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Turbo lag, is it such a big deal?


JamieP

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For me it's all about matching the parts choice and turbo to your desired power band. Peak BHP is a meaningless figure, it's all about power delivery.

 

Jamie for exmaple drives the car hard and seems to spend most of the time in the top third of the engine rpm and makes full use of the power available. This suits a larger turbo, higher lift cams, lots of fueling, high end ECU, etc to get the most amount of power in that rpm band.

 

My driving style (and that of a few others) is very different. I don't drive the car hard and love having a large amount of low/mid range torque. It's more about having effortless power at lower range. As such the T67dbb setup with stock cams and decent fueling and ECU was perfectly matched to my driving style. I wouldn't want to sacrifice that low end torque for a more powerful high end as 99% of my time behind the wheel would not be spent in that high rpm band.

 

 

I understand fully why some people like Jamie would prefer a larger turbo setup and a more peaky power band, but it's not for everyone.

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For me it's all about matching the parts choice and turbo to your desired power band. Peak BHP is a meaningless figure, it's all about power delivery.

 

Jamie for exmaple drives the car hard and seems to spend most of the time in the top third of the engine rpm and makes full use of the power available. This suits a larger turbo, higher lift cams, lots of fueling, high end ECU, etc to get the most amount of power in that rpm band.

 

My driving style (and that of a few others) is very different. I don't drive the car hard and love having a large amount of low/mid range torque. It's more about having effortless power at lower range. As such the T67dbb setup with stock cams and decent fueling and ECU was perfectly matched to my driving style. I wouldn't want to sacrifice that low end torque for a a more powerful high end as 99% of my time behind the wheel would not be spent in that high rpm band.

 

 

I understand fully why some people like Jamie would prefer a larger turbo setup and a more peaky power band, but it's not for everyone.

 

I'd empathise with that. I am soo not enjoying the drive of my T67 in comparison to my old supra with BPU as far as it could go. With mine being an auto and now back on a stock ecu not even gear selectable any more keeping the car on the power is very difficult without thrashing the living hell out of it. The gear ranges are way too long to stay in the power band especially at road legal speeds. When you belt off the line and keep your foot down the power is awesome and relentless and just keeps coming. The moment you come off the pedal its gone and there is that annoying up change into an innapropriatte gear with revs drop off and a woefully slow resumption of power. Its infuriating when you accelerate to overtake a car, the power comes in and you start to catch the car in front ready to pull out when the oncoming vehicle has passed only for the oncoming car to have slowed or miss-judged timing and you have to lift off the gas even momentarily. You come out into the overtake maneuovre with no bloody boost and the wrong frickin gear until it kicks down and the boost builds back up again. I've had it a couple of times where it didn't bother kicking down and that was awful.

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I'd empathise with that. I am soo not enjoying the drive of my T67 in comparison to my old supra with BPU as far as it could go. With mine being an auto and now back on a stock ecu not even gear selectable any more keeping the car on the power is very difficult without thrashing the living hell out of it. The gear ranges are way too long to stay in the power band especially at road legal speeds. When you belt off the line and keep your foot down the power is awesome and relentless and just keeps coming. The moment you come off the pedal its gone and there is that annoying up change into an innapropriatte gear with revs drop off and a woefully slow resumption of power. Its infuriating when you accelerate to overtake a car, the power comes in and you start to catch the car in front ready to pull out when the oncoming vehicle has passed only for the oncoming car to have slowed or miss-judged timing and you have to lift off the gas even momentarily. You come out into the overtake maneuovre with no bloody boost and the wrong frickin gear until it kicks down and the boost builds back up again. I've had it a couple of times where it didn't bother kicking down and that was awful.

 

Thats just a bad setup, Gamers orange beast was a awesome car on the auto box and that was with a 71mm turbo, was nothing like what you are saying.

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For me it's all about matching the parts choice and turbo to your desired power band. Peak BHP is a meaningless figure, it's all about power delivery.

 

Jamie for exmaple drives the car hard and seems to spend most of the time in the top third of the engine rpm and makes full use of the power available. This suits a larger turbo, higher lift cams, lots of fueling, high end ECU, etc to get the most amount of power in that rpm band.

 

My driving style (and that of a few others) is very different. I don't drive the car hard and love having a large amount of low/mid range torque. It's more about having effortless power at lower range. As such the T67dbb setup with stock cams and decent fueling and ECU was perfectly matched to my driving style. I wouldn't want to sacrifice that low end torque for a a more powerful high end as 99% of my time behind the wheel would not be spent in that high rpm band.

 

 

I understand fully why some people like Jamie would prefer a larger turbo setup and a more peaky power band, but it's not for everyone.

 

 

Could be one of the best posts I have read and should be read by anyone wanting to chase the BHP monster and looking to spend the tens of thousands a good single car can cost :)

 

I have chased big BHP, seen stupid road power well over 700BHP BUT I have to say I drive like miss daisy most of the time and only wanted the cudos of a big UK BHP car, the power once I started getting to 500+ used to scare me half the time,my driving skill was just not really up to it if I am honest, I think this is a factor when you are looking for a quick car, I found that the BPU Supra is the perfect compromise, quick, fast spool, reliable and easy to live with

 

I love big BHP power cars but I dont see me really doing it again (have owned several single turbo cars),I fancy low end torque from a V8

 

Still very interested in the quest for power and what a 3 litre engine can deliver, I have to say I am also a little sad not to be involved but that is soon forgotten with the thought of the expense in the past :)

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Could be one of the best posts I have read and should be read by anyone wanting to chase the BHP monster and looking to spend the tens of thousands a good single car can cost :)

 

Thanks mate, with this thread I was getting worried that the single turbo FAQ I'm working on would be a waste of time. It's 6 pages so far am only scratching the surface of the considerations. I'll certainly take into account a few of the comments made here though, there are some very valid ones.

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For me it's all about matching the parts choice and turbo to your desired power band. Peak BHP is a meaningless figure, it's all about power delivery.

 

Jamie for exmaple drives the car hard and seems to spend most of the time in the top third of the engine rpm and makes full use of the power available. This suits a larger turbo, higher lift cams, lots of fueling, high end ECU, etc to get the most amount of power in that rpm band.

 

My driving style (and that of a few others) is very different. I don't drive the car hard and love having a large amount of low/mid range torque. It's more about having effortless power at lower range. As such the T67dbb setup with stock cams and decent fueling and ECU was perfectly matched to my driving style. I wouldn't want to sacrifice that low end torque for a a more powerful high end as 99% of my time behind the wheel would not be spent in that high rpm band.

 

 

I understand fully why some people like Jamie would prefer a larger turbo setup and a more peaky power band, but it's not for everyone.

 

Top post mate :thumbs:

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My driving style (and that of a few others) is very different. I don't drive the car hard and love having a large amount of low/mid range torque. It's more about having effortless power at lower range. As such the T67dbb setup with stock cams and decent fueling and ECU was perfectly matched to my driving style. I wouldn't want to sacrifice that low end torque for a a more powerful high end as 99% of my time behind the wheel would not be spent in that high rpm band.

 

 

I understand fully why some people like Jamie would prefer a larger turbo setup and a more peaky power band, but it's not for everyone.

 

Good post, as you say everyone wants something different from there car.

 

As you know my car has plenty of low/mid range torque, thing is i dont really use it, i either drive slowly, and im nowhere near using the midrange, or i want to go for it and im way past the midrange.

 

Im not saying i want a laggy car, but to lose a little spool for a lot more top end sounds good to me.

 

Saying all that though, with a little more revs i may max out pump fuel and the turbo and have my perfect setup already.:search:

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For me this was the perfect street setup as it didn't matter what gear I was in I would always get instant response when I put my foot down. Basically the only time I experienced turbo lag was when pulling away from a stand still.

 

For me too......plenty of torque and not that noticeable lag at all.

 

Revving the crap out of the car in every gear is not something that I do on busy public roads. for a street setup, reducing lag is extremely important - IMO.

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Completely agree with Homer there. When I was choosing the turbo for my MR2 V6 project, that was totally the rational behind it. I sampled a few turbos, namely Jay's 4088r on the 3l. I had 400c more to play with and went one size bigger. I wanted the low end torque and driveability, instant power, effortless overtake the lot.

 

Horses for courses!

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Whats the point though? i very much doubt pump fuel will get anywhere near 2.5bar without a very drastic reduce in timing, i doubt power would go up.:)

 

What if you drop the CR down to something around 8:1? You'll lose off boost, but you'll get more top end boost, which is what you're after?

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