I KNOW what it takes to make EFI system to match the carbs, I just did not want to make this post longer than it is. I have installed and tuned ~50-60 different cars (around 20 Porsches amongst them) with standalones and these include turbocharged, supercharged, NA, ITB etc engines, starting from H-4 to V12 BMW twin turbo and 800 hp/1200 Nm Mercedes AMG 5.5liter twin-plug 3valve supercharged engine (basically the same as SLR McLaren).
Here it is on an engine dyno:
And here's a video:
http://www.otter-ag.ee/files/AMG2.MOV
The SuperFlow AutoDyn dyno we measured the 911 is conservative on the numbers but if you are even remotely familiar with dynos, what matters is before and after numbers.
You are arguing that it is not cheap to put motorcycle ITB's together and find them, yet I have done this numberous times and ebay is full of suitable ITB's. If you don't feel comfortable and other do and make it work, then perhaps the problem is not the others, isn't it?
I remember someone said once that ITB's and turbos don't work well also, you can't possibly take a person serious after such statement. I fabiracted ITB turbo manifold for my 931 race-car, you can see photos in my garage section here in Pelican.
I won't even go with NASCAR carb vs efi, because how can you expect them to get the same or better results with completely new to them solution and not too much of experience? They had like 50years to hone things with carbs but only one year with efi so keeping this in mind I think it is in fact better.
There is no point in taking this further, if one wants to believe something and doesn't want to actullay do something other than saying it's not possible/right/good, then fine. It's your car, not mine, right
Quote:
Originally Posted by lindy 911
Peak HP with EFI is not going to be any different than peak HP with carbs keeping the induction flow the same. Getting from idle to WOT is where EFI has an advantage if there is one.
To build and EFI system that matches the performance of Webers is more than what you describe. Common plenum systems won't get there with regard to throttle response. Individual throttle bodies are not cheap to buy or to build from motorcycle parts. Although these parts can be made to work, not many motorcycles came with 46mm TBs. The Triumph parts in Al's build are 38mm, not near big enough for a hot 3.0.
Your friends 3.6 made 172 rwkw which converts to roughly 230 rwhp if my math is correct. My 3.0 makes close to 240 at 6,800 with Webers and pump gas.
I know an EFI system can be put together with various parts and pieces but it's not what i would call plug and play. I've had a tool box since I was 12 and would not feel comfortable trying this on my own.
As a side note; The NASCAR boys went to EFI this year on top of a manifold. The results? Down about 50 hp across the board compared to last years numbers with CARBS...
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