Engine dyno testing with temperatures
Thread Starter
Joined: Mar 2005
Posts: 666
Likes: 2
From: Holland
Engine dyno testing with temperatures
Hi guys,
last year I bought the IP intake and finally we're tuning the engine.
We installed egt sensors on all 4 exhaust outputs and running the car at 2500
rpm. What we see is a 10% difference in temperature betweem number1/2 and 3/4.
So for instance 1 and 2 are 500 degrees C and 3 and 4 are 550.
Does anyone know what the flow characteristics are of the IP intake? Is this
normal? We're a bit conserned. Will it level out at higher rpm and boost?
Pfab twin scroll manifold
Bosch 2000cc injectors (replaced the 1600 since engine damage from them in february)
AEM EMS Series 2
InlinePro intake manifold
Setup
@1500 rpm
@2500 rpm
last year I bought the IP intake and finally we're tuning the engine.
We installed egt sensors on all 4 exhaust outputs and running the car at 2500
rpm. What we see is a 10% difference in temperature betweem number1/2 and 3/4.
So for instance 1 and 2 are 500 degrees C and 3 and 4 are 550.
Does anyone know what the flow characteristics are of the IP intake? Is this
normal? We're a bit conserned. Will it level out at higher rpm and boost?
Pfab twin scroll manifold
Bosch 2000cc injectors (replaced the 1600 since engine damage from them in february)
AEM EMS Series 2
InlinePro intake manifold
Setup
@1500 rpm
@2500 rpm
Registered User
Joined: May 2008
Posts: 3,791
Likes: 1
From: Around
3 and 4 are known to be the hot cylinders. We have had quite a few discussions on this over the years, and even one of the past 2 weeks.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
Registered User
Joined: Jul 2009
Posts: 331
Likes: 1
From: Northampton/Leeds
I use FlashPro so I am not familiar with AEM EMS, can't you adjust individual cylinder fueling trims? If so take fuel away from the cylinders that are running cooler and add fuel to the cylinders that are running hotter untill all cylinders are roughly at the average of the current temperature spread..that way your overall AFR will remain as it is at present.
(obviously if you can't do this with EMS ignore what I said.)
Dan
(obviously if you can't do this with EMS ignore what I said.)
Dan
Thread Starter
Joined: Mar 2005
Posts: 666
Likes: 2
From: Holland
3 and 4 are known to be the hot cylinders. We have had quite a few discussions on this over the years, and even one of the past 2 weeks.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
If the injectors are equal and the intake isn't any worse than stock it will be fine. It's normal to have a bit of a spread until it's loaded up. If you poke around on the web enough you will find some good reading on tuning individual cylinders. Just keep in mind EGT's get cooler with timing and you can burn one up riding the curve down.
Thanks
Jay Meagher
Thanks
Jay Meagher
I use FlashPro so I am not familiar with AEM EMS, can't you adjust individual cylinder fueling trims? If so take fuel away from the cylinders that are running cooler and add fuel to the cylinders that are running hotter untill all cylinders are roughly at the average of the current temperature spread..that way your overall AFR will remain as it is at present.
(obviously if you can't do this with EMS ignore what I said.)
Dan
(obviously if you can't do this with EMS ignore what I said.)
Dan
Obviously it's also alot of work.
How do others do this, almost nobody installs 4 egt sensors so most tuners are working with 1 temperature?
Registered User
Joined: Aug 2009
Posts: 876
Likes: 0
From: Richmond, VA
Originally Posted by siadam' timestamp='1313615910' post='20888023
3 and 4 are known to be the hot cylinders. We have had quite a few discussions on this over the years, and even one of the past 2 weeks.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
Simply by design, 4 is going to get the least amount of air, and will tend to run leaner, while cylinder 3 is sandwiched between 2 and 4 and runs hot.
If the injectors are equal and the intake isn't any worse than stock it will be fine. It's normal to have a bit of a spread until it's loaded up. If you poke around on the web enough you will find some good reading on tuning individual cylinders. Just keep in mind EGT's get cooler with timing and you can burn one up riding the curve down.
Thanks
Jay Meagher
Thanks
Jay Meagher
I use FlashPro so I am not familiar with AEM EMS, can't you adjust individual cylinder fueling trims? If so take fuel away from the cylinders that are running cooler and add fuel to the cylinders that are running hotter untill all cylinders are roughly at the average of the current temperature spread..that way your overall AFR will remain as it is at present.
(obviously if you can't do this with EMS ignore what I said.)
Dan
(obviously if you can't do this with EMS ignore what I said.)
Dan
Obviously it's also alot of work.
How do others do this, almost nobody installs 4 egt sensors so most tuners are working with 1 temperature?
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Registered User
Joined: May 2008
Posts: 3,791
Likes: 1
From: Around
Ring seal, intake/exhaust manifold design, head design, differences in injectors, no matter how small all play a role in the outcome in each cylinder, especially when you compare 4/6/8/+ cylinder motors.
Banned
Joined: May 2002
Posts: 3,624
Likes: 11
From: Raleigh, NC
Originally Posted by wadzii' timestamp='1313671552' post='20889751
get it loaded up and do a few lower boost pulls and see what you see.
from what i have seen, they do run differently, but not enough to do the work to "fix"
from what i have seen, they do run differently, but not enough to do the work to "fix"
Ring seal, intake/exhaust manifold design, head design, differences in injectors, no matter how small all play a role in the outcome in each cylinder, especially when you compare 4/6/8/+ cylinder motors.