Bradan twin turbo 355 build.

Lol! So many F355 turbo experts giving BRANDON advice . And theres me thinking there were only a few turbo charged 355s out there

 

Turbocharging is turbocharging. While I may not be a respected Ferrari expert I spent years building and tuning boosted motors on my own dyno. I respect the fact that this is somewhat uncharted territory with regard to the Ferrari, it's not with regard to turbocharging and making power. The Miata (which I use as an example) has the nearly the same size bore (and in general will have similar detonation characteristics under boost). Bore size is critical to determining how much compression and boost you can get away with at a given octane.

A Ferrari uses an internal combustion engine that is subject to the same physics and thermodynamics as any other engine. I know it seems like heresy that what might apply to a Miata or a Honda could possibly apply to the Ferrari, but it does.

I get what you are saying, but even at part throttle, it has been my experience that freeing up the exhaust side makes sense, even with the GT28RS. No doubt the GT28RS is capable of making the power, but even at part throttle I did not find the transient response sufficiently improved to matter. I believe reason may be is that you are still (especially in the case of the GT28RS) spinning that big compressor. The issue could be the miss match between the turbine and the compressor. The bigger turbine seems to be more efficient at getting the compressor to respond once the boost threshold is met. Now while I do know a thing or two about turbocharging, I am not an engineer by trade, so if you want a mathematical or theoretical explanation of why i observed this, I won't be able to provide it. Bottom line is that there is no wrong answer, all boost is good. I will admit to some personal bias against the GT25/28 series of turbo's, I never did like them.

 

Yea, chill out. I was having a joke

 

It's all good.

 

Dear Braden,

I'm excited to watch this Ferrari F355 turn into a beast. I thank you for entertaining me with pictures and work on the car.

I look forward to looking at more of your posts.

Thank you again.


Sincerely,

Schaf97

 

Pictures are beautiful!!!

Got to love this work horse of a motor your staring with

 

This thread is almost to good to be true.

Q1: Is the intent to create a turn key F355 turbo kit for sale as a package?

Q2: Is the intent for the kit to be used with a stock engine? As in, stock compression, stock rods, stock pistons, ect, or would the block need to be "built" for the kit to safely work?

 

This is going to be a great project. I really enjoyed the Gallardo conversion. What 0 - 60 and quarter mile times are you expecting?



Jimmy

 

Never underestimate the market for the same hardware tuned to 7PSI on a stock engine.

 

Anyone want to guess what the compression ratio of the stock pistons would be if the lip were machined down to the height of the dome?

 

8 to 1? which is close to what they should be for a Turbo engine...

 

You may be close on the compression (maybe 8.5-1?) but I disagree that it's what it should be.

Personally I wouldn't drop the compression more than half a point, max.

 

My S2000 loved 7 psi from it's centrifugal SC and it has 11:1 CR. It made 308rwhp from 2.0L. Understanding these are not the same cars their engines are somewhat similar, high-revving small displacement/high CR so I would expect them to respond similarly when boosted.


Hopefully I will be able to show what a TT 'stock' F355 engine can do at some point in the future............


Awesome project, I will stay tuned.

Rob

 

I am very interested to see what the end configuration is. 11 to 1 is very high for a turbo engine using 90's fuel deliver style (not direct injection). My guess would be that 9.5 - 1 or so would be the sweet spot for the amount of boost, type of fuel delivery, strength of enternals, and typer of EMS (assuming Motec or comperable).

Pushing the limit on an engine that cost 25-40k to rebuild is just not a good idea, especially when the performance will be mind blowing without pushing it.

 

I think 500 crank hp would be easily attainable with properly sized injectors/fuel pump/octane with 6-7 psi without overly stressing the engine. You may actually be able to short-shift and have a more reliable engine while making 500hp.

 

Keeping higher compression is not about pushing the limits but maximizing driveability.

With the bore size, cam timing and overall design of this engine I would consider even 10.0-1 ultra conservative.

Just my opinion, I run that or more on V8's with twice the displacement.

 

I enjoy these threads more than viewing a Ferrari in a showroom. If I had the money & the confidence in myself, I would disassemble & reassemble a Ferrari every year. Reminds me of assembling car models as a child.