New headers/exhaust for the '85/'86 people! Updated with baseline dyno charts.
05-24-2014, 01:04 PM
#16
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Those look very nice.
On the program that some of use for seeing what changes may do what to a certain package, I have found that shorter, larger headers work to increase power up above 4500 while not sacrificing much below that rpm. As in 1-7/8 inch headers, and quite short primaries.
Yes, Long tube headers on a 928, and an E55 (new addition) seem to really add power - especially when there is boost (stock on E55).
With our cars, its almost as important to be able to get that bell housing off as it is to add power!
On the program that some of use for seeing what changes may do what to a certain package, I have found that shorter, larger headers work to increase power up above 4500 while not sacrificing much below that rpm. As in 1-7/8 inch headers, and quite short primaries.
Yes, Long tube headers on a 928, and an E55 (new addition) seem to really add power - especially when there is boost (stock on E55).
With our cars, its almost as important to be able to get that bell housing off as it is to add power!
05-24-2014, 01:07 PM
#17
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05-24-2014, 01:14 PM
#18
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It will be interesting to see if the headers make much of a difference on a S3.
Looks nice, but for all the expense, I don't see it getting much over 320 rwhp dynojet, especially if you revert to 'tuned' stock chips.
The S3 intake/heads/valve size is more of a limiter than the exhaust, AFAIK.
MSDS (or Chinese) headers will probably make similar numbers, with the intake restriction.
Didn't Louie take off a set off of a GT because it made less power than an X-pipe?
Looks nice, but for all the expense, I don't see it getting much over 320 rwhp dynojet, especially if you revert to 'tuned' stock chips.
The S3 intake/heads/valve size is more of a limiter than the exhaust, AFAIK.
MSDS (or Chinese) headers will probably make similar numbers, with the intake restriction.
Didn't Louie take off a set off of a GT because it made less power than an X-pipe?
05-24-2014, 01:16 PM
#19
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Airbox temp is critical to consistent and reliable dyno results with a S3 (with any chip). Try to keep it below 100F for the least amount of ignition retard.
If you do not do so already, I highly recommend a Blue Blower placed over the airbox as shown below, to blow on the air temp sensor and MAF.
You may find the MAF CO needs to be adjusted with the headers. If you are running the headers with S3.S300s chips and find you need more fuel at WOT even after adjusting the MAF CO, plugging the LH brown wire plugs together (never the EZ green wire plugs) will richen it up a bit.
If you do not do so already, I highly recommend a Blue Blower placed over the airbox as shown below, to blow on the air temp sensor and MAF.
You may find the MAF CO needs to be adjusted with the headers. If you are running the headers with S3.S300s chips and find you need more fuel at WOT even after adjusting the MAF CO, plugging the LH brown wire plugs together (never the EZ green wire plugs) will richen it up a bit.
However, I know that you've done a ton of data gathering on these '85/'86 engines in order to develop your chips...so I'd really appreciate you sharing some of that data.
Are 100 degree temperatures at the airflow meter achievable on a vehicle, going down the road, with the hood closed, on an 85 degree day?
05-24-2014, 01:25 PM
#21
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Yes, close to fitting.
I'm going to make pipes and exhaust for the 16 valve vehicles, next.
There's a painful lack of quality pieces that can be used to boost the power output on these engines and there are enough people with really nice cars asking for something to add.
The obvious problem is cost. A stainless set of headers and exhaust isn't cheap...many of these cars are worth less than what it takes to build a stainless system.
I'm going to make pipes and exhaust for the 16 valve vehicles, next.
There's a painful lack of quality pieces that can be used to boost the power output on these engines and there are enough people with really nice cars asking for something to add.
The obvious problem is cost. A stainless set of headers and exhaust isn't cheap...many of these cars are worth less than what it takes to build a stainless system.
05-24-2014, 01:28 PM
#22
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I'm always very reluctant to add anything to a dyno test that can't be added to a road going vehicle....seems like it would interfere with realistic results.
Are 100 degree temperatures at the airflow meter achievable on a vehicle, going down the road, with the hood closed, on an 85 degree day?
Are 100 degree temperatures at the airflow meter achievable on a vehicle, going down the road, with the hood closed, on an 85 degree day?
S3 results can vary up to 20 rwhp unless you can control the air temp. IIRC, full retard on the stock chips is at 125F (variable from 105F-up?).
Airflow temps are near ambient when driving. (FWIW, Porsche DIN standard expects quite cool temps.)
Note 1: the smaller S3 air tubes and upper airbox lid ends will likely be a restriction.
Note 2: I no longer make them, but I have a slightly used WOTpot (from my white car) to finely adjust WOT AFR with the S3.300s chips that I can send the owner. (Probably won't need it though, after adjusting the MAF.)
05-24-2014, 01:30 PM
#23
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Yes, close to fitting.
I'm going to make pipes and exhaust for the 16 valve vehicles, next.
There's a painful lack of quality pieces that can be used to boost the power output on these engines and there are enough people with really nice cars asking for something to add.
The obvious problem is cost. A stainless set of headers and exhaust isn't cheap...many of these cars are worth less than what it takes to build a stainless system.
I'm going to make pipes and exhaust for the 16 valve vehicles, next.
There's a painful lack of quality pieces that can be used to boost the power output on these engines and there are enough people with really nice cars asking for something to add.
The obvious problem is cost. A stainless set of headers and exhaust isn't cheap...many of these cars are worth less than what it takes to build a stainless system.
05-24-2014, 01:35 PM
#24
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You talking about my old very brown 1980 ???
05-24-2014, 04:44 PM
#26
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It will be interesting to see if the headers make much of a difference on a S3.
Looks nice, but for all the expense, I don't see it getting much over 320 rwhp dynojet, especially if you revert to 'tuned' stock chips.
The S3 intake/heads/valve size is more of a limiter than the exhaust, AFAIK.
MSDS (or Chinese) headers will probably make similar numbers, with the intake restriction.
Didn't Louie take off a set off of a GT because it made less power than an X-pipe?
Looks nice, but for all the expense, I don't see it getting much over 320 rwhp dynojet, especially if you revert to 'tuned' stock chips.
The S3 intake/heads/valve size is more of a limiter than the exhaust, AFAIK.
MSDS (or Chinese) headers will probably make similar numbers, with the intake restriction.
Didn't Louie take off a set off of a GT because it made less power than an X-pipe?
There's always the chance something that is made will not work....but there's a lot of engineering in these pipes.
They are about as close to a set of MSDS headers as MSDS are to stock manifolds.
The dynos we use, for testing, are less "optimistic" than other dynos around the country.
Therefore, I sincerely doubt that this car (or if any) S3 car will make 320 rwhp (or even 300rwhp) with any chip change, but we are going to make sure everything is in perfect condition, check all the injection, check for full throttle, and do a base line test.
If you have a method if enriching the mixture of your chips and would like me to use it to work with your chips, I'd be happy to try it.
Otherwise, I'll use Sharktuner to make changes and burn a new set of chips.
05-24-2014, 04:57 PM
#27
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wow
How about an as-is baseline, then stock, then header-tune?
I really appreciate the all-motor mods and final configurations that some folks are able to either 1) do themselves or 2) bankroll.
With the note about actual value of many of the cars themselves vs. the cost of moderate rebuilds and/or headers/stainless systems, I think the best bang for the buck is going to remain nitrous, though I've only read one good enthusiast-build-thread (not Brett, his ambitions were a bit beyond what I'm thinking of..). It ups the risk factor a hair, but in the end even the cars pushing 8lbs have to be very concerned with anything that leads to lean fuel/advanced timing in the same manner.
Look forward to results, price points on these. And hopefully an audio clip/movie of the final product!
I really appreciate the all-motor mods and final configurations that some folks are able to either 1) do themselves or 2) bankroll.
With the note about actual value of many of the cars themselves vs. the cost of moderate rebuilds and/or headers/stainless systems, I think the best bang for the buck is going to remain nitrous, though I've only read one good enthusiast-build-thread (not Brett, his ambitions were a bit beyond what I'm thinking of..). It ups the risk factor a hair, but in the end even the cars pushing 8lbs have to be very concerned with anything that leads to lean fuel/advanced timing in the same manner.
Look forward to results, price points on these. And hopefully an audio clip/movie of the final product!
05-24-2014, 05:23 PM
#28
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I measured air filter temp sensor readings while driving my S2 during development of my 16v performance chips. I found that under normal driving, intake temps are easily held below the point at which the retard is triggered.
However spending quite a short time with the hot engine at idle and car stationary, the intake temp rose very quickly to the retard point.
Further investigation showed that the trigger point was lower than what might have been expected, due to the way the map was structured. We rescaled the map to make it easier to more gradually apply the retard as the temps rose.
However spending quite a short time with the hot engine at idle and car stationary, the intake temp rose very quickly to the retard point.
Further investigation showed that the trigger point was lower than what might have been expected, due to the way the map was structured. We rescaled the map to make it easier to more gradually apply the retard as the temps rose.
Thanks for the feedback on the intake temperatures.
There's always the chance something that is made will not work....but there's a lot of engineering in these pipes.
They are about as close to a set of MSDS headers as MSDS are to stock manifolds.
The dynos we use, for testing, are less "optimistic" than other dynos around the country.
Therefore, I sincerely doubt that this car (or if any) S3 car will make 320 rwhp (or even 300rwhp) with any chip change, but we are going to make sure everything is in perfect condition, check all the injection, check for full throttle, and do a base line test.
If you have a method if enriching the mixture of your chips and would like me to use it to work with your chips, I'd be happy to try it.
Otherwise, I'll use Sharktuner to make changes and burn a new set of chips.
There's always the chance something that is made will not work....but there's a lot of engineering in these pipes.
They are about as close to a set of MSDS headers as MSDS are to stock manifolds.
The dynos we use, for testing, are less "optimistic" than other dynos around the country.
Therefore, I sincerely doubt that this car (or if any) S3 car will make 320 rwhp (or even 300rwhp) with any chip change, but we are going to make sure everything is in perfect condition, check all the injection, check for full throttle, and do a base line test.
If you have a method if enriching the mixture of your chips and would like me to use it to work with your chips, I'd be happy to try it.
Otherwise, I'll use Sharktuner to make changes and burn a new set of chips.
05-25-2014, 06:22 AM
#30
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I checked my notes from the test session I did with my car and also measurements on the bench using the Sharktuner. I found the temp retard comes in earlier than the map might suggest, from 40degC (103degF).
The ambient temp while the car was moving was between 24 and 29degC.
With the car stopped, the time taken for the temp to rise to 53degC which was well into retard was less than a minute. For it to recover to non-retard temps when moving again was about a mile.
When stopped in traffic it went into retard in < 1min
With the car stationary at idle and hood open (like when on a dyno) the temp quickly reached 59degC (140degF). So a fan on the airbox is required.
The ambient temp while the car was moving was between 24 and 29degC.
With the car stopped, the time taken for the temp to rise to 53degC which was well into retard was less than a minute. For it to recover to non-retard temps when moving again was about a mile.
When stopped in traffic it went into retard in < 1min
With the car stationary at idle and hood open (like when on a dyno) the temp quickly reached 59degC (140degF). So a fan on the airbox is required.
