Alex Wong1697456877 Posted December 24, 2000 Share Posted December 24, 2000 I was wondering if any of the Vx big guns out there had any pearls of wisdom about how to get close to 250BHP but still keep some drivability, whilst not needing to spend the earth to attain this. Beware : Low flying pigs imminent. Seriously though, I've had enough of these SLR's (and a certain Supersport blush.gif keeping up with me so it's time for more power!!! I had looked at the QED route but they reckoned only 235 BHP with Q450 cams and some porting. A Swindon stage 5 (aka JPE) head is another option (aggressive cams and lots of porting) but this is rumoured to be very peaky. I would like a broader power band to make driving in the wet less likely to enhance my gravel trap affinity reputation! smile.gif Any help or advice would be most welcomed. Also, which has a bigger influence on narrowing the power band? - cams / compression ratio / TB size / porting / valves etc. Alex Wong www.alexwong.net _________ / / ___ _/______ /_ ___ / (_) (_)/ /`-'/o/ _______ o/`-'/ / /// ( VDU7X ) / / /___/--_________/--/___/ Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted December 24, 2000 Share Posted December 24, 2000 Answer:---- Swallow your pride and fit a Minister tuned 'K'series R500 unit!!!!!!!!!!!!!!!!!!!!!!!! The words 'No' & 'Chance' keep coming to mind!! Link to comment Share on other sites More sharing options...
Powderpuff Posted December 24, 2000 Share Posted December 24, 2000 More likely b****r o*f wink.gif But then again maybe Alex will eventually see the light....nah teeth.gif Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 24, 2000 Author Share Posted December 24, 2000 An R500 unit........ if I had the money, I would buy an R500 and keep VDU, but I couldn't put a k-series in VDU! Next you'll be suggesting I paint it kawasaki green or something. It pains me just to think about it! Having said that, the R500 engine is the most perfect 7 engine I've ever tried, but it's a little on the expensive side! AND, it doesn't look as good under the bonnet tongue.gif Some people just don't understand....... teeth.gif Alex Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 24, 2000 Author Share Posted December 24, 2000 So Albert, you're a K-series man.... and you're starting to sound like someone I know...... Hmmm..... Link to comment Share on other sites More sharing options...
Andrew Dent Posted December 25, 2000 Share Posted December 25, 2000 Alex, First of all Merry Xmas form the 2 of us and the car. You never know what Santa mic=ght bring!! Andrew Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted December 25, 2000 Share Posted December 25, 2000 << And it doesn't look good under the bonnet>> Alex. I had you down as one who drove not just admired the view! I do think your "I hate 'K's" position is sounding now in a somewhat weakened state! Will wonders never cease? It must be Christmas!!! Link to comment Share on other sites More sharing options...
DaveK Posted December 25, 2000 Share Posted December 25, 2000 Alex as a fellow vauxhall 16v devotee i can give you as much advise as you want as i have currently spent more on engine conversions than cars? there is a big difference between real bhp and quoted bhp ,but as long as your engine is built to a matched spec then mapped correctly it doesn,t matter what the figures are as long as it is performing at 100% If you want to give me a call on 07947 816175 after boxing day i can perhaps advise you on some more suitable mods cheers Dave Link to comment Share on other sites More sharing options...
Swiss_Tony Posted December 25, 2000 Share Posted December 25, 2000 Alex Stick with a proper engine! I am looking to up-grade my vx soon. SBD reckon 208 bhp with their throttle body kit alone. This seems very optamistic to me. I am unable to see how 30 bhp can be gained by just doing this. Has anyone had experience of this? James Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted December 25, 2000 Share Posted December 25, 2000 Derek K. At least you have the right surname initial letter!!!!!!!!!! Link to comment Share on other sites More sharing options...
elie boone Posted December 25, 2000 Share Posted December 25, 2000 First of all a Merry Christmas to all on the net. Alex, is yuor engine a 2 ltr are is it larger ? i think you can bore and stroke it up to 2.2 or 2.3 witch give you more torque for the same horspower, if it whas an 8 valve you can bore and stroke it to 2.7 and it will rev to 7000 with truckloades of torque (Mantzel in Germany build that engine for us, 222ps and did never breakdown) Link to comment Share on other sites More sharing options...
captain chaos Posted December 25, 2000 Share Posted December 25, 2000 Alex, All these supposed 'K' and R500 devotees are just fashion victims. It's all been said before about tradition etc... but these lads are just caught in the hype of the latest 'hip' offering which the magazines are talking up. It's all pub talk. Picture the scene down the local Dog & Duck..."Here look lads, Car mag recon my R500 is the b*ll**ks, am I hard or what!" I've seen it all with the R1 boys on bikes and at the moment it's Saturday Nite 'K' Fever in Caterhams. Get your motor sorted and prove a point for all us Vx fans at Curborough! Blows smoke from the end of his pistol and retires to the saloon. Edited by - captain chaos on 25 Dec 2000 20:01:10 Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 25, 2000 Author Share Posted December 25, 2000 Current engine spec. 45mm Throttle bodies DTA 3D ignition Dedicated map by John Noble (Rolling road) Q420 cams with verniers Solid lifters Standard valves Omega 86mm "flat-top" pistons Standard con-rods Race rod bolts Standard crank lightened flywheel Current realistic power approx 200BHP I know that BHP figures are misleading and my car feels faster than a 218 Swindon unit and only a bit slower than a Swindon 235 unit. It feels a long way away from a Swindon 250 unit or a QED 250 BHP unit, all of which I've tried in 7's. I'm reluctant to bore it out further as I'm keen to keep it below 2000cc. At the moment, the engine has a fantastic power band that makes it the most drivable engine I've tried but it lacks top end power. 1/4 mile times are usually in the region of 13.2s which is slower than a SLR I ran against which managed 12.9s so 200BHP is probably about right. The car feels strained at higher revs and I feel ready for more power now but it is difficult to know which way to go. Alex Alex Wong www.alexwong.net _________ / / ___ _/______ /_ ___ / (_) (_)/ /`-'/o/ _______ o/`-'/ / /// ( VDU7X ) \/ / /___/--_________/--/___/ Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 25, 2000 Author Share Posted December 25, 2000 James, 208BHP on TB's alone sounds very optimistic to me. Alex Edited by - Alex Wong on 25 Dec 2000 22:06:55 Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 25, 2000 Author Share Posted December 25, 2000 Dave K, Thanks! I'll be in touch. Alex Alex Wong www.alexwong.net _________ / / ___ _/______ /_ ___ / (_) (_)/ /`-'/o/ _______ o/`-'/ / /// ( VDU7X ) \/ / /___/--_________/--/___/ Link to comment Share on other sites More sharing options...
StewartG Posted December 26, 2000 Share Posted December 26, 2000 Alex, I wonder if you really are noticing the difference in power between the various engines you've tried. I suspect that everything else being equal, weight, gearing, tyres, seats etc the difference that 17bhp makes between one swindon engine and another is going to be negligible. It's a bit like audio amplifiers you need a whopping great increase in power before it sounds any louder. I wonder if chasing outright horsepower is just specs-manship. In real road or even track situations the grip and handling are always the limiting factor. If I where looking to upgrade my Vx engine I'd be after a better throttle response from a lightened, balanced and blueprinted unit with perhaps better breathing at high revs I'd also like a faster changing gearbox to complement the throttle response. I would be wary I didn't end up with a unit which performed on the dyno but was a pig to drive. As far as losing out to SLRs goes it's not the lack of power thats the problem it's their lack of weight and no increase in BHP will solve this it'll just make your tyres spin more. Link to comment Share on other sites More sharing options...
Swiss_Tony Posted December 26, 2000 Share Posted December 26, 2000 How about a bit of BD power ali block etc! Or ali block vx! James Edited by - James on 26 Dec 2000 10:34:19 Link to comment Share on other sites More sharing options...
elie boone Posted December 26, 2000 Share Posted December 26, 2000 James,a alloy BD block alone is +/- 2000£ Alex, if you do not want to increase the capacety of your engine and get better lap times, then maybe better brakes or shorter diff ratio may be the answer and it is cheaper than a tuned engine. Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 26, 2000 Author Share Posted December 26, 2000 If I wanted to decrease my lap times, the best way to do it would be to practice more! Competition is just for fun and in any case, I haven't lost to an SLR in a sprint yet although I think it's imminent. I did lose to one in a drag race. I just want more power. It's not a matter of specsmanship. If you sit in an R500 or a JPE and open that throttle, there is a distinct adrenaline rush and I kinda like that teeth.gif Of course an increase in power can overcome a weight disadvantage. Otherwise my car would be slower than a graduate car! It's not that easy to spin wheels apart from off the line. Bear in mind that the Vx car is not that much heavier than a k-series car. The best way to improve the throttle response would be to go throttle body injection, lighten the flywheel and lighten the crank/rods/pistons. Three of which I've done already and I already use a close ratio box with quickshift lever (best upgrade so far). I just want to experience more power! It will corrupt of course! teeth.gif Alex Edited by - Alex Wong on 26 Dec 2000 22:10:00 Link to comment Share on other sites More sharing options...
Powderpuff Posted December 26, 2000 Share Posted December 26, 2000 Alex, did I say I was a K series man, I don't remember doing so, its just that I accept k is the future and Vx should be put in a museum wink.gif Al Link to comment Share on other sites More sharing options...
Swiss_Tony Posted December 26, 2000 Share Posted December 26, 2000 Al I suppose all the BEST things are put in museums Just to remind us what a real engine is all about TORQUE! James (running for cover) Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted December 26, 2000 Author Share Posted December 26, 2000 Al, I've only let one K car humiliate me and as I told Powder Boy, he won't do it again! Look at it this way, if the Vx engine ever makes it into a museum, it'll be in a BTCC car. If the K series ever does, it'll be in a metro. smile.gif Alex Edited by - Alex Wong on 26 Dec 2000 22:21:15 Link to comment Share on other sites More sharing options...
Swiss_Tony Posted December 26, 2000 Share Posted December 26, 2000 K-series engines make very good paper weights! (if a little light) If they are that good what happened to Rover? James (proud vx owner) Link to comment Share on other sites More sharing options...
Paul Ranson Posted December 27, 2000 Share Posted December 27, 2000 The key to engine mods isn't the headline power figure, that's just the baseline, the key is balance. So you could persuade your engine to peak at 250BHP with some wild cams and crossed fingers but it wouldn't necessarily be very nice to drive. OTOH do a balanced conversion between enhanced flow, wilder cams, a stronger bottom end (as necessary...) and lightened flywheel/clutch and happiness will ensue. A Seven is very light in real terms, and it doesn't have to hillstart 4 up with a caravan on the back, so you can afford to have relatively peaky engine. It will require an amount of finesse in the wet, but that's part of the challenge, attention spent on engine mapping other than at WOT helps here. I'm not familiar with the potential of the nominally standard Vauxhall engine, but I do know that if you put the 295BHP Swindon from my Pilbeam into a Caterham it would be very driveable, even in the wet, you just wouldn't (ever) be at full throttle.... I think you either need to become an expert or choose an engine builder and take their advice. It would be too easy to end up with a curate's egg of an engine. I'm bothered that the QED and SBD 'kit' approach de-emphasises the head/valve/breathing part of the equation and retains the hydraulic followers. Perhaps there's too much stress on the bolt-on and DIY aspects to produce a balanced solution, one that's only as peaky as it need be. Paul Link to comment Share on other sites More sharing options...
Marius Posted December 27, 2000 Share Posted December 27, 2000 Alex, I just got my VX16v rebuild by a german engine-tuner (RISSE) and I´m very lucky with it (so far, fingers crossed). I´ve done to nearly 100% the same modifications as you already have but a lot of efforts went into the cylinder-head. I think this should be the next step for you (just my opinion though). I got mine gas-flowed, 304° cams, solid lifters, raised compression (12.3:1), adjustable vernier pulleys etc... Realistic engine-pros reckon that a proper gas-flowed 16v Vauxhall-head can add around 10BHP and is also the base for further tuning. 304° might sound too hot but the engine is very driveable. Indeed I still run it in so I have to cope with around 4.500rpm max right now. I only had to raise the idle-speed to around 1.400rpm, not especially for the cams but the solid lifters which do not like too low revs. My advise: 1) get that head properly done (different cams??) 2) strenghtend con-rods 3) proper dry-sump An engine like yours with the above mods should be able to reach about 250BHP. In fact mine does with throttle-bodies. Have fun ! Marius Link to comment Share on other sites More sharing options...
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