The Forced Induction VR6 thread

[CrazyDave 0]

Always a fine line between coils working fine and blowing. How much dwell are you running Kev? I think you posted 2500uS on Vortex, which should have been fine, but if they are lower impedance then maybe thats a bit high. The general rule (which I'm sure you know) is enough to charge fully but not enough to cook them, too much dwell will heat them very quickly. Hence the stock pack needs a ballast resistor to limit the charge current.

 

Mmmm Rotrex! Nice kit Rob, sure you'll be pleased when you get that running :)

 

Marcus.... your in for a very big grin!!! 8)

[herisites 0]

Christ that thing looks exactly like a turbo!

 

That's one hefty oil cooler for it too. Nice job my man 8)

 

Yeah i showed my mate it and he was certain its a turbo :lol:

 

The charger is quite small so probably makes the oil cooler appear more hefty :lol:

 

Does anyone have an idea on how much traction oil im going to need to use for it? Its 100 euros per litre!! :shock: so i dont really want to have to buy more than a litre, coxy seems to think a litre will be enough for it.

[Kevin Bacon 5]

Dave, in the software I did indeed put 2500us, but Allan at DTA told me the dwell has it's own map, so I guess it's just a baseline, but I later discovered the MSDs (and also the stock pack) work better in multiples of 300us, so 2300 or 2600 worked better for some odd reason!

Does the stock pack have a ballast in it? I'm just running straight from the DTA to the coil posts. I think it has it's own current control built in though.

 

Rob, get a bit of oil analysed at a college lab mate. I bet it's only Olive oil or something :lol: No point paying 100 E a litre if it's something you can get off the shelf for pence. You know what companies are like with accessories, they whack up the prices deliberately cause you can't get it anywhere else....

[herisites 0]

Rob, get a bit of oil analysed at a college lab mate. I bet it's only Olive oil or something :lol: No point paying 100 E a litre if it's something you can get off the shelf for pence. You know what companies are like with accessories, they whack up the prices deliberately cause you can't get it anywhere else....

 

I tell you what it does feel like olive oil, sod it i will just use that! :lol:

 

Where the hell would i be able to get the oil tested???

[Kevin Bacon 5]

Dunno, wasn't being entirely serious :lol:

 

Getting stuff lab analysed would be pretty difficult I reckon, but if you know someone in a technical college....

[herisites 0]

Dunno, wasn't being entirely serious :lol:

 

Getting stuff lab analysed would be pretty difficult I reckon, but if you know someone in a technical college....

 

Ok i thought you were being serious :oops:

 

I dont know anyone that smart! I will have a word with a few guys who know their rotrex's and see if there's anywhere i can source some traction oil cheaper! Im sure there will be!

[marcus 0]

Are you sure its not a turbo :lol: ??

 

So where exactly in the bay is that going to be mounted then?

Do you have much more to get?

[Kevin Bacon 5]

Just brackets and boost pipes 'n' things!

[StormchargedVR6 0]

I do like that Rotrex charger :D , i know vince was mapping one this week. Interesting to know how he got on.

[herisites 0]

Are you sure its not a turbo :lol: ??

 

So where exactly in the bay is that going to be mounted then?

Do you have much more to get?

 

Yep definately not a turbo :lol:

 

It mounts on the side of the engine where the airbox would be, it mounts on a custom bracket and runs off the main pullies.

 

Here is a pic of Mr Fusions installed:

 

 

All i got from Coxy was the charger itself and its oil supply including oil cooler. I need to get the custom bracket, pullies (mine hasnt got aircon but it needs the aircon pulley to fit) and belts to actually fit it to the engine (from R-Tech in Denmark) and then i need to upgrade the injectors as i intend to run about 8 psi so will need bigger injectors (still looking into the saab black tops!), and then its just the piping for it and a cone filter really and then take it to Vince to map it all up :D so shouldnt take too long hopefully!

[herisites 0]

I do like that Rotrex charger :D , i know vince was mapping one this week. Interesting to know how he got on.

 

Thats good to hear, atleast now i know he has a bit more experience with the rotrex chargers as i believe Mr Fusions was the first he done? Im sure its not that much different to a vortech etc to map though.

[CrazyDave 0]

Dave, in the software I did indeed put 2500us, but Allan at DTA told me the dwell has it's own map, so I guess it's just a baseline, but I later discovered the MSDs (and also the stock pack) work better in multiples of 300us, so 2300 or 2600 worked better for some odd reason!

Does the stock pack have a ballast in it? I'm just running straight from the DTA to the coil posts. I think it has it's own current control built in though.

 

I don't think the stock pack does, but the Motronic dwell will be set just right for it anyway. The guys on vortex measured the pack impedance and ballasted the supply to cope with stock dwell (well thats what it looks like). Pretty sure the coil outputs in DTA are direct and the dwell takes care of not over charging the coils, unless it's set to high :)

 

Rotrex are a great charger, very reliable with minimal extra belt tension. I was very close to going this route myself, but went for turbo in the end 8)

 

The other thing you'll notice about Rotrexs' is they develope boost much earlier than a VF, the gearing is much higher to give boost lower down. Really quiet 8)

[herisites 0]

The other thing you'll notice about Rotrexs' is they develope boost much earlier than a VF, the gearing is much higher to give boost lower down. Really quiet 8)

 

Yeah Mr Fusions set up gave 5 psi as soon as he touched the throttle! :shock: Thats wheel spin city :lol: Im only going to be running 8 psi max though so hopefully mine wont be lighting up the tires toooo bad!

 

Also with the inlet pipe being 80mm and the outlet pipe being 50mm that helps with low down torque as well i believe!

 

I have read up about the rotrex alot when coxy's came up for sale as at first i thought they were only for serious power and was put off with the fact not many guys were running them as apposed to the vortechs which are as common as muck! But they are a very solid charger capable of some silly power in the future so i decided to go for it. I understand superchargers are never going to be as fast as turbos really but at the end of the day i wanted more power not stupid power and power that was usable throughout the rev range so a supercharger is perfect, also they cost less which helps!

[alex303 0]

The charger is quite small so probably makes the oil cooler appear more hefty :lol:

 

Does anyone have an idea on how much traction oil im going to need to use for it? Its 100 euros per litre!! :shock: so i dont really want to have to buy more than a litre, coxy seems to think a litre will be enough for it.

 

lovely & compact those Rotrex's though eah, smaller than the alternator!

 

Ian's probably right Rob, my kit came with 1litre of SX100 which at 80 euros plus VAT is'nt cheap but its better to run it on the correct stuff at the end of the day, the oil coolers a nice addition but not necessary until you go past 300bhp but certainly won't hurt it. That small black inline lump in your oil lines though is essential, its the primer for the oil system (did'nt get one with my charger when i picked it put unfortunatley and had to source elsewhere) the C30 series does'nt need it but our SP series chargers do. Am still trying to find the digital version of that SP series PDF manual on my bloody hard drive but if i can't i'll scan the print-out i've got already & pm it to you next week.

[herisites 0]

The charger is quite small so probably makes the oil cooler appear more hefty :lol:

 

Does anyone have an idea on how much traction oil im going to need to use for it? Its 100 euros per litre!! :shock: so i dont really want to have to buy more than a litre, coxy seems to think a litre will be enough for it.

 

lovely & compact those chargers though eah, smaller than the alternator!

 

Ian's probably right Rob, my kit came with 1litre of SX100 which at 80 euros plus VAT is'nt cheap but its better to run it on the correct stuff at the end of the day, the oil coolers a nice addition but not necessary until you go past 300bhp but certainly won't hurt it. That small black inline lump in your oil lines though is essential, its the primer for the oil system (did'nt get one with my charger when i picked it put unfortunatley and had to source elsewhere) the C30 series does'nt need it but our SP series chargers do. Am still trying to find the digital version of that SP series PDF manual on my bloody hard drive but if i can't i'll scan the print-out i've got already & pm it to you next week.

 

Ahh i was wondering what that was, im glad i got it then if its essential :lol:

 

Yeah that would be great mate if you can PM me a copy, would come in handy when fittin it.

[CrazyDave 0]

Rob. The power delivery should be smooth and progressive, all the way. Just might peak a little earlier than the VF. You'll love it! Loads of torque.

 

Done a few checks this morning with Motronic connected, standard injectors etc. With a scope on one of the coilpack trigger wires, the dwell is 6ms!!!!! No wonder MSD's burn out without a ballast resistor. It also confirmed my misfire which does exactly the same as megasquirt, timing light on the no.3 HT lead shows several missed sparks every now and again.

 

Also interesting to drive with Motronic on, it doesn't run lean at all (although only 50% throttle). But it doesn't like the dump valve. Everythings fine until you lift the throttle, the dump valve opens, lots of air rushes past the MAF and the fuel goes very rich, then cuts and shows a lean spike, then back to normal. Does run very very nice though.

 

The front and rear banks are timed differently for injection, scope shows a definate advance in triggering the rear banks that changes with engine speed. This is going to prove a problem for Megasquirt as it doesn't support sequential injector control and variable injection start. Like DTA, VEMS, Emerald do.

[craziscot 0]

Rob. The power delivery should be smooth and progressive, all the way. Just might peak a little earlier than the VF. You'll love it! Loads of torque.

 

You'll find it just keeps pulling, more like a turbo, on a steep almost linear curve until the engine rev limitor kicks in and spoils all the fun! :D The curve is very different to a Vortech curve.

 

I'll get my power graph scanned in and up on Monday or Tuesday when I can get at the works scanner.......

[StormchargedVR6 0]

Heres mine with 12psi making 329.9bhp , be nice to see a Rotrex graph.

 

329.9 BHP (Medium).jpg[/attachment:60bea]

[dukest 0]

Heres mine with 12psi making 329.9bhp , be nice to see a Rotrex graph.

 

show off! :D

 

Just wanted to say Shaun, I finally got to Vince on saturday morning on the way to the Scorcher and am very chuffed with the manifold! Just about resisted the tempting offers (from those more able than me) to have a go at fitting it there and then! Will let you know when its on though. Thanks again!

 

John

[KADVR6 0]

you should have taken me up on the offer of fitting the manifold John, i was in the mood for doing some manual work :)

 

karl

[StormchargedVR6 0]

Heres mine with 12psi making 329.9bhp , be nice to see a Rotrex graph.

 

show off! :D

 

Just wanted to say Shaun, I finally got to Vince on saturday morning on the way to the Scorcher and am very chuffed with the manifold! Just about resisted the tempting offers (from those more able than me) to have a go at fitting it there and then! Will let you know when its on though. Thanks again!

 

John

 

Sorry about the wait john, glad you finally got it. :D

[Kevin Bacon 5]

Also interesting to drive with Motronic on, it doesn't run lean at all (although only 50% throttle). But it doesn't like the dump valve. Everythings fine until you lift the throttle, the dump valve opens, lots of air rushes past the MAF and the fuel goes very rich, then cuts and shows a lean spike, then back to normal. Does run very very nice though.

 

Aye, it does run nice on Motronic because of the MAF and auto advance. It was the same with OBD2. It was super smooth and with the BEGI fuel riser you could floor it too. Obviously the Bosch ECU is trying to maintain 14.7:1 AF on boost under part throttle conditions, which isn't too clever, so you'd get a big shunt as the AF leaned and the MAF clipped and then it cleared and took off like a rocket. If you just floor it, it goes to the open loop map straight away and doesn't blip. A bigger MAF would housing would sort it.

I've got my 2D DTA map as good as OBD2 felt now and if I used MAP as load and seq injection for a full 3D map, it would be miles better than Motronic, but it's quite complicated :?

 

The front and rear banks are timed differently for injection, scope shows a definate advance in triggering the rear banks that changes with engine speed. This is going to prove a problem for Megasquirt as it doesn't support sequential injector control and variable injection start. Like DTA, VEMS, Emerald do.

 

For OBD1 aswell? Blimey. I thought only OBD2 timed the banks differently. Curiously, my front bank is slightly leaner than the rear bank, you'd expect it to be the other way round! One suggestion was try different grades of plug in each bank, but I've now put 8 grades in which seems to be helping.

A leaking manifold isn't helping either. Tom seems to have dissapeared from the face of the earth, so I'm faced with welding up his manifold (it's also developed a crack in the branches 5 & 6)) and machining it flat, or starting over with an ATP manifold, which will be a total pain in the butt as it means a change of downpipe and wastegate setup......but Pipewerx could prob do that in a day as they also sell the manifolds.

 

Will the squirt be getting a sequential add on at some point?

[CrazyDave 0]

Quite difficult to see the front to rear comparison on injector timing, so maybe my eyes are out of calibration! I only have a two channel scope and one of the traces needs to be VR sensor to get TDC.

 

The front cylinders being lean would make sense if it's the fuel being 'pulled from the walls' of the cylinder head. So longer tract = more fuel to the rear? Just an idea.

 

I'm a bit concerned about my manifold now? It's not blowing as far as I'm aware, or sooting as you describe, so fingers crossed. It's a big casting though so cracking might occur as it grows at a different rate to the head? Could you see it from the top / outside or just when stripped down?

 

Looks like I've reached the limit with the squirt, lack of sequential injection is starting the hinder my efforts so I'm looking into options. But for the moment I plan on running Motronic with a BEGI or similar rising rate and buffer the MAF signal through a DSP microcontroller linked to a MAP sensor. This will allow filtering of the throttle closing, manifold depression condition to get the fueling stable during shifts. ie trick it into getting a stable MAF output when the dump valve opens. And clamp the MAF during WOT.

 

May also be able to fiddle a little more fuel during part throttle by tricking the O2 probe during closed loop.

[marcus 0]

All this timing, fueling collaberation baffles me.

Respect to those attempting to conquer it.......i didnt have the nerve to. I just like the thought of making it the garages problem to correct. LOL....but, i'll probably still be posting up about running problems in a few weeks knowing my luck :lol:

[Kevin Bacon 5]

All this timing, fueling collaberation baffles me.

Respect to those attempting to conquer it

 

Tuners have had it their way for far too long.....keeping all this info close to their chests.... I for one (aswell as Dave I'm sure) aim to shoot off the padlock and bring it all out into the open, and hopefully, prove it's not that difficult to understand 8)

 

Dave, you have PM regarding the BEGI FMU.

 

Regarding the manifold crack, it *Might* be heat related, i.e. me not fuelling the motor rich enough. From what I've learned with the DTA, VRT's are no good at pretending to be economical by running 14.5 AFs on cruise and 13.5 - 13 on part throttle boost. So I've given it a very rich lambda target map to help reduce EGTs. I'm now 13.5 everywhere on part throttle, 13 to 12.5 on mid to 3/4 throttle and 12 to 11.5 on full throttle. It runs *significantly* better running this rich and I now understand why the Yanks always run their VRTs super rich.

I keep forgetting this is not a 4 pot motor and 14.7 is just not going to happen on a 3 litre 6 pot with a very quick spooling turbo :lol:

Anyway, keep an eye on your manifold. TBH, I can't see any soot around the crack, so I'm hoping it's just a slight casting defect, but I'm keeping my eye on it.

 

Keep me posted on your Stock + BEGI managment route as I'm not discounting going back to OBD2 either.....