255psi Vs 270psi F328

Hi Rod,

I have a US version originaly with 255 psi. As far as I know there were 2 version with 255 psi, the US and the Swiss. Both of them are Catalized version of the 328.

The cat system of the 328 was rather restrictive, the 2 headers exhaust combines into a single pipe that then converges into a single CAT, and from there to the muffler. The total power loss were those 16 psi.

To return one of these CAT 328 to European standar it is not complicated, but it will be expensive, te total exhaust pipes, headers and muffler alone will be somethink like 7.000€. But to complytly match the European version you will have to change also the 2 CPUs and posibly touch the ignition and Air injection systems.

However some say The CAT isself was responsible of the lose of 10 of the 16 Psi. If that is tru, replacing the CAT with a testpipe will put the car in 265 psi.

Also you can replace the filter with a K&N one. There is plenty of discussion in this board about if changing a filter makes a difference or not. However I think the bst is a test, you can look at this test from Rob Lay's car at a Dyno, with and without a K&N filter:

Rob Lay's 1986 328 GTS

Readings at the rear wheel in the Dyno:
- With stock air filter - 218.8 hp 186.0 torque (lb/ft)
- With K&N air filter - 228.4 hp 190.4 torque (lb/ft)

At the flywheel, with 16% correction loss
- With stock air filter - 260.5 hp 221.4 torque (lb/ft)
- With K&N air filter - 271.9 hp 226.7 torque (lb/ft)

If you add both the car should be in the neigburhood of the 280 psi, theoricaly. I have replaced the CAT wit a Stebro Resonator test pipe, and the filter with a K&N filter and I certaily noticed a significant improvment, specially at high revs. Of course this can ve done to the standard non-cat European version too.

However, if you are in Europe, go the easy way an get a standard European car with 271 bhp, repairing the CAT version cars is always more expensive.

I hope this helps.

- Julio.

 

Brilliant explanation by Julio!

Go for the Euro 328!

Ton

 

Holly Molly!!! I did misstype there some words ... sorry!

Next time, I will review the message before posting it.

- Julio.

 

Yes, I have driven both. The 255 psi version feels a bit less powerful. It is most noticeable accelerating from the line, although this coud be because of the gear ratios of my US version, and not the power output itself. But the 328 engine does not have too much torque, so the diminish torque in the 255 version should be noticiable from stop.

I am not sure but I think I remember reading in R&T that acceleration in the US version 0 to 60 mph was 6.2 s , that is half a second slower than a regular 328. But I might be wrong.

What I have not done is driving a 255 psi CH (Swiss) version, which has the same gear ratios thatn the European version. And I have not driven a 328 either since I installed the test pipe and the K&N filter in mine, so I can't comapare the after mods sensations.

But as I said, unless there is a huge difference in price between the 255 and the 271 psi versions that you are looking at, there is no reason to get a 255 psi version.

I have it just because I was living in the USA when I got it, and I brought it back to Europe with me. If I would had bought it here, I would had purchased the standard 271 psi European version.

- Julio.

 

I like the 308 QV lines as much as the 328.

I think there is another member of this chat from Scotland. He used to have a 328 Azzuro (beautiful blue color). He sold it recently and got a yellow 355.

His name at the forum is 'matkat'. You could send him a Private Message, he might be able help you on your search!

- Julio.