So making this thread because I want to put down my ideas and share them.
I've been sitting on the wall seeing what is being done to the car engine wise. My goals are:
- keeping the car as stock as possible, I want to keep the car potentially rest of my life and value ease of ownership and long term reliability
- focus on subjective fun in driving - response and enjoyment through the revrange. Don't care about numbers, in fact if it were slower and more fun, that would even be better... Also want the car to feel consistent
- on the above, "it's the new Integrale", but really, even stock it's a missile compared to them all:
(e.g. >5s faster to 100mph)
- "fun for others": keep bystanders happy and so preserving driving freedoms, so no loud antics (but that is easily changed with a cat-back in case that makes you deeply happy). But more importantly, keeping emission compliance, for others but also my own sake, I've exposed myself enough already through the years and noticed my lungs weren't always happy... Also no hassle later on, swapping exhaust for MOT is for youngsters...
- budget: having spent way too much on mods in the past for sometimes very marginal gains in actual driver enjoyment, I'm trying to keep mod count down...
Having owned and properly driven the car, here are my conclusions so far:
A) Off boost response is great
B) Response suffers from heat soak and hot temps (just as any other turbo), affecting response as the turbo must boost more for the same performance, also affecting NA response air temp into the engine are high. Logging shows a single 3rd gear pul around zero degr C results in a IAT rise of, at times, 20 degrees C. Still need to log how IC works in hotter weather.
C) Great torque on boost, 3k to 5k pulls are great fun, in cold weather works well together with initial strong NA reponse
D) Not so much fun to rev out, it is fast but doesn't feel it and feels 'flat'. Basically it doesn't deliver on the power rise earlier on, one wants a crescendo of sorts... Actual power goes down... Or with normal tuning boxes, stays 'level' (see yellow line in below graph)
E) Logging shows engine runs 'lean' AFR's up to 3900rpm WOT.
F) boost but also AFR drop above 4k-ish. Fuel trim drops just before redline, meaning there is extra fuel headroom in the top end...
What I'm planning:
1) E30 fuel (implemented), see https://www.gr-zoo.com/threads/ethanol-blends-e85.629/
Helps prevents timing pull when hotter, lower EGT on boost and helps IAT recovery off boost when port injection is active. Reduces LSPI.
2) For A) B), aftermarket IC but using stock boost pipes. Really any would do, my sights are on Pumaspeeds (edit: Wagner would have been better as it has a proper kit for stock pipes). Keeping IATs low means the ECU will not crank up boost to keep power, meaning better/consistant response. Also NA response remains good. Also look for measures to getting more cold air in the intake when the flap opens.
3) For D), but also helps response in B): HJS EU6d-temp ECE metal cat downpipe
4) For D) E) F): programmable box so I can finetune the power curve to keep increasing power to redline (purple line below) past 4k where AFR's are safe. Not the most area under the curve so not fastest, but also lower load and heat, helping reliability. Basically taking back the hardware gains in reliability margins from 1) 2) and 3) back to stock-ish levels of heat. Logging required for finetuning, probably add very little boost sub 4k just to take home possible response gains from the hardware.
JB4 or upcoming HKS are the candidates right now.
Graph from Diyman dyno graph, hardware with and without (dtuk) box. Yellow line and purple line added.
All this should result in an even more very enjoyable drive, with amazing response also when weather gets hotter and great fun to use the whole revrange. With practically no downside on reliability, longevity and other stuff that are longer term considerations. Strictly speaking warranty is out the window but an understanding technician should at least let you keep unrelated engine warranty.
Above my current ideas. Actual implementation is allowed to take its time.
Feel free to discuss...
I've been sitting on the wall seeing what is being done to the car engine wise. My goals are:
- keeping the car as stock as possible, I want to keep the car potentially rest of my life and value ease of ownership and long term reliability
- focus on subjective fun in driving - response and enjoyment through the revrange. Don't care about numbers, in fact if it were slower and more fun, that would even be better... Also want the car to feel consistent
- on the above, "it's the new Integrale", but really, even stock it's a missile compared to them all:
(e.g. >5s faster to 100mph)
- "fun for others": keep bystanders happy and so preserving driving freedoms, so no loud antics (but that is easily changed with a cat-back in case that makes you deeply happy). But more importantly, keeping emission compliance, for others but also my own sake, I've exposed myself enough already through the years and noticed my lungs weren't always happy... Also no hassle later on, swapping exhaust for MOT is for youngsters...
- budget: having spent way too much on mods in the past for sometimes very marginal gains in actual driver enjoyment, I'm trying to keep mod count down...
Having owned and properly driven the car, here are my conclusions so far:
A) Off boost response is great
B) Response suffers from heat soak and hot temps (just as any other turbo), affecting response as the turbo must boost more for the same performance, also affecting NA response air temp into the engine are high. Logging shows a single 3rd gear pul around zero degr C results in a IAT rise of, at times, 20 degrees C. Still need to log how IC works in hotter weather.
C) Great torque on boost, 3k to 5k pulls are great fun, in cold weather works well together with initial strong NA reponse
D) Not so much fun to rev out, it is fast but doesn't feel it and feels 'flat'. Basically it doesn't deliver on the power rise earlier on, one wants a crescendo of sorts... Actual power goes down... Or with normal tuning boxes, stays 'level' (see yellow line in below graph)
E) Logging shows engine runs 'lean' AFR's up to 3900rpm WOT.
F) boost but also AFR drop above 4k-ish. Fuel trim drops just before redline, meaning there is extra fuel headroom in the top end...
What I'm planning:
1) E30 fuel (implemented), see https://www.gr-zoo.com/threads/ethanol-blends-e85.629/
Helps prevents timing pull when hotter, lower EGT on boost and helps IAT recovery off boost when port injection is active. Reduces LSPI.
2) For A) B), aftermarket IC but using stock boost pipes. Really any would do, my sights are on Pumaspeeds (edit: Wagner would have been better as it has a proper kit for stock pipes). Keeping IATs low means the ECU will not crank up boost to keep power, meaning better/consistant response. Also NA response remains good. Also look for measures to getting more cold air in the intake when the flap opens.
3) For D), but also helps response in B): HJS EU6d-temp ECE metal cat downpipe
4) For D) E) F): programmable box so I can finetune the power curve to keep increasing power to redline (purple line below) past 4k where AFR's are safe. Not the most area under the curve so not fastest, but also lower load and heat, helping reliability. Basically taking back the hardware gains in reliability margins from 1) 2) and 3) back to stock-ish levels of heat. Logging required for finetuning, probably add very little boost sub 4k just to take home possible response gains from the hardware.
JB4 or upcoming HKS are the candidates right now.
Graph from Diyman dyno graph, hardware with and without (dtuk) box. Yellow line and purple line added.
All this should result in an even more very enjoyable drive, with amazing response also when weather gets hotter and great fun to use the whole revrange. With practically no downside on reliability, longevity and other stuff that are longer term considerations. Strictly speaking warranty is out the window but an understanding technician should at least let you keep unrelated engine warranty.
Above my current ideas. Actual implementation is allowed to take its time.
Feel free to discuss...
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