolutely nothing changes. Not cranking, trims, or wot. Nothing. If that table worked over 63.5, my car would not have even ran when I changed it to 2, because it would have been only getting half the fuel.
As far as the offsets go, I have not taken the time to play with halving them and dialing them in. Tuning in offsets is a very time consuming process.
I have the injector data created by the op I need to dig up for spawnee and anyone else that wants it.
Take note though that this is his data, not mine, and he does not have it scaled properly.
For example if you have an ifr of 50 and a multiplier or 2.0, it still caps at 63.5, not 100. Scaling needs to either be done through maf/ve or stoich.
I have verified this myself. 115# injectirs, ifr at 63.5 flat in the table (boost ref), multiplier of 1. I can change the multiplier to 2.0 and absolutely nothing changes. Not cranking, trims, or wot. Nothing. If that table worked over 63.5, my car would not have even ran when I changed it to 2, because it would have been only getting half the fuel.
As far as the offsets go, I have not taken the time to play with halving them and dialing them in. Tuning in offsets is a very time consuming process.
I have the injector data created by the op I need to dig up for spawnee and anyone else that wants it.
Take note though that this is his data, not mine, and he does not have it scaled properly.
#43
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The voltage multiplier does not work over 63.5
For example if you have an ifr of 50 and a multiplier or 2.0, it still caps at 63.5, not 100. Scaling needs to either be done through maf/ve or stoich.
I have verified this myself. 115# injectirs, ifr at 63.5 flat in the table (boost ref), multiplier of 1. I can change the multiplier to 2.0 and absolutely nothing changes. Not cranking, trims, or wot. Nothing. If that table worked over 63.5, my car would not have even ran when I changed it to 2, because it would have been only getting half the fuel.
For example if you have an ifr of 50 and a multiplier or 2.0, it still caps at 63.5, not 100. Scaling needs to either be done through maf/ve or stoich.
I have verified this myself. 115# injectirs, ifr at 63.5 flat in the table (boost ref), multiplier of 1. I can change the multiplier to 2.0 and absolutely nothing changes. Not cranking, trims, or wot. Nothing. If that table worked over 63.5, my car would not have even ran when I changed it to 2, because it would have been only getting half the fuel.
the Mototron 80's in my car -- ZZP says they're rated at 89 lb/hr @ 43.5 psi, which translates to 102.77 lb/hr @ 58psi (stock fuel pressure in our LSJ's)
since 63.5 is the max, and the multiplier doesn't work, we enter 63.5 in every cell of the IFR table for a boost referenced system
then something else has to make up the change -- 102.77 divided by 63.5 = 1.618
so we could change the stoich by 1.618 --- 14.7 divided by 1.618 = 9.08, and then tune the MAF and VE tables normally
OR
leave the stoich as is and scale the MAF and VE tables by the same 1.618, and then tune them as normal
that sound correct ?
#44
so if I understand this correctly;
the Mototron 80's in my car -- ZZP says they're rated at 89 lb/hr @ 43.5 psi, which translates to 102.77 lb/hr @ 58psi (stock fuel pressure in our LSJ's)
since 63.5 is the max, and the multiplier doesn't work, we enter 63.5 in every cell of the IFR table for a boost referenced system
then something else has to make up the change -- 102.77 divided by 63.5 = 1.618
so we could change the stoich by 1.618 --- 14.7 divided by 1.618 = 9.08, and then tune the MAF and VE tables normally
OR
leave the stoich as is and scale the MAF and VE tables by the same 1.618, and then tune them as normal
that sound correct ?
the Mototron 80's in my car -- ZZP says they're rated at 89 lb/hr @ 43.5 psi, which translates to 102.77 lb/hr @ 58psi (stock fuel pressure in our LSJ's)
since 63.5 is the max, and the multiplier doesn't work, we enter 63.5 in every cell of the IFR table for a boost referenced system
then something else has to make up the change -- 102.77 divided by 63.5 = 1.618
so we could change the stoich by 1.618 --- 14.7 divided by 1.618 = 9.08, and then tune the MAF and VE tables normally
OR
leave the stoich as is and scale the MAF and VE tables by the same 1.618, and then tune them as normal
that sound correct ?
If starting with a stock tune the
#45
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If its gonna be a nightmare trying to dial in these injectors because of a lack of HPT data I wont even bother, I would presume that ZZP has the bosch green giant #42's pretty well mapped out for HPT (i would hope) so if thats a better alternative Ill just go that route. I was going to stick with the LSJ injectors but everyone is saying once you go off the stock pulley they are useless, despite already having the fuel pump rewire which gave me about a 10% bump in fueling on the MAF table. Probably wont be enough for a 2.9 pulley.
#47
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[/QUOTE] You went the wrong way on stoich, but you have the right idea. But, it's MUCH easier and equally as effective to simply use a factor of 2. As in cut the ifr values for the specific injector in half (assuming they're smaller than 127#), and either double stoich or cut maf/ve in half and fine tune. I tried the stoich method and had cranking fuel issues, so I simply reverted back to the scaled airflow. The only catch is any table that uses airflow as an axis needs rescaled also, but that's pretty simple.
[/QUOTE]
now I'm tempted to try this with my current injectors, before giving up and getting the 60's that started the thread. I have 2 or 3 different offset tables for 80's, I wonder which ones are "right" ?
Last edited by wayfarer; 12-21-2014 at 11:33 AM.
#50
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I do not know about his offsets. Like I said I have not played with them; I just have the file he originally supplied. The only thing I know for sure is that in his file he uses the voltage multiplier, which doesn't work.
You went the wrong way on stoich, but you have the right idea. But, it's MUCH easier and equally as effective to simply use a factor of 2. As in cut the ifr values for the specific injector in half (assuming they're smaller than 127#), and either double stoich or cut maf/ve in half and fine tune. I tried the stoich method and had cranking fuel issues, so I simply reverted back to the scaled airflow. The only catch is any table that uses airflow as an axis needs rescaled also, but that's pretty simple.
If starting with a stock tune the
You went the wrong way on stoich, but you have the right idea. But, it's MUCH easier and equally as effective to simply use a factor of 2. As in cut the ifr values for the specific injector in half (assuming they're smaller than 127#), and either double stoich or cut maf/ve in half and fine tune. I tried the stoich method and had cranking fuel issues, so I simply reverted back to the scaled airflow. The only catch is any table that uses airflow as an axis needs rescaled also, but that's pretty simple.
If starting with a stock tune the
That's the tricky one, as by scaling the MAF & VE table your ecm "sees" less airflow than there actually is! And this affects f.i. the ignition table that is based on measured airflow... There is a good write-up somewhere how to properly scale GM tunes. But then the problem arises that HPT does not give access to all LSJ tables and some of these should be altered for a proper scaled tune.
So that's why I changed my fuel regulator for a 3.0 bar Saab version and I don't have to scale anything for these Bosch injectors.
And my idle and transient behaviour is pretty good with these.