[Choda]

1:58 Lol

https://youtu.be/ELzLcuSn23o

[parish8]

Originally Posted by Choda

1:58 Lol

https://youtu.be/ELzLcuSn23o

Call me nuts.

To be fair I wouldn’t have considered it if I hadn’t broke my 6.2. I will be funny if it is one of the quicker cars with a budget build 5.3.

[cmitchell17]

Originally Posted by parish8

Call me nuts.

To be fair I wouldn’t have considered it if I hadn’t broke my 6.2. I will be funny if it is one of the quicker cars with a budget build 5.3.

Do you have the intake port cross sectional areas, exhaust port cross sectional areas, runner and collector lengths? I can run a simulation of what you have and come up with cylinder pressure numbers, temps, and some other info in DynoSim.

I am also working on a simulink engine model to back up the DynoSim numbers, but simulink/matlab is dedicated to engineers and scientists, so there is zero user friendliness and you can drive yourself insane trying to stablize models and debug things.

Also i'll need your compressor maps and stuff too.

I would love to have a in cylinder transducer as well, I remember 10 years ago how people were starting to do things themselves like that back then and how they promised in 10 years we will have it made with cheap sensors and all this. It seems like things have gone nowhere, its insane how all the parts still cost just as much as they did back then.

[parish8]

I don’t know any of that.

[cmitchell17]

Originally Posted by parish8

I don’t know any of that.

It's not really that crucial, I can estimate it from the LT1 head I tried to measure. Do you have a compressor map though?

[gtfoxy]

Originally Posted by cmitchell17

It's not really that crucial, I can estimate it from the LT1 head I tried to measure. Do you have a compressor map though?

He posted this a while back in this thread.

https://www.borgwarner.com/matchbot/...6_wrsin=92044&

Maybe it has changed though.

[parish8]

Originally Posted by gtfoxy

He posted this a while back in this thread.

https://www.borgwarner.com/matchbot/...6_wrsin=92044&

Maybe it has changed though.

Precision doesn’t show their maps. That turbo in matchbot is my best guess for the right map.

[cmitchell17]

Here is my first go at it. For some reason it isn't making boost until 6000 rpms and only hits 7psi at 7000 rpms, I'm not sure how much more you'll be spinning it. I've never really messed with turbos or supercharges too much but I'm using the built in map for a BW 8374. This is also with the optimally calculated MBT timing which is realistic, I turned it down to 18 degrees like you mentioned, but it didn't make any torque, I need to figure out what is causing it to limit boost.

Anyway, at 7000 rpms it hits 7.5 psi and peak cylinder pressures of a little under 2000 psi, seems kind of low?

[parish8]

After I cam it I am thinking 7500ish rpm but really don’t know. I am able to build 20psi+ at 4000rpm now, boost building is not an issue. Not really sure what all is going on with your software, looks interesting.

[cmitchell17]

Originally Posted by parish8

After I cam it I am thinking 7500ish rpm but really don’t know. I am able to build 20psi+ at 4000rpm now, boost building is not an issue. Not really sure what all is going on with your software, looks interesting.

I have something wrong in the A/R ratio or the turbine diameter, I am using a generic BW compressor map (they don't have Precision built in):


I'm using a 76mm turbine (2.992in) and a .91 A/R, since its looks like thats the closest the BW software solved for (but apparently it didn't solve to the correct solution since it says that all the dots have to converge to one A/R/diameter line:

[gtfoxy]

Originally Posted by cmitchell17

I have something wrong in the A/R ratio or the turbine diameter, I am using a generic BW compressor map (they don't have Precision built in):
Attachment 1052733

I'm using a 76mm turbine (2.992in) and a .91 A/R, since its looks like thats the closest the BW software solved for (but apparently it didn't solve to the correct solution since it says that all the dots have to converge to one A/R/diameter line:
Attachment 1052732

Doesn’t your turbine side say 1.05?

Also try cranking the timing & leaning it out below 4K rpm.

[cmitchell17]

Originally Posted by gtfoxy

Your turbine side says 1.05.

Also try cranking the timing & leaning it out below 4K rpm.

Yeah you're right, either way I guess its either any one of these 3:



I can make it build boost if I put in a smaller turbine size, here is a 1.850in (46mm):



This program isn't really open source, so I have no way of knowing exactly what its doing, I believe it uses a good bit of empirical data (I believe this makes it more accurate and definitely more user friendly and geared towards non-engineer/non-scientific people. I believe it simulates like an actual dyno operator would run a engine dyno, where its loaded down and allowed to step up through the rpm range and dwell a little at each step to reach steady state, so that's why you see the boost curve has to be built up since I think the initial conditions it starts with is the turbine/compressor is at zero rpms.

Here is the timing it uses (when its set to calculate optimal timing):

Obviously this probably isn't realistic timing, even with E85, so here it is with the 18 degrees I think you mentioned earlier in the thread:

You can see torque and peak cylinder pressure have dropped significantly. The "optimal" "MBT" timing this calculates is not going to be accurate, it requires 3D CFD analysis to come up with that and is impossible to get accurate in 1 dimensional analysis.

[gtfoxy]

Originally Posted by cmitchell17

Yeah you're right, either way I guess its either any one of these 3:
Attachment 1052734


I can make it build boost if I put in a smaller turbine size, here is a 1.850in (46mm):
Attachment 1052735

See my edit & try it again.

Also, his dots are close to the 74mm/.92AR. Turbine maybe try that as well.

[cmitchell17]

Originally Posted by gtfoxy

See my edit & try it again.

Also, his dots are close to the 74mm/.92AR. Turbine

Here is a 74mm/.92 A/R:


I can control AFR to whatever I want, unfortunately I can only ramp in a timing advance and then set it to a constant at a certain RPM, not sure why they don't offer that functionality, but I guess its the old school way of controlling timing just by a ramp and a peak like a distributor setup. You can still have it set to calculate with "optimal" but then again it might not be realistic ie.(30+ degrees).