The Forced Induction VR6 thread

[coullstar 0]

I dont like looking at that....

[boost monkey 0]

Forgive me if i missed something, but what are the main diffs between Jammin and Haywire's VRTs? I always thought they were pretty similar builds.

[Kevin Bacon 5]

Forgive me if i missed something, but what are the main diffs between Jammin and Haywire's VRTs?

 

The only major differences are gearing and turbo size, and he runs more boost than me too :D

 

Essentially, I have a laggier turbo and shorter gearing and Ben has a quicker spooling turbo and taller gearing.

 

What's happened here, imo, is Ben's turbo / mapping delivered too much torque too soon and in 5th gear, the car probably didn't have enough momentum to hitch up it's skirt and blast down the road, and as he has a diff, uprated clutch and decent tyres, what's the next weakest link in the chain? The gears :D

 

Compared to mine with shorter gearing and more lag, the car already has momentum behind it before the torque kicks in, so regular skirt hitching and blasting has been reliable for 4 years. The shorter gearing also makes up for the deficit in spool time and the car is easier for the engine to move. I ran 13psi for nearly 2 years, which isn't far off Ben's boost and it loved that aswell!

 

All VRT owners fear the gearbox letting go and Ben was just unlucky. It's always a case of when, not if! Most people lose 3rd first but it's good to see Ben's been enjoying some motorway blasting too! That's where all the tailgating knobbers tend to hang out, so VRTs are a good weapon there.

[boost monkey 0]

I like it :D great comparison Kev, thanks.

 

Jammin I'm not surprised that there's more than one cog that let go. After all, as you said they have probably got weaker over time, and as they're all made of the same material (not actually sure what that is though, some kind of steel?) then if one lets go then it's meshing partner probably will to, or at least take some damage.

 

What's the plan now, new gearbox?

[Kevin Bacon 5]

Yeah some kind of tough steel with hardended teeth. It's because they're helical cut, they can't take half as much torque as straight cut, but straight cut chips are too noisy and clunky for the road, so we have to use the crinkle cut ones instead.

 

I've heard you can make them a lot stronger with cryo treatment though, but it's feckin expensive and time consuming.

 

Gemini Transmissions made a semi-helical crinkle cut kit, which offered the best of both worlds, but they're expensive and rare.

 

Which leaves the 02M the only sensible and cost effective option really. That or just limiting the boost to what the gearbox can handle :wink:

[coullstar 0]

02M it is then.

[vr6boy 0]

I havent been round here in quite a while due to being out of work and no money :(

 

But I have a straight cut SQS racing SSS gearset for the road with a peloquin atb diff kit with a 3.6fd ,

 

The engine should be going in next week and the downpipe should be getting modified monday or tuesday

 

 

Its quite a while coming and should have been on the road over a year ago but things never go according to plan

 

There is a bit of a build thread here http://www.ukpassats.co.uk/phpbb/viewtopic.php?f=5&t=19536

[KADVR6 0]

you guys seen this gearbox on ed38, the guy lives down the road from me so i can collect/send it (if he still has it??)

[Kevin Bacon 5]

I havent been round here in quite a while due to being out of work and no money :(

 

But I have a straight cut SQS racing SSS gearset for the road with a peloquin atb diff kit with a 3.6fd ,

 

The engine should be going in next week and the downpipe should be getting modified monday or tuesday

 

 

Its quite a while coming and should have been on the road over a year ago but things never go according to plan

 

There is a bit of a build thread here http://www.ukpassats.co.uk/phpbb/viewtopic.php?f=5&t=19536

 

He lives :D Wondered where'd you'd gone buddy!

 

Looking very nice there fella, I like your smoothing on the compressor elbow!

 

Based on my experiences of that ATP manifold and the ARP studs, you might want to go back to the OE studs, washers and copper nuts. They allow some movement in the iron. The ARPs do not and I had a stud pull out of the head, had to helicoil it :( Check out my gallery thread.

[vr6boy 0]

He he he yeah still here Kev :lol:

 

First time I was over with Billy boy he showed me that turbo that someone had done and changed his mind and had it up for sale and I took it off his hands saved me having to get one done

 

Engine hopefully going in next weekend into my B3 Passat not a corrado I know but .....

 

WOW not so good with the ARP ex m studs must change them over so cheers for the heads up again kev :clap: will have a looksie now

[jamminvr6storm 0]

I like it :D great comparison Kev, thanks.

 

Jammin I'm not surprised that there's more than one cog that let go. After all, as you said they have probably got weaker over time, and as they're all made of the same material (not actually sure what that is though, some kind of steel?) then if one lets go then it's meshing partner probably will to, or at least take some damage.

 

What's the plan now, new gearbox?

 

Yeah, as a temporary measure I have a Golf VR box and will be using the gearset from that and my Wavetrak diff. I will look into some more options for the longer term.

 

Yeah some kind of tough steel with hardended teeth. It's because they're helical cut, they can't take half as much torque as straight cut, but straight cut chips are too noisy and clunky for the road, so we have to use the crinkle cut ones instead.

 

I've heard you can make them a lot stronger with cryo treatment though, but it's feckin expensive and time consuming.

 

Gemini Transmissions made a semi-helical crinkle cut kit, which offered the best of both worlds, but they're expensive and rare.

 

Which leaves the 02M the only sensible and cost effective option really. That or just limiting the boost to what the gearbox can handle :wink:

 

I read up on cryogenically freezing stuff when I was building the engine, its being done on pistons rods and cranks, im not sure how sucessful it is.

 

Looking into custom gearboxes / gearsets, I spoke to Elite Transmittions who were recommended by a friend with a 500hp fiesta cosworth. They will provide a custom gearset with one-off ratios (mmm 190mph top end), shot peened for strength.... but the downside is its £4000+ VAT.... and no warranty :shock:

[coullstar 0]

Fook that, just stock pile VR boxe's. Ive just remembered reading an artilce a while back in Performance Bike where the guy has his R1 gearbox refurbed by this company who were using some process that strengthened the teeth. For the life of me I cannot remember what they did but Im sure it was like shot peening.

[Kevin Bacon 5]

Looking into custom gearboxes / gearsets, I spoke to Elite Transmittions who were recommended by a friend with a 500hp fiesta cosworth. They will provide a custom gearset with one-off ratios (mmm 190mph top end), shot peened for strength.... but the downside is its £4000+ VAT.... and no warranty :shock:

 

Eurospec's version of the 6 speed Gemini kit, and already cyro treated. Great value at £2500 for a complete built up box if you ask me. Includes uprated 1st and 2nd as well :D

 

http://eurospecsport.com/products/trans ... ssions.htm

[boost monkey 0]

Isn't that the cryo treatment that Kev mentioned before?

 

Edit: beaten to it by the man himself.

[Kevin Bacon 5]

Fook that, just stock pile VR boxe's. Ive just remembered reading an artilce a while back in Performance Bike where the guy has his R1 gearbox refurbed by this company who were using some process that strengthened the teath. For the life of me I cannot remember what they did but Im sure it was like shot peening.

 

Fook that as well! :D When a box goes in, it stays in! Sod replacing them every month, I'd rather do without so much power :lol:

 

Isn't shot peening like 1000s of little hammer blows? It's interesting how metal changes from being whacked and frozen. I wish I understood why it works!

[boost monkey 0]

I can find you diagrams and engineering nonsense :D

[coullstar 0]

Work hardening the surface is it not? Theres also ION nitriding.

[jamminvr6storm 0]

you guys seen this gearbox on ed38, the guy lives down the road from me so i can collect/send it (if he still has it??)

 

What box is this Karl ?

[coullstar 0]

Where can you buy the sump oil line adaptor for the return line? Current one has a fitting welded on that the return line makes up to, Ive got a baffled sump to fit. Either that or is there anywhere to buy baffles for my current sump.

[Kevin Bacon 5]

Speedflow sell most things oil plumbing related.

 

Need to see a picture of it really as it could be anything.

 

I return my oil via the block and use a standard -10 to 1/2" NPT fitting

 

Maybe do the same and fit the MK5 R32 sump / pump?

[coullstar 0]

After my run on the RR on Sat I was trying to see how the other turbo guys on here had faired but not many figures banded about to compare against so I thought I about a quick poll for info. I'll start:

 

Brief engine spec 2.8l, Schimmel 263 cams, 8.5:1 Comp, FMIC, short runner, 3in DP + system with CAT

Turbo Garrett GT3582r (1bar)

Power 359bhp

Torque 315ft-lbs

[Kevin Bacon 5]

Wossner 8.5:1 83mm pistons (2937cc)

Schimmel Head

Schimmel 263 cams

Schimmel Air-Water intercooler

Schimmel short runner

3" DP -> 3" ATP Cat -> 2.5" Techtonics

GT3582R 0.82

 

All I have are the plots from the dyno day in 2008 but nothing's really changed since then. 392bhp and 337lb ft @ 11psi.

[jamminvr6storm 0]

SPEC:

Wiseco 9:1 83mm pistons (2937cc)

THS Rods

Big Valve Head

Schimmel 263 cams

Forge FMIC

Schimmel short runner

3" Exhaust

Larger TB

4" Air Intake

GT3076

525cc Injectors

Emerald ECU

 

Power

Map 1 - 326.9bhp @ 7psi

 

 

Map 2 - 382.1bhp @ 10psi

 

 

Map 3 - 540bhp

[coullstar 0]

Wow, some impressive figures from fairly low boost levels. What were you guys ATW figures?

[Kevin Bacon 5]

350 whp for mine.....