hey guys n girls, im looking to put a set of cams in my mk2vr6 just wondered what profile was best to get, cheers for any info darren
I think one of the best value cams at the moment has to be the Autotech 262. Schimmel 263s are very good cams too. I did a group buy on a ~ 60 sets of those a few years ago and everyone was happy with the results. Some guys saw well over 20hp gains on stock engines (inc exhaust and filter). Stealth Racing have the dyno plots. They're both 115 Deg Lobe centre, virtually the same duration and ~ 11mm lift. The more detailed stuff you will need to email them for. Then there's the Schrick 268s but their OE quality comes with an OE price tag to match. They do rob a little torque from the bottom end though, so many people partner them with a Schrick or VSR (if you can find one).
thanks for the info guys, i must say friend of mine has the schrick 268's we went to vw action and both went up the strip together it semt he had a better top end than me from the start it looked like i was pulling away at the start on the vids but it was neck and neck all the way up, i havent really looked at the market for the cams and was thinking of ringing vince at stealth for the advice, he did my map and was really impressed with it, im also going to be having the cylinder head ported and polished thinking of bigger inlet valves also, whats your opinions on this mod? cheers for the help guys
Yeah that's the often the case. People complain of a loss of torque low down from fitting cams, but as your experiment demonstrated, there's rarely even a car's length difference in it when it comes to full bore standing start acceleration. No one likes power that runs out too quick, so cams are a great mod for more top end pull Yes I fitted larger valves (Ferrea) to my VR6 head and with the cams it makes a nice difference. One thing the 12V head needs is a lot more flow!!
nice one mate what sort of power gains did u see when you did the work to yours, im also going to be putting the v5 gearbox on with the lower final drive, not a fan of the really long gearing on the vr, it was my daily but is undergoing major work gonna be doing a fw track days hopefully next year
"Power gains" very relative. With cams on the VR6 engine, you tend to shift the torque to the right of the X axis to then occur at near 5500rpm as per 16v. Currently most VR6 engines with factory cams peak torque at ~4200rpm and rapidly run out of puff after 5800rpm. Mapping can remove some of the over fuelling that influences this effect and increase torque though it still does not shift by many rpm, say 100-300rpm to the right. With an already optimised std engine, Cams will tend to reduce the torque in the lower WOT range as the peak shifts right at 5500rpm and then drop off at ~6400rpm or so. "V5" 3.9 FD will help to negate the reduced clutch torque from the engine with cams and the fact that the engine can now produce usable torque to 7000rpm means you can increase the rev limiter to 7200 rpm and not really lose any top end. It is a modification I am thinking about for my own "ankor". I will also add while WOT runs will show deltas in torque and power profiles on these engines with cams, the low down response often goes unnoticed and not properly mapped. This does take time on road to get right. With the older ECUs M2.9 prettry easyish and the later M3.8.1 more involved.
ok toyotec i kinda understand what ure saying but my brain has just fryed its self ill admit to anyone im not a very technical person im more of a , if it dont work ill hit it with a hammer kinda guy , this is why i work on trucks, ive had my map done by stealth racing, they raised the rev limiter for me to 7200rpm so i have that. im thinking of goin 268's and fit the v5 box so i shouldnt really feel the torque loss hopefully
ok toyotec i kinda understand what ure saying but my brain has just fryed its self ill admit to anyone im not a very technical person im more of a , if it dont work ill hit it with a hammer kinda guy , this is why i work on trucks, ive had my map done by stealth racing, they raised the rev limiter for me to 7200rpm so i have that. im thinking of goin 268's and fit the v5 box so i shouldnt really feel the torque loss hopefully
For the cam upgrade you would require more than just a 7200rev limit in the calibration file, which on standard hardware is pointless.
is that so i get the full benefit from the cam? and also is this why between mine and my friends vr there is not alot of diffrence? and are you saying i will be better off staying with the standard cam? cheers
Hard to say for your application mate because it was done on my turbo engine, which also had a short runner, which affects things still further Bottom line though:- An extra 50hp was found just by bolting on the head with larger valves and the cams. Same map, same everything. Anything you do to improve flow will help you make more power, it's a simple fact. Physics 101. more in = more out Have a chat with Vince and ask to see 'Vag-Hag's Corrado before-after plots with the Schimmel 263 cams. His made more power and torque everywhere in the rev range. The torque curve was exactly the same shape as stock, only fattened up. Some people will argue against that until they're blue in the face, but you can't dispute the physical evidence of a dyno run. Agreed on the VR6 gearing. It's inherent torque shyness doesn't lend itself well to leggy gearing. I use the 3.64 final drive in mine from the G60. The 3.94 is a little too short for my tastes but it will certainly make the car a lot more accelerative.
Yes the cam, all things being equal will allow improved breathing at higher rpm allowing you to increase your rev limit where the engine will still be making usable torque. You already have this set high, but on std parts will have no benefit. I have played around with the limit on my own car and if anything the engine makes less torque at 7200rpm than it would at 2000rpm WOT i.e shift up!! With the recalibration improvments that have been done to the car the rev limit is set at ~6900rpm. Recalibration means the baseline on the vehicle was 178bhp@5700rpm and 182lbft@4200rpm and now the same engine can achieve 190bhp+@5900rpm and 195lbft@4500rpm as tested at Garage Streamline on their modern Dyno Dynamics 450DS unit. I have also mapped in quick response mapped part load/ off WOT areas. The engine is a std 160K miler. The package of cam, 3.6/3.9FD and a proper recalibration w/increased limit should make for quick responding engine. As to how much "brake" the cam/cal mod would make to the engine I would not like to speculate on specific measured performance numbers or deltas/gains as they can be misleading and varied depending on where the vehicle is tested. The difference between your friends VR and yours could mean anything really.
Well first of all I'm goin to say thankyou to both of u for ure input on this, as the info u have given me is awesome, Ill give vince a call see what he says then look into it further, then when I eventually get all the parts the fun will start, Thanks again for taking the time guys
ive just been scouring google for plots on NA motors and it seems the drop off after 5.5krpm is practically free-fall and reving beyond krpm only worse from your experience turboing the ABF eddie, how would a VR on OE cams respond to a turbo? would you get a similar free fall drop off? im considering alternative cams to extend the rev band those extra few hundred rpm
ABF engine and methods to modify/add forced induction, are in its own category. Regarding turbocharging an AAA/ABV motor on OE cams? From what I have seen, mapped/driven a VR6T, depending on the engine speed the turbo achieves stable boost, the WOT plot from this point will imitate a torque plot similar to a NASP engine in shape. Just shape though as you can imagine the torque will be increased significantly over a NASP engine.
yes, thats what im trying to figure out. im trying to figure out that with a large blower, will you end up with a small band of usable torque with OE cams if they drop off after 5.5k if you change the cams, the engine will have a longer rev band but youd be unlikely to utilise 7krpm+ on a regular basis i cant find practically any plots of boosted VR6s on OE cams to see how the torque responds after 5k and i need to decide whether to factor it into the budget
You are being vague with "large blower" and "small band of usable torque" Do not understand if that is a question or if you are answering yourself My description was based on a few of these that I am not allowed to share.
im being vague with the blower because i simply dont know much about it, other than its a cheapo gt35 clone, so a real unknown unfortunately but if it starts making boost at 3.5k and its tailing off at 5.5k, then you only really have 2k based on your description of the engines with oe cams and boost then i think ill need to spec alternative cams
