Ritter v4.0

I've seen their ads in Panorama for EFI/MFI bodies and their specs read well (to my layperson's eye)- are they any good?


Is anyone here using them- whats your experience?

TIA

Matt Romanowski

We are running them on a 3.8 RSR spec motor with Motronic and have had very good luck with them. Nicely made and fit well.

Ritter v4.0

Matt,

Thats why I'm asking. I have a 3.8 in my car and was entertaining the thought. What size are you using?
Works ok with Motronic- which DME- stock 3.6 or other? Who is doing your Motronic tuning?

Geoffrey

We have used them in the past before PMO sold them as a kit. They are made by TWM and work well, but are not ideal. Due to the fact that they are using the original Webber manifold design, the outside cylinders have a longer intake manifold length than the center one and it causes the engine to run differently between the cylinders. You can see this on an engine dyno with 6 EGT or 6 AFR sensors. The longer manifolds (1, 3, 4, 6) produce torque lower in the power band and therefore will run leaner than the center one at the higher RPMs. As long as you are aware of this and plan for it in your tuning, you will be fine. The other consideration is that there is a single throttle shaft through the three cylinders and if there is any height difference in your head/cylinder stack, the shaft will bind and not operate freely.

As a general statement, 48-50mm works well with the 3.8l engine. 52-54mm is too large.

You will need an altered Motronic system that can use TPS as the fuel metering channel to use ITBs, or you can simply convert to a MoTeC ECU.

Ritter v4.0

Noted- cheers.

The kit in their Pan ad (non-basic/expanded version) seems pretty inclusive- any thing else required?

Geoffrey

You'll need fuel injectors, fuel pressure regulator, fuel lines, intake air temp sensor and depending on chassis, throttle linkage modification.

Ritter v4.0

Gotcha. Thanks.

PedroNole

I run TWM in mine and the latest generation are a BIG step up from previous. I run DTA engine management and the tuning is still a little more art than science. I don't think it's an engine management issue, I just think that trying to mate advanced software with a mechanical butterfly system and the close but imprecise nature of the castings/fittings,etc is difficult. I have a dip in my hp/torque curve at a certain point that I can't get out. We've debated trying to get at it by having varying trumpet sizes but I haven't wanted to spend the money to hunt and peck if you know what I mean.

Ritter v4.0

You sound a little frustrated- understandably so. Still, have the overall gains been worth the effort, the dip notwithstanding?

KeithC2Turto

I think this is a Race Motronics system. Not the base system that comes on a 964/993.

There is somone that can convert your stock Motronic system to use a TPS and MAP set up so it will work with the ITBs. I think it is Prototec and it cost about $2k.

PedroNole

Yes, I'm very happy with the overall gains. That said, what I wouldn't trade for some of the torque that your 3.8L makes over mine.....

Steve Weiner-Rennsport Systems

Hi David,

For best performance, this works a LOT better: These are 46mm versions but we have 50mm ones, too.

PedroNole

Steve-

As always, very nice! Whose throttle bodies are those?

Geoffrey

I can Highly recommend the throttle bodies Steve showed in the picture, I have them on my engine although I have modified the overall stack length to work specificly with my engine design.

Changing the trumpet length will move the power up and down depending on the length. It does not generally reduce the dip you are experiencing. This dip is common with the PMO setup and can also be seen when using a weber carb. I believe it is due to the design of the manifold. Again, this setup is cost effective, but far from ideal.