tuning

[andyhudson 10]

Well I've done some searching but was hoping for abit more information and ideas. I'm look at tuning mods on my standard vr6. Firstly ill look at going exhaust, exhaust manifold, bmc induction, 263 cams, port and polish (doing this myself so will try do a guid if it goes well) and may be bigger valves. But then what next, I'm after ideas. That don't involve FI, I don't fancy ITB's as it means stand alone management, or paying the earth for a schrick manifold. Bit new to tuning so not sure on some things, will bigger valves mean bigger injectors?

 

I am a faby welder so I can make modify stuff. I was thinking of taking a stock inlet manifold and cutting it and improving the flow or making a new one completely with a different design. I've tried to find pictures of custom inlets but most stuff seems to just be for FI.

 

Fire away with ideas please and if there is stuff I can make and works then I may make a few more. As ill be making some stainless tank straps next and eventually stainless brackets ect for in engine bay.

[Metallix 10]

Save money, keep the standard airbox. BMC carbon thingy for £££ = what +/- 1 bhp?

 

I saw a 2.8 VR6 at a recent dyno day do 200bhp / 210lbft

(ok this is in a Golf Mk3, not a 2.9 Corrado)

 

Standard airbox (albeit drilled)

Standard camshafts

Standard exhaust manifold, downpipe, catalyst

2nd hand cat back stainless system

Corrado 2.9 VR6 intake manifold adapted to use the 2.8 throttle & idle control.

DIY ported head

Remapped ECU.

 

For comparison, a healthy standard 2.8 VR6 Mk3 Golf was present and this made 183bhp / 187 lbft

 

If this was done on a 2.9, I think you could easily get 210 bhp / 220 lbft, maybe more.

 

For comparison, a healthy standard 2.9 VR6 Corrado was present and this made 195bhp / 201 lbft

 

 

Interesting to also note that the bottom end on the modified 2.8 has done over 170,000 miles.

[andyhudson 10]

Surely a bmc will help though when aiming for as near as I can get to 250bhp.

[Metallix 10]

Well I would say leave it till last.

 

It's an expensive part for small if any gain vs. standard airbox with a brand new paper filter or aftermarket panel filter.

 

It sounds & looks cool yes, but focus on the items that with give bigger improvements first.

 

Is there a specific use in mind / reason for 250 bhp target? (No torque figure target?)

[andyhudson 10]

thats just a general figure i have in mind, and obviously i want more torque as well. i know that 220ish is generally easily got with cams i trying to think past that to what would be next. im after a fast road car basically, i dont want to throw money at FI as its alot of work and expensive. i basically want to make the car so it pulls instantly from bottom end and is a fast back road driver. but i like to try rengineering or engineer stuff myself so thats why im thinking of doing a custom inlet manifold and port and polishing head my self.

[VW_OwneR_85 1]

thats just a general figure i have in mind, and obviously i want more torque as well. i basically want to make the car so it pulls instantly from bottom end and is a fast back road driver. but i like to try rengineering or engineer stuff myself so thats why im thinking of doing a custom inlet manifold and port and polishing head my self.

 

judgeing by the sounds of your requirements what you need to do is a 24v 2.8 or 3.2 conversion.im happy as larry with my 2.8 24v and mine hasnt even had a remap and its not going to either ;)

[andyhudson 10]

judgeing by the sounds of your requirements what you need to do is a 24v 2.8 or 3.2 conversion.im happy as larry with my 2.8 24v and mine hasnt even had a remap and its not going to either ;)

 

no no no, i dont want to do a conversion. i want to stick with the original engine, im going for oem look. i want my car to look like it could be a standard car but tweaked to be better in all the small places which an enthusiast would notice. and as part of that look i want to stay with the same idea in the engine bay, which may lead to a slightly cleaned up bay eventually. so i suppose on that note a bmc wouldnt look all that good.

 

ive noticed there just doesnt seem to be all that much available or done naturally aspirated. there seems to be very few options. inlet manifolds for example, every one seems to just accept they have to buy a schlrik manifold no ones really seems to have modified one or made one from scratch. im trying to gauge if theres ideas like that, that people have and see if i can put some of them into practice.

[VW_OwneR_85 1]

thats fair enough but iv seen loads of pics of 24v conversions which look more oem then most 12v vr6s out there today , dont forget its the newer updated vr6 so its still oem territory, its not like you would be converting it to a tdi , yea your right a bmc on that note wouldnt look good neither would chopping up the inlet manifold ;)

Edited May 8, 2013 by VW_OwneR_85

[andyhudson 10]

ino what your saying but i like the idea of keeping the original engine and working at that. well it depends how you chop it, and to what standard and finish you leave it at, or a new one from scratch. my trade is welding and fabricating and theres a few toys at work i can take advantage of, laser cutting, milling turning, all types of welding, press brakes, polishing equipment, rollers, blasting (both dry and wet) all sorts

[seanl82 23]

It would cost less to swap it out for a 24v including a remap, than it would cost you attempting to gain as much from a standard VR tbh. The inlet is just a piece of metal, by going larger you will only peak at slightly more than standard, before it tails off. By going larger you will also move the power band higher up the rev range anyway, defeating what you want to achieve. I don't really know anything about the schrick tbh, but its vvt so I'm guessing its mechanical/electrical, so trying to replicate that yourself will probably cost you just as much in time and meterials. If it was a viable option to highly tune a standard engine for reasonable money, it would have been done by someone in the last 20 or so years the 2.9 vr6 has been in existance tbh mate.

[andyhudson 10]

so what do you think is a realistic achievable figure then without going to made?

[dannyboy 0]

i agree with sean on this,porting only helps high revs plus you may end up with a very unhappy engine in the low to mid rev range due to the mixture not burning efficently to to the slow down in velocity entering the combustion chamber. getting 250 bhp from the vr6 is unrealistic without spending lots of money on increased displacement,injectors and ecu to match.Ill probably stand corrected but im sure the r32 3.2 is 240 bhp standard which would be a easier and cheaper way of acheiving 250.Lots of people focus on bhp when they should consider torque more.torque is more fun than bhp.

[andyhudson 10]

Not being filled with confidence here. Looks like I'm going to have to have a real think. Yeah ino torque is as important if not more important in some cases. Interesting about the porting and polishing, if I was to just do exhaust side then that will then help retain some low down power?

[VW_OwneR_85 1]

have a look here http://www.vr6oc.com/e107_plugins/forum/forum_viewforum.php?120

 

 

the rolling road thread at the top,

just a quick look through it ,the most impressive N/A is vr6pete

 

218 BHP @ 6685

 

262.4 Nm @ 3825

 

2.9 low comp bottom end, schrick big valve head, schrick VGI, Dastek, Miltek, BMC... but still running my old map with the 2.8 and 268 cams.

Edited May 8, 2013 by VW_OwneR_85

[Stonejag 10]

Interesting you want to keep the 12v engine as I'm doing something similar! My motivation is more to work with what's already there though, engine swaps are outside the realm of OEM+ in my mind.

 

Start with the exhaust - if you're good at fabricating then you could knock up a six-branch replacement for the stock cast manifolds and downpipe quite easily. It's worth attempting to match the lengths as the front cylinders have a longer exhaust tract - not sure if the usual suspects (Dubpower / Raceland) have done this, or even if it's possible in the available space. The rest of the exhaust system can be widened to 2.5" / 3" and you can lose the cat or replace it with a high-flow one.

 

I say go for the BMC CDA because it's cool and I've got one ;) I was replacing a dodgy cone filter so only used the stock airbox for a short time but it felt a lot more 'muted' compared to the CDA. Hopefully you'll like the boy-racer noise! Probably worth leaving the rest of the inlet alone. VSR/Schrick manifolds have two different-length inlet paths which the changeover controlled by a vacuum-operated 'flap' - so not that complicated, but not something you'd really want to develop from scratch.

 

Replacing the inlet air temperature sensor with the one from a 1.8t is supposed to give a couple of free horses. link

 

Cams are a safe bet - 263s get the best reviews around here, but I think Autotech did some 262s which will be very similar. When you take the head off you may find enough corrosion on the base that it will need welding up - then once it's welded and needs skimming you could consider larger valves. 2mm oversize (42mm inlet, 36mm exhaust) are as big as you can go as the seats touch in the middle! Don't think many here have done that though - you could try a search for "big valve head".

 

If you're feeling flush you could bore out to a larger displacement (stock is 82.5mm pistons, a few places make larger ones), or go for a longer stroke crank. Both of these are scary money! Turbo and supercharging make big numbers but also at a high price.

 

With a big exhaust and some cams you'll probably be 70% of the way to perfection while only spending 20% of the money. Don't go too wild :)

 

Stone

Edited May 8, 2013 by Stonejag

[Metallix 10]

have a look here http://www.vr6oc.com/e107_plugins/forum/forum_viewforum.php?120

 

 

the rolling road thread at the top,

just a quick look through it ,the most impressive N/A is vr6pete

 

218 BHP @ 6685

 

262.4 Nm @ 3825

 

2.9 low comp bottom end, schrick big valve head, schrick VGI, Dastek, Miltek, BMC... but still running my old map with the 2.8 and 268 cams.

 

Though 262.4 Nm = 193.5 lbft, from a 2.9

 

The 2.8 I mentioned made 210 lbft on a dyno-dynamics, which are known to be "tough love" and not optimistic.

without the extra 100cc, the bigger valves, the switchable intake manifold, the uprated cams, and the expensive carbon air filter. ;)

[Stonejag 10]

Have a read of this - but bear in mind it's written for AAA motors mot ABV so some of it is irrelevant!

 

http://forums.motivemag.com/showthread.php?4761622

[andyhudson 10]

Interesting you want to keep the 12v engine as I'm doing something similar! My motivation is more to work with what's already there though, engine swaps are outside the realm of OEM+ in my mind.

 

Start with the exhaust - if you're good at fabricating then you could knock up a six-branch replacement for the stock cast manifolds and downpipe quite easily. It's worth attempting to match the lengths as the front cylinders have a longer exhaust tract - not sure if the usual suspects (Dubpower / Raceland) have done this, or even if it's possible in the available space. The rest of the exhaust system can be widened to 2.5" / 3" and you can lose the cat or replace it with a high-flow one.

 

I say go for the BMC CDA because it's cool and I've got one ;) I was replacing a dodgy cone filter so only used the stock airbox for a short time but it felt a lot more 'muted' compared to the CDA. Hopefully you'll like the boy-racer noise! Probably worth leaving the rest of the inlet alone. VSR/Schrick manifolds have two different-length inlet paths which the changeover controlled by a vacuum-operated 'flap' - so not that complicated, but not something you'd really want to develop from scratch.

 

Replacing the inlet air temperature sensor with the one from a 1.8t is supposed to give a couple of free horses. link

 

Cams are a safe bet - 263s get the best reviews around here, but I think Autotech did some 262s which will be very similar. When you take the head off you may find enough corrosion on the base that it will need welding up - then once it's welded and needs skimming you could consider larger valves. 2mm oversize (42mm inlet, 36mm exhaust) are as big as you can go as the seats touch in the middle! Don't think many here have done that though - you could try a search for "big valve head".

 

If you're feeling flush you could bore out to a larger displacement (stock is 82.5mm pistons, a few places make larger ones), or go for a longer stroke crank. Both of these are scary money! Turbo and supercharging make big numbers but also at a high price.

 

With a big exhaust and some cams you'll probably be 70% of the way to perfection while only spending 20% of the money. Don't go too wild :)

 

Stone

 

thats a real interesting point you've made there about the exhaust manifold, and if people like raceland have taken into account the different lenghts with in the head.

 

cheers for all the links and info i think im going to have a trawl through it all and start bit by bit. think ill be sticking with the 12v though. if i do a conversion then it will a 20vt so theres more tuning options, but i doubt i will be.

 

---------- Post added at 5:56 PM ---------- Previous post was at 5:55 PM ----------

 

Interesting you want to keep the 12v engine as I'm doing something similar! My motivation is more to work with what's already there though, engine swaps are outside the realm of OEM+ in my mind.

 

Start with the exhaust - if you're good at fabricating then you could knock up a six-branch replacement for the stock cast manifolds and downpipe quite easily. It's worth attempting to match the lengths as the front cylinders have a longer exhaust tract - not sure if the usual suspects (Dubpower / Raceland) have done this, or even if it's possible in the available space. The rest of the exhaust system can be widened to 2.5" / 3" and you can lose the cat or replace it with a high-flow one.

 

I say go for the BMC CDA because it's cool and I've got one ;) I was replacing a dodgy cone filter so only used the stock airbox for a short time but it felt a lot more 'muted' compared to the CDA. Hopefully you'll like the boy-racer noise! Probably worth leaving the rest of the inlet alone. VSR/Schrick manifolds have two different-length inlet paths which the changeover controlled by a vacuum-operated 'flap' - so not that complicated, but not something you'd really want to develop from scratch.

 

Replacing the inlet air temperature sensor with the one from a 1.8t is supposed to give a couple of free horses. link

 

Cams are a safe bet - 263s get the best reviews around here, but I think Autotech did some 262s which will be very similar. When you take the head off you may find enough corrosion on the base that it will need welding up - then once it's welded and needs skimming you could consider larger valves. 2mm oversize (42mm inlet, 36mm exhaust) are as big as you can go as the seats touch in the middle! Don't think many here have done that though - you could try a search for "big valve head".

 

If you're feeling flush you could bore out to a larger displacement (stock is 82.5mm pistons, a few places make larger ones), or go for a longer stroke crank. Both of these are scary money! Turbo and supercharging make big numbers but also at a high price.

 

With a big exhaust and some cams you'll probably be 70% of the way to perfection while only spending 20% of the money. Don't go too wild :)

 

Stone

 

thats a real interesting point you've made there about the exhaust manifold, and if people like raceland have taken into account the different lenghts with in the head.

 

cheers for all the links and info i think im going to have a trawl through it all and start bit by bit. think ill be sticking with the 12v though. if i do a conversion then it will a 20vt so theres more tuning options, but i doubt i will be.

[Stonejag 10]

Here's a pic of a Raceland one - looks like they did match port lengths as the pipes differ alternately (far left, cylinder 1, has a short exhaust tract in the head, and that matches with the longer pipe on the manifold)

 

Good practice for a bit of stainless fabrication, mind! :)

 

Stone

Edited May 9, 2013 by Stonejag

[aide 0]

a few years ago there was a guy on here (bananawhip) who took the vr6 n/a nearly as far as you can without losing base idle, i think he topped out at 240bhp and similar lb/ft, eventually he went forced induction :) to be fair he did say he missed the na approach though.

[VR6Pete 0]

My last VR6 engine built by stealth was rolling 221BHP.

 

Was a beast in my golf mk2 shell :)

[andyhudson 10]

My last VR6 engine built by stealth was rolling 221BHP.

 

Was a beast in my golf mk2 shell :)

What was the spec on the engine? And was it a 2.8 or 2.9?

[VAG-hag 0]

Mine made 221 on the rollers at stealth with 263s and map. Nothing else :)

[andyhudson 10]

So 240bhp and a similar torque figure should be a good figure to aim for. And then ill proberly assess it from there. What ill look to do then is exhaust manifold, decat and single box exhaust system, port and polish exhaust side, cams, on the inlet manifold there's a restriction up near TB on under side cut and plate that for better flow and may be the spark plug holes, lighten fly wheel if it can be done without being ruff. Stainless elbow in inlet from maf to give better flow and looks good. I'm sure I've missed something I was going to do. If I get board after all that in a few years then ill look at super charged

[g0ldf1ng3r 13]

Mine made 221 on the rollers at stealth with 263s and map. Nothing else :)

 

Mmmmmm thats a nice figure VAG-hag! Very interesting that you got that figure with just the cams map!

 

I am in discussion with stealth & planning on top end rebuild & 263's & a few other bits but im in a quandry at present as Im unsure whether to invest in a new exhaust first.......& the fact that the vortex solution im looking at is coming in at £1100!!!

Edited May 10, 2013 by g0ldf1ng3r