Differences in S3 and S4 engines
#16
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Wow, thank you all for this great info. I have learned more new info about my car, I thought it was 288 HP like Wikipedia says, but as I can see that was wrong. I guess I have a few options if I want more HP, get a GTS...lol I wish, install Pken S300 chip ( I don;t think I will since I want to keep the car original as much, install high flow cats, I might do this in combination with the X-Pipe, which should provide me around 27 to 29 HP extra which should bring me in the range of the S4. Again thank you all, this forum is such a great resource to have, real experts. ![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
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Just saying that you will probably get more bang for your time/dollar with the chips.
#17
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Definitely consider the S300 chips as it will be much easier to install the old ones back (to keep it original) as well as the spark plugs and FPR than the exhaust. But if you want full "bolt-on" fun that can be changed back do both ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
Just saying that you will probably get more bang for your time/dollar with the chips.
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Just saying that you will probably get more bang for your time/dollar with the chips.
Is it Fuel Pressure Rail ?
I have just purchased my baby in 2013 and 2014 was my first year of enjoyment. I have a long way to go to understand the mechanics of this car, since I am not mechanically inclined by default, I'm a computer guy.
#18
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I did a quick Google search and found it to be Fuel Pressure Regulator, sorry.
I gather if I do decide to add the S300 chip, I will need to get the car tuned with a shark tuner and all ?
I have none of those tools, so I would need to get it done by someone here in Canada, if any.
IIRC, I thought I heard that your top end has to be in the best of shape before using a S300 chip otherwise I am asking for trouble. Currently the car is running great, but one thing I would like to to in the next two years is a top end refresh, intake, plugs, wires and other related duties WYIT !
I gather if I do decide to add the S300 chip, I will need to get the car tuned with a shark tuner and all ?
I have none of those tools, so I would need to get it done by someone here in Canada, if any.
IIRC, I thought I heard that your top end has to be in the best of shape before using a S300 chip otherwise I am asking for trouble. Currently the car is running great, but one thing I would like to to in the next two years is a top end refresh, intake, plugs, wires and other related duties WYIT !
#19
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if you do Porken's chips there's a process to adjust the mixture....assuming you have a good MAF.
I went back to stock plugs in my Porkenized S3 and started enriching the mixture....was able to get more power by going into the "rich" area per the Ken method....not sure why...and yes...mileage is in the toilet
I went back to stock plugs in my Porkenized S3 and started enriching the mixture....was able to get more power by going into the "rich" area per the Ken method....not sure why...and yes...mileage is in the toilet
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#20
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The '85-'86 lacks knock sensors which requires a more conservative timing curve = less power. You can get really close to the S4 engine power with tuning and adding knock sensors. My '86.5 went from 240-ish RWHP to 275 RWHP with aftermarket ECU, knock sensors added and re-tuning. Can probably get close by adding some Porken chips and shark tuning the stock ECU.
Of course the intake is different, cams are more aggressive (similar to GT cams), computers are different.
Cheers!
Carl
Of course the intake is different, cams are more aggressive (similar to GT cams), computers are different.
Cheers!
Carl
85 flatter pistons, greater combustion chamber size
S4 dished pistons and smaller combustion size
net compression is higher on the S4 (9.3:1 vs 10:1)
the 85 uses the 2 disc clutch (25lbs less) too.
net net, the S4 is the better motor, but there is rumor , all things being equal, that 85 intake might make more power. but we have never seen it done!
i got 290 bone stock with no cats
335rwhp with headers and air box venting and a RRFR set at 12.6:1
I think if you have an 85, you put on S4 heads, which will get that compression to near 11.5, use the RRFR. (rising rate fuel reg ) and you will have a safe screamer.
i run the stroker with stock S4 heads and near flat pistons as well... compression is near 11.2:1 and i still use pump gas with no issues
Mk
#21
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Thanks Tim, I will keep that in mind. What does FPR stand for again, working for the government my mind is so full of acronyms that I loose track. LOL Is it Fuel Pressure Rail ? I have just purchased my baby in 2013 and 2014 was my first year of enjoyment. I have a long way to go to understand the mechanics of this car, since I am not mechanically inclined by default, I'm a computer guy.
Back to the chips, essentially this is something you can do yourself and is a great opportunity to learn more about your car (especially the prework). What you will be looking at is doing a basic tune-up and replacing the spark plugs with "cooler" ones. You swap your FPR from an S4 one (buy a new one off amazon ideally) and make sure all your intake pieces are working fine. Check out Ken's website or give Roger a call. It may sound intimidating but short of changing your oil, this will be one of the easier things to do on your car and with me at least, I felt just tinkering around made a real connection with the car. Also you would have to really mess something up to do serious damage with something like this, so small amounts of trial and error are ok.
Good luck and welcome to the club, hopefully working on your baby becomes more therapeutic. Then the maintenance bills don't look like mortgage payments anymore!
#22
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cams are more aggressive on the 85 vs the S4, ironically enough. (more lift) BUT, the heads have smaller valves... thats the trade off.
85 flatter pistons, greater combustion chamber size
S4 dished pistons and smaller combustion size
net compression is higher on the S4 (9.3:1 vs 10:1)
the 85 uses the 2 disc clutch (25lbs less) too.
net net, the S4 is the better motor, but there is rumor , all things being equal, that 85 intake might make more power. but we have never seen it done!
i got 290 bone stock with no cats
335rwhp with headers and air box venting and a RRFR set at 12.6:1
I think if you have an 85, you put on S4 heads, which will get that compression to near 11.5, use the RRFR. (rising rate fuel reg ) and you will have a safe screamer.
i run the stroker with stock S4 heads and near flat pistons as well... compression is near 11.2:1 and i still use pump gas with no issues
Mk
85 flatter pistons, greater combustion chamber size
S4 dished pistons and smaller combustion size
net compression is higher on the S4 (9.3:1 vs 10:1)
the 85 uses the 2 disc clutch (25lbs less) too.
net net, the S4 is the better motor, but there is rumor , all things being equal, that 85 intake might make more power. but we have never seen it done!
i got 290 bone stock with no cats
335rwhp with headers and air box venting and a RRFR set at 12.6:1
I think if you have an 85, you put on S4 heads, which will get that compression to near 11.5, use the RRFR. (rising rate fuel reg ) and you will have a safe screamer.
i run the stroker with stock S4 heads and near flat pistons as well... compression is near 11.2:1 and i still use pump gas with no issues
Mk
I don't think I will be going that far as changing the heads to an S4, unless I have major problems with my original heads.
#23
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Yep you got it right on Fuel Pressure Regulator! And congrats for starting to enjoy her, that is what I love about mine, it is my only car so I need to be able to enjoy it most of the time. I too am in the computer industry but cars will always have a special place in my heart, there is just something about the mechanics that is so interesting considering it is not all circuits and software.
Back to the chips, essentially this is something you can do yourself and is a great opportunity to learn more about your car (especially the prework). What you will be looking at is doing a basic tune-up and replacing the spark plugs with "cooler" ones. You swap your FPR from an S4 one (buy a new one off amazon ideally) and make sure all your intake pieces are working fine. Check out Ken's website or give Roger a call. It may sound intimidating but short of changing your oil, this will be one of the easier things to do on your car and with me at least, I felt just tinkering around made a real connection with the car. Also you would have to really mess something up to do serious damage with something like this, so small amounts of trial and error are ok.
Good luck and welcome to the club, hopefully working on your baby becomes more therapeutic. Then the maintenance bills don't look like mortgage payments anymore!
Back to the chips, essentially this is something you can do yourself and is a great opportunity to learn more about your car (especially the prework). What you will be looking at is doing a basic tune-up and replacing the spark plugs with "cooler" ones. You swap your FPR from an S4 one (buy a new one off amazon ideally) and make sure all your intake pieces are working fine. Check out Ken's website or give Roger a call. It may sound intimidating but short of changing your oil, this will be one of the easier things to do on your car and with me at least, I felt just tinkering around made a real connection with the car. Also you would have to really mess something up to do serious damage with something like this, so small amounts of trial and error are ok.
Good luck and welcome to the club, hopefully working on your baby becomes more therapeutic. Then the maintenance bills don't look like mortgage payments anymore!
SO I gather if I do the S300 upgrade and the X-Pipe with high flow cats, I can raise my extra HP another ~47 HP ?
I will read up on Ken's site once I find it to see what I need to do to get that extra HP with the S300 chips.
Doing my research prior is a good thing !
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#24
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#25
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Now to do some research on how to test the MAF to match these:
Recomendations:
- Rebuilt MAF (CO 382 ohms)