Too much timing?
03-15-2016, 08:36 PM
#42
and to the original question, my very similar setup blew itself up big time with a tune with not much more peak timing. but every setup is different and I'd imagine the dynamic compression based on the cam is totally different for each car is all over the map. I'm not tuner and most of the guys in here have a lot more experience than I do with FI vettes but if it were me I'd pull the timing down a touch for peace of mind but just my $0.02
03-16-2016, 01:30 PM
#43
Burning Brakes
03-16-2016, 04:10 PM
#44
exactly, there have been other threads too that had this topic discussed within at some length. This dynamic has been reported and measured by more people than just doug at ECS too.
when I spoke to Julio at Alky control he also said that he always recommend putting the methanol nozzle as far away from the throttle body and as close to intercooler exit as possible and that he's seen this uneven cylinder flow be much worse with meth nozzles right at the throttle body.
I bet the 300* EGT temp differences are probably not tragic on the street or maybe even 1/4 mile runs but I'd bet at 1/2 and standing mile events could be why a lot of guys blowing stuff up. FWIW when my last ls2 blew up from horrible tuner with far too much timing it lost the front passenger cylinder and I had dual M15 tips on it at the time. I remember being surprised at the time thinking weird for it to not blow up #7 but makes sense now.
when I spoke to Julio at Alky control he also said that he always recommend putting the methanol nozzle as far away from the throttle body and as close to intercooler exit as possible and that he's seen this uneven cylinder flow be much worse with meth nozzles right at the throttle body.
I bet the 300* EGT temp differences are probably not tragic on the street or maybe even 1/4 mile runs but I'd bet at 1/2 and standing mile events could be why a lot of guys blowing stuff up. FWIW when my last ls2 blew up from horrible tuner with far too much timing it lost the front passenger cylinder and I had dual M15 tips on it at the time. I remember being surprised at the time thinking weird for it to not blow up #7 but makes sense now.
Last edited by neverstop; 03-16-2016 at 04:16 PM.
03-23-2016, 03:36 PM
#45
Said it before, I'll say it again. It has less to do with the timing and more to do with meth and how it gets used.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
03-23-2016, 04:28 PM
#46
Said it before, I'll say it again. It has less to do with the timing and more to do with meth and how it gets used.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
Direct port meth injection is a pretty simple solution. 3GPH nozzle in each intake runner will get it done!
03-23-2016, 05:31 PM
#47
Melting Slicks
Said it before, I'll say it again. It has less to do with the timing and more to do with meth and how it gets used.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
Boosted C5/C6 logic = shotgun a bunch of meth into your charge pipe and then blame everything else but the meth when the motor blows because "everyone is doing it"
Meth sucks. It's good for making more power than pump gas alone allows but you will always be rolling the dice because of UNEQUAL CYLINDER DISTRIBUTION. Nobody wants to ever talk about this, it gets brought up every now and then but the topic never gets any traction.
Just because some well respected members on here are running triple nozzles of meth doesn't mean it's smart or the best way. Meth will never be able to touch what E85 (or race gas) can do for you.
Where is the line draw on how much is too much and starts to become issue. Is 2 10 gph nozzles efficient then beyond that gets messy?
Is the solution to run a carb style intake and maybe that distributes meth better?
Problem is I cant readily get E85 at a pump and its not easy to put flex fuel in a C5 anyways. Which leaves having a drum of race or E85 so meth and pump becomes much more convient.
Not expecting you to have all the answers really just thinking outloud.
03-23-2016, 06:14 PM
#48
Melting Slicks
Where are the screenshots of datalogs to support the claims of a delta between the front and rear cylinders? The airflow has to take the same path for each of the cylinders. There isn't an extra turn thrown in there for the front cylinders.
03-23-2016, 06:20 PM
#49
Melting Slicks
That's a bold statement. Are we talking meth injection or meth as the sole fuel source. Anyone making 2500hp on E85?
03-24-2016, 01:07 AM
#50
Maybe spend less time splitting hairs and more time learning how to keep your car running
03-24-2016, 01:11 AM
#51
LSx platform is amazing for making power, but we are severely limited by our PCMs, and some of the standalone systems really aren't that great while the ones that are are way too expensive for me to afford.
That's why I moved to a different platform (N54). Yeah we aren't making as much power yet but tuning/development is more fun.
03-24-2016, 01:36 PM
#52
Melting Slicks
Deductive example:
- Corvette Forum claims that all corvettes with 800 rwhp run 9s in the quarter.
- Milan's corvette has 900 rwhp.
Conclusion: Milan's corvette runs 9s in the quarter.
This example although valid is not sound. Your corvette has yet to produce a 9 second timeslip and video.
Milan's Inductive example:
- I have tested meth distribution on vehicles that have the ability to log individual cylinders.
- The corvette platform isn't magically different from these other vehicles.
Milan's Conclusion: The C5 corvette has UNEQUAL CYLINDER DISTRIBUTION.
You took a specific case and then made a general statement without a guarantee or facts to support the claim.
03-24-2016, 01:46 PM
#53
Doug and I believe Vengeance also only run up to dual M10 tips and I believe that is the biggest they go.
03-24-2016, 05:03 PM
#54
Melting Slicks
Look at this picture and explain how the air flow path is different (sharper) between the cylinders. The air flows along the bottom floor of the intake and the angle of approach is almost identical for each port. Same runner length, same turning radius, what is different?
03-25-2016, 07:55 AM
#55
Le Mans Master
Look at this picture and explain how the air flow path is different (sharper) between the cylinders. The air flows along the bottom floor of the intake and the angle of approach is almost identical for each port. Same runner length, same turning radius, what is different?
I see way more variance on plugs from the left bank to the right bank then front to rear.
I'd like to know why #5 and 7 are always the leanest/hottest of the bunch..
I have ran dual M15 nozzles for 11k miles, and never noticed a difference on the #1 & 2 cyls.
I do think that e85 is a better fix for this though. I'll likely be going to E85 and dropping the meth down to dual M10s.
03-25-2016, 08:12 AM
#56
Burning Brakes
Can someone see it from the manifold pic above?
Well, maybe the previous sentence has too many if's? :-) But anyway, I guess you do not monitor EGT's and also haven't had any knock on front cylinders, which is good of course.
03-25-2016, 11:34 AM
#57
Actually if you want to get academic on me it would abductive reasoning. Really it can be any form of reason depending on how my conclusions were drawn.
Come get your hoopty through tech inspection up here at a real NHRA track and then you can go back to telling Corvette forum how cool you are for racing in the 1/4 mile once every 3 years.
Until then I'll be driving my car...because it actually runs
Come get your hoopty through tech inspection up here at a real NHRA track and then you can go back to telling Corvette forum how cool you are for racing in the 1/4 mile once every 3 years.
Until then I'll be driving my car...because it actually runs
Last edited by Milan; 03-25-2016 at 11:35 AM.
03-25-2016, 02:23 PM
#58
part of it is because the manifold is designed for air flow and methanol or fuel/nitrous have different weights and flow characteristics, mostly because they are "heavier" and so have momentum to them. to be non scientific.
I think doug was loggin over 1/2 mile and standing mile pulls and seeing 300* differences. not sure what you use your car for aj but I'm sure a 1/4 mile would show less of an issue.
Doug has run 8 second cars and has EGT data to back it up so to claim there is no difference with meth on the front two cylinders, you can have your opinion but I'm going with the guy who builds thousands of supercharged vettes and logged results with individual cylinder EGT sensors. I think with logged data across more than just one intake manifold and more than just one setup, it's not really up for debate but you can of course believe what you want.
best i can tell about #7/8 running different is because of the coolant flow. the australian fwd cars or other setups in sand rails, boats, etc where they flip the intake manifold, #7 and #8 still run leaner/hotter so it's not the intake manifold. my #5 doesn't run leaner at least just reading the plugs, it's 7/8 for me but mostly just 7.
one trick I use is to read the plugs and see which cylinders are running hottest/leanest and then just put my highest flowing injectors on those cylinders.
I'd love to run e85 but it's not readily available in my area.
I think doug was loggin over 1/2 mile and standing mile pulls and seeing 300* differences. not sure what you use your car for aj but I'm sure a 1/4 mile would show less of an issue.
Doug has run 8 second cars and has EGT data to back it up so to claim there is no difference with meth on the front two cylinders, you can have your opinion but I'm going with the guy who builds thousands of supercharged vettes and logged results with individual cylinder EGT sensors. I think with logged data across more than just one intake manifold and more than just one setup, it's not really up for debate but you can of course believe what you want.
best i can tell about #7/8 running different is because of the coolant flow. the australian fwd cars or other setups in sand rails, boats, etc where they flip the intake manifold, #7 and #8 still run leaner/hotter so it's not the intake manifold. my #5 doesn't run leaner at least just reading the plugs, it's 7/8 for me but mostly just 7.
one trick I use is to read the plugs and see which cylinders are running hottest/leanest and then just put my highest flowing injectors on those cylinders.
I'd love to run e85 but it's not readily available in my area.
Last edited by neverstop; 03-25-2016 at 02:26 PM.
03-25-2016, 02:35 PM
#59
Le Mans Master
Actually if you want to get academic on me it would abductive reasoning. Really it can be any form of reason depending on how my conclusions were drawn.
Come get your hoopty through tech inspection up here at a real NHRA track and then you can go back to telling Corvette forum how cool you are for racing in the 1/4 mile once every 3 years.
Until then I'll be driving my car...because it actually runs
Come get your hoopty through tech inspection up here at a real NHRA track and then you can go back to telling Corvette forum how cool you are for racing in the 1/4 mile once every 3 years.
Until then I'll be driving my car...because it actually runs
Oh snap....
