DIY OBD-1 Varioram Conversion Step by Step (More or less)
#76
Advanced
Join Date: Dec 2007
Location: The Netherlands
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi Joe,
Yes I do mean the actuators, mine do not cycle with the key in position number II...they are "activated" and once the car is started the actuators return to their normal positions. When I drive the car I do feel and hear the VRAM working, maybe i should fit some sort of test lights to the solenoids, just to make sure that they are activated by the ECU. Or when doing it realy fancy, mount two LED`s in the lower switch panel, in front of the gearstick.
Yes I do mean the actuators, mine do not cycle with the key in position number II...they are "activated" and once the car is started the actuators return to their normal positions. When I drive the car I do feel and hear the VRAM working, maybe i should fit some sort of test lights to the solenoids, just to make sure that they are activated by the ECU. Or when doing it realy fancy, mount two LED`s in the lower switch panel, in front of the gearstick.
#77
Banned
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi Rutger,
I apologize for initially misunderstanding your question. The actuators should operate just as you describe: key to position 2 - actuators open, turn the key off or start the car and the actuators return to their original positions.
Congratulations, it sounds like you installation was a success!
Enjoy,
Joe
I apologize for initially misunderstanding your question. The actuators should operate just as you describe: key to position 2 - actuators open, turn the key off or start the car and the actuators return to their original positions.
Congratulations, it sounds like you installation was a success!
Enjoy,
Joe
#79
Rennlist Member
Join Date: Jul 2003
Location: Peachtree City, Ga
Posts: 1,951
Likes: 0
Received 64 Likes
on
54 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Dave - It is not about adding juice but were it puts it. The varioram system does not increase juice it redistributes the juice. What the V-ram does is increase the HP/Torques at the lower end. The V-ram adds approx a 20% to 30% increase in HP and Torques around 2800 to 3700 RPM over a non V-ram system - but after that the curves pretty much follow the standard line engine HP and torque path.
#80
Advanced
Join Date: Dec 2007
Location: The Netherlands
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi,
After al my questions about installing a Varioram inlet manifold on a non-Varioram 993 I thought it would make sense the put the charts of my dyno-run on this forum. The first chart is the one where the 993 still has its orignal inlet manifold fitted with a 200-cell sportscat (Gert Carnewal). Top figures are:
281.1 HP and 343,9 Nm
The second chart shows the gains over the firts chart. The 993 is now fitted with a cone filter and the same 200-cell sportscat. Top figures are:
287.8 HP and 351.0 Nm
So regarding the top figures, not really worth the money and time, but the improvement in the lower RPM range is, at a certain point I gained almost 40 HP..
My 993 is a USA spec car, so it has the "long" gearbox, with this modification the car feals as it should have felt. I can only think how it would drive with the "short"gearbox...
So, bottom line is it worth all the work? I think it is, the most difficult task was to get all the parts. I was lucky that I found a gentleman who sold me the Vario-ram inlet manifold together with the correct ECU and would take my old manifold as a part exchange. If you have any questions please let me know.
Last but not least, a special thanks to Joe for answering all my questions!
Regards,
Rutger
After al my questions about installing a Varioram inlet manifold on a non-Varioram 993 I thought it would make sense the put the charts of my dyno-run on this forum. The first chart is the one where the 993 still has its orignal inlet manifold fitted with a 200-cell sportscat (Gert Carnewal). Top figures are:
281.1 HP and 343,9 Nm
The second chart shows the gains over the firts chart. The 993 is now fitted with a cone filter and the same 200-cell sportscat. Top figures are:
287.8 HP and 351.0 Nm
So regarding the top figures, not really worth the money and time, but the improvement in the lower RPM range is, at a certain point I gained almost 40 HP..
My 993 is a USA spec car, so it has the "long" gearbox, with this modification the car feals as it should have felt. I can only think how it would drive with the "short"gearbox...
So, bottom line is it worth all the work? I think it is, the most difficult task was to get all the parts. I was lucky that I found a gentleman who sold me the Vario-ram inlet manifold together with the correct ECU and would take my old manifold as a part exchange. If you have any questions please let me know.
Last but not least, a special thanks to Joe for answering all my questions!
Regards,
Rutger
#81
Rennlist Member
Join Date: Jul 2003
Location: Peachtree City, Ga
Posts: 1,951
Likes: 0
Received 64 Likes
on
54 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Interesting looking at your dyno sheet - I installed the Varioram on my 964, and have a similar dyno sheet - and it looks like the results are pretty much the same in areas of increase. Obviously, the numbers are different overall - but the plots on the chart are very close. I have since made a few other mod's , but have not had further dyno runs.
I am really amazed at the significant increase in the low end torque and the noticeable seat of pants feel at around 3000 RPM .
I am really amazed at the significant increase in the low end torque and the noticeable seat of pants feel at around 3000 RPM .
#82
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Rutger,
In post number 3 you mentioned that one must buy the two sizes of hoses and the rubber connectors. Specifically which two rubber connectors? I am supposing part number 30 (993 110 601 40) but from the PET it seems I would only need one of these.
Also, did you stay with the non-vram venturis or by the other one, that is, pos 23 part# 067133 753 A vs 078 133 753?
From the research I have done the vacuum systems are otherwise identical beween the non-vram and the vram. Did you reach the same conclusion?
Karl
In post number 3 you mentioned that one must buy the two sizes of hoses and the rubber connectors. Specifically which two rubber connectors? I am supposing part number 30 (993 110 601 40) but from the PET it seems I would only need one of these.
Also, did you stay with the non-vram venturis or by the other one, that is, pos 23 part# 067133 753 A vs 078 133 753?
From the research I have done the vacuum systems are otherwise identical beween the non-vram and the vram. Did you reach the same conclusion?
Karl
#83
Advanced
Join Date: Dec 2007
Location: The Netherlands
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Karl,
If you mean post #3, that is not my post, it is Joe`s .
But looking at the pictures I do remember I had to change one of the oil breathing hoses.
As per the venturis, I had to get different ones since my V-ram manifold came of a Carrera 4, there is a difference between the vacuum system of a Carrera 4 and 2.
Regards,
Rutger
If you mean post #3, that is not my post, it is Joe`s .
But looking at the pictures I do remember I had to change one of the oil breathing hoses.
As per the venturis, I had to get different ones since my V-ram manifold came of a Carrera 4, there is a difference between the vacuum system of a Carrera 4 and 2.
Regards,
Rutger
#85
Banned
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Rutger,
In post number 3 you mentioned that one must buy the two sizes of hoses and the rubber connectors. Specifically which two rubber connectors? I am supposing part number 30 (993 110 601 40) but from the PET it seems I would only need one of these.
Also, did you stay with the non-vram venturis or by the other one, that is, pos 23 part# 067133 753 A vs 078 133 753?
From the research I have done the vacuum systems are otherwise identical beween the non-vram and the vram. Did you reach the same conclusion?
Karl
In post number 3 you mentioned that one must buy the two sizes of hoses and the rubber connectors. Specifically which two rubber connectors? I am supposing part number 30 (993 110 601 40) but from the PET it seems I would only need one of these.
Also, did you stay with the non-vram venturis or by the other one, that is, pos 23 part# 067133 753 A vs 078 133 753?
From the research I have done the vacuum systems are otherwise identical beween the non-vram and the vram. Did you reach the same conclusion?
Karl
Hope this helps
#87
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Joe,
Another question as I am onto the wiring part of the conversion. Why did you run wires from the ecu for the resonance flap and varioram solenoids instead of just moving the pins in the 21 pin connector in the engine compartment? I know its to each thier own kinda thing, but I am just worried that I am missing something obvious or not so obvious.
I dont get too many chances to work on my car so this project is taking a long time.
Cheers,
Karl
Another question as I am onto the wiring part of the conversion. Why did you run wires from the ecu for the resonance flap and varioram solenoids instead of just moving the pins in the 21 pin connector in the engine compartment? I know its to each thier own kinda thing, but I am just worried that I am missing something obvious or not so obvious.
I dont get too many chances to work on my car so this project is taking a long time.
Cheers,
Karl
#88
Banned
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi Karl,
I apologize for the slow response. My reading of the wiring diagram indicates that leads #1 and #32 do not run to the x60 (21 pin) connector. This is probably why I ran the wires directly from the ECU.
Hope this helps,
Joe
I apologize for the slow response. My reading of the wiring diagram indicates that leads #1 and #32 do not run to the x60 (21 pin) connector. This is probably why I ran the wires directly from the ECU.
Hope this helps,
Joe
#89
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Indeed it does. I wound up building a new harness from the old resonance flapper back to the fuse box for the varioram solenoids, and disconnecting the SAI relay and rewiring it for the old resonance solenoid in the fuse box. I am loath to cut into an existing and oem harness (though I have a spare one) so I built harnesses to make the conversion completely reversible in the unlikely event I have to go back to non-varioram. My objective was to get as close to stock ROW varioram as I could. One would have to do some in depth sleuthing to discriminate my work from a stock ROW varioram. Well accept for the fact that it now has a varioram intake instead of a resonance flap intake.
Once again, thanks for your documentation. This would have been a far more difficult project without your help. On the shoulders giants as they say.
Karl
Once again, thanks for your documentation. This would have been a far more difficult project without your help. On the shoulders giants as they say.
Karl