bassam

I will be replacing my 1989 engine with a 993 varioram, my question is regarding the oil lines and filters. do I run the car with 2 oil filters (original and the one in the engine)? if yes will this slow circulation? if one only is needed which one do I delete? Thank's.

Steve Weiner-Rennsport Systems

Hi Bassam,

JMHO, but I always retain both oil filters on these engines.

Its VERY nice to filter the oil both on the pressure and scavenge side, especially if something goes wrong. There is no restriction in oiling as long as you use the right filters.

bassam

thank you Steve, like always, a wealth of info. I bought this motor from an older gentleman that loves Porsches, his plan was to put it in his 1970 tub. the story behind the engine is that it was removed from a new 1997 993 with 26 miles on it! that car was transformed into a gt2 race car by Brumos Porsche as factory stopped exporting them to the U.S. how true I dont know, but the engine looks new. The guy powdercoated engine tin, replace a fuel line with stainless steel braided hose and added a vacuum reservoir. due to health issues, engine sat in his garage for the past few years. With the engine came a g5020 2 = LSD, when I forget how much I spent will send you the LSD for that awsome rebuild of yours.

Steve Weiner-Rennsport Systems

Send me the DME and I'll make it "better",....

bassam

will drop it it the car this weekend, make sure it runs fine and will do.

herman maire

Steve,

I have 2 Vram engines that I have for my projects. What do you do to the ECU?
Thanks

Steve Weiner-Rennsport Systems

Reprogram the fueling and timing maps for better throttle response and more mid-range torque.

Your ECU's must either be a 0.261.204.376 or 0.261.204.649 to do this.

Gus

You also have to figure out how you are going to control the 3 resonance flaps on the Vram -
You can use the single circuit to control all or get a RPM activated control switchs to add - or get a whole new ECU -

bassam

I got a euro 993 v-ram DME for this engine, previous owner connected a vacuum reservoir as well, would that solve the flaps control? not too familiar with resonance flaps.

Gus

IF you have the Vram ECu and the wiring all should be OK -
There are 3 resonance flaps in the Vram 2 upper an 1 lower - The 2 upper activate at teh same time (5200 RPM) the lower activates at 5800 RPM. All are controlled by the ECU and activated through a electric solenoid that opens a vacuum line to operate the flaps at the respective RPM. If you were using the standard 964 ECU you would have to resolve how to activate.

Gus

OH!! One other bit of info that you need to know - Your (Stock ECU) Vram should, on start up, run a teest on the operation of the system - So if you have a friend start the car - you should be able to see the flap solenoids cycle through operation at idle. Then they return to normal position and operation. This is a standard procedure for the 993 ECU.

bassam

thank you for the info. I have a 1995 dme but the harness connects to the vram, could that be possible? (can a nonvario dme operate vario?) inside the dme there is a cyntex chip that has vario written on it. Thank's again.

Gus

What is the DME out of - Did it come from a 993 with Vram ?/ The stock 964 ECU only has one resonance flap control - this is a minor problem and can be fixed - The question is going to be does the harness and 95 DEm allow you to control the activation of the three resonance flaps ( two at the same time )> From where did the wiring harness an d the DME come?? Year is not important as long as it is from a car with a Vram (model is).

Bill Verburg

A) Vibrating tube induction

If the gap (5) between sliding section (4) and central
intake distributor (6) is closed, the intake system is a
single-chamber vibrating tube induction system. Intake
air flows from the central intake distributor via vibrating
tubes designed for maximum torque to the cylinders.

B) Resonance induction

If the sliding sections (4) open, switching the system
from vibrating tube to resonance induction, the air flow
branches downstream from the air mass sensor (1).
One branch is connected to the central intake distributor
(6) of the single-chambersystem and one to the resonance
system (7) below the intake distributor.

From the central intake distributor, part of the intake air
flows through the intake pipe extensions, which act as
resonance tubes, directly to the intake funnels of the
short vibrating tubes and to the cylinders. The main intake
air stream flows via the second throttle flap and
the first large resonance tube of the resonance system
(7) to the resonance chambers. The resonance induction
system optimizes air flow to the short vibrating tubes.

C) Resonance induction with open tuning flap

The tuning flap (3) is installed in the second large resonance
tube. Initially, the tuning flap is closed. At a defined
enginespeed (5920 rpm), the tuning flap is opened,
increasing the flow area between the resonance chambers.
Air now flows to the resonance chambers via all
the connecting pipes.

Switch over conditions for intake pipe extensions
and tuning flap

1. When the ignition is switched on, the DME control
unit activates the solenoid valves. If the engine is
started, the intake pipe extensions and the tuning flap
are operated. When the engine has run up to idle
speed, the signal to the solenoid valves is deactivated
and the intake pipe extensions and tuning flap
are set to their basic positions.
2. If the engine speed reaches 5160 rpm and the
throttle valve is at least 50° open, the DME control
unit transmits an electrical signal to the solenoid
valves of the intake pipe extensions and the extensions
are operated, switching the intake system over
from vibrating tube to resonance induction.
3. If the engine speed is higher than 5920 rpm and the
throttle valve is more than 50° open, the DME control
unit opens the tuning flap, increasing the resonance
tube cross section.

Bill Verburg

Yes, the '95 US DME and all the RoW vram DME's are interchangeable the chip inside the DME must be vram specific, hopefully the original owner swapped in a compatible chip.

all '95 and all RoW '96-97 normally aspirated 993 are OBD1 and use the same 55 pin DME and 55 pin engine to DME harness. some minor rewiring is required to change from non vram to vram config and again the chip is specific to the engine intake setup.