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If you want near positive displacement supercharger spool up, the stock turbo and a turbo back exhaust with tune is the absolute best, but that sacrifices top end. Everything is about compromises.
 

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Without knowing actual turbo specs its a shot in the dark as far as performance goes.
Your example is backwards and i would use 5500rpm as the seperator not 3000rpm (not sure who drives at or below 3000rpm that much)
The larger the turbo the higher the boost threshold so the 1752 is going to have mor "Lag" than the 1446 based turbo simply because it is a larger compressor housing and the larger compressor housing is going to flow more efficiently at higher rpm verses the smaller compressor housing on the 1446.
For low rpm performance (anything below 4000) the stock turbo is going to be the best option but it dies off very quickly after 5000rpm.
the next step would be the EC or NGen 6 fin upgraded 1446 which raises the boost threshold a few hundred rpm from stock but holds boost between 5-6000rpm before tapering off.
The 1752 would be next and the NGen 11 fin GTX style should hold boost to redline with the threshold around 3000+rpm.
It all depends on where you want your power at and that is what makes choosing one of these upgrades so difficult is the lack of information the manufacturers are providing.
Don't forget that there are some people who think the average person is too stupid to read a dyno chart anyway.
 

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If you want near positive displacement supercharger spool up, the stock turbo and a turbo back exhaust with tune is the absolute best, but that sacrifices top end. Everything is about compromises.
True. I'm really happy with the low end but I'm not happy with a 30% drop in power at redline. I'll give up some low end to drop that loss to no more than 10%. Just need to know which solution to pick.
 

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If you want near positive displacement supercharger spool up, the stock turbo and a turbo back exhaust with tune is the absolute best, but that sacrifices top end. Everything is about compromises.
How many vendors sell these turbo back exhausts? Is GWR the only one? Do you mean downpipe?

Would the upgraded manifold paired with the stock turbo be worth it?
 

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Discussion Starter #127
Found the post I was looking for.
Maybe I'll go 1752 with a port polish..
Just gotta wait for the next sale at EC lol
 

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Found the post I was looking for.
Maybe I'll go 1752 with a port polish..
Just gotta wait for the next sale at EC lol
Doesn’t the 1752 have more installation complications than the stuffed 1446?
 

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Found the post I was looking for.
Maybe I'll go 1752 with a port polish..
Just gotta wait for the next sale at EC lol
Seth, I'd love to see you do this. Don't wait! 29 PSI is still a lot of boost. I'm baffled at how we can be talking about running such high boost levels in these cars on 91 octane. Sure, the turbo can push 32 PSI but the tuning window at such boost levels to get the timing set right has to be extremely small. How much heat is in that combustion chamber at those boost levels? The potential for knock is huge. I'm sure @Greg is only talking about those running E85 or water/meth injection. I'd never do it on pump gas. And even on E85 and/or water/meth I might want forged pistons.
 

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Seth, I'd love to see you do this. Don't wait! 29 PSI is still a lot of boost. I'm baffled at how we can be talking about running such high boost levels in these cars on 91 octane. Sure, the turbo can push 32 PSI but the tuning window at such boost levels to get the timing set right has to be extremely small. How much heat is in that combustion chamber at those boost levels? The potential for knock is huge. I'm sure @Greg is only talking about those running E85 or water/meth injection. I'd never do it on pump gas. And even on E85 and/or water/meth I might want forged pistons.
I don't think Phase 3 is intended to run that much boost.
 

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Found the post I was looking for.
Maybe I'll go 1752 with a port polish..
Just gotta wait for the next sale at EC lol
@Seth
I dont remember what the conversation was referencing but this information is skewed.
@Greg may chime in again and give us an update.
Non of these turbos are going to carry 32psi very far into the power band without a sever taper and being out of their efficiency range.
Also power below 3000rpm is where all of the compramises are with a larger turbo including the 1752.
Anyone looking to upgrade their turbo are looking for gains above 5000rpm and steadily carrying boost to redline.
If you are worried about power below 3000rpm an upgraded turbo isnt the way to go.
 

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I don't think Phase 3 is intended to run that much boost.
Correct. I was just referring to Greg's post about boost that high. What are you seeing now? 23-25 range?
 

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  1. @Seth
    I dont remember what the conversation was referencing but this information is skewed.
    @Greg may chime in again and give us an update.
    Non of these turbos are going to carry 32psi very far into the power band without a sever taper and being out of their efficiency range.
    Also power below 3000rpm is where all of the compramises are with a larger turbo including the 1752.
    Anyone looking to upgrade their turbo are looking for gains above 5000rpm and steadily carrying boost to redline.
    If you are worried about power below 3000rpm an upgraded turbo isnt the way to go.
    So with update P3 big turbo is lost at low speeds? It is possible to have some time tracking or dyno curves from those who have P3 big turbo,Honestly, without the data to be processed I cannot evaluate the real benefit of the Big Turbo modification, thanks.
 

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Tork posted this graph recently on Facebook. This is an aftermarket turbo with a Stage 1 tune. Tork hasn't released the specifications of this turbo as it still isn't ready for sale as far as I can tell. But this graph perfectly represents the role tuning has to play when upgrading the turbo. You can see the significant loss of torque and power below 4500 RPMs corresponding with gains in torque and power above 4500 RPMs. Every turbo choice presents a compromise. While I want gains in the high end, I'm not sure I would like the reduction of drivability in the lower RPMs. While down on power early, the curves actually look smoother for the larger turbo. I wonder how much of this Tork can improve with the Stage 2 tune?

74114
 

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Tork posted this graph recently on Facebook. This is an aftermarket turbo with a Stage 1 tune. Tork hasn't released the specifications of this turbo as it still isn't ready for sale as far as I can tell. But this graph perfectly represents the role tuning has to play when upgrading the turbo. You can see the significant loss of torque and power below 4500 RPMs corresponding with gains in torque and power above 4500 RPMs. Every turbo choice presents a compromise. While I want gains in the high end, I'm not sure I would like the reduction of drivability in the lower RPMs. While down on power early, the curves actually look smoother for the larger turbo. I wonder how much of this Tork can improve with the Stage 2 tune?

View attachment 74114
I’m sure the tune will work great once it’s out in 4 and a half years.
 
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