Guest MK1gaz Posted March 17, 2008 Report Posted March 17, 2008 I had my engine checked over today as it started fouling the plugs and making my eyes water when i drove it !!!!!!!! . Chris traced the fault to the throttle position sensor nearly falling off (still at least my alternator and starter motor stayed put on the M25 !!!!!!! ) Anyway power is back up now with the air filter in the skip to 215 bhp and it's much nicer to drive . We haven't bothered moving the cams again yet due to me being too tight too pay for the extra mapping time this would create plus my £30 axle won't like it !!!!!!!!!
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 We also done a power run with the exhaust off (like the chaps at the drag strip do) and it lost 10 bhp !!!!!!! So it seems that leaving bits on has some advantages after all
bortaf Posted March 18, 2008 Report Posted March 18, 2008 Is that the vibration you was getting shook it loose? found out what it is yet or is the alt ok now?
over_head_cam Posted March 18, 2008 Report Posted March 18, 2008 Good power gaz. For those intersted you can find the same information here: http://www.oldskoolford.co.uk/phpBB2/vi ... &start=405
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 Is that the vibration you was getting shook it loose?found out what it is yet or is the alt ok now? Yes mate the vibrations now gone , it was caused by the propshaft going out of balance . It's certainly much better at motorway speeds now with the prop sorted , much more comfy .
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 I was wondering if anyone else has tested their engine on a dyno with the exhaust off ?
Admin Mk2Jo Posted March 18, 2008 Admin Report Posted March 18, 2008 Nice Gaz .... see you at Shakespeare County Raceway on the 5th/6th April then
Mk 1 Mark Posted March 18, 2008 Report Posted March 18, 2008 Loads more there somewhere Gaz. . . .Get your hand in your pocket Glad its getting where you want it
Toby Posted March 18, 2008 Report Posted March 18, 2008 I was wondering if anyone else has tested their engine on a dyno with the exhaust off ? No Sanspeed wont have it cos of his neighbours What happened to your fueling / mixture? Could you get the power back by putting that right?
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 The fueling and mixture was ok on full throttle at high revs with the pipe off . It sounded good as well apart from nearly blowing the wall behind the car to bits !!!!!!!! . It lost power though that's for certain
sambo Posted March 18, 2008 Report Posted March 18, 2008 Awesome Gaz. You must be chuffed. So, is there more to come with more mapping etc then? how much more ya think?
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 Yes i'm very pleased with how the car goes at present sambo . The mappings about right now so i just need the engine builder to swing the cams next to see what happens to the power curve . The problem is this fooooks up some of the mapping . I will get it done this year sometime once i can get myself , the engine man and the dyno all together at the same time for testing . I may try a 4 into 1 manifold later as well to see what happens as this will give me more power over 7200 revs . The engine can go to 9000 rpm so worth a look i reckon , i will lose bottom end power though but it depends on how much and i'll never know unless i get one and try it . As for power readings then it's hard to say as little things can make a big difference , i would love to hit 200bhp at the wheels one day on this dyno
4parajon Posted March 18, 2008 Report Posted March 18, 2008 Yes i'm very pleased with how the car goes at present sambo . If it was me I'd be happy with that mate
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 I'm well pleased with it Jon but interested to see what happens with the cams moved and maybe another exhaust . I gonna try it and see later
Toby Posted March 18, 2008 Report Posted March 18, 2008 Did I see on another post you had already tried to swing the cam timing (perhaps on the IAS post)? You have to try all the combinations of exhausts, but usually, the experienced builder will point you in the right direction with your combination of parts, as he's probably tried most combinations before. Imagine the number of combinations and variables though, cam choice, cam timing, exhaust lengths (primary, secondary, 4-2-1, 4-1, carb (throttle body) and any combination of the above sizes all requiring the right map (jetting). This is where going to an expensive experienced builder will save you money in the long run......and why they're not usually too forthcoming if you're not their customer. It's cost them time and money for their knowledge
sambo Posted March 18, 2008 Report Posted March 18, 2008 Wont you end up with a 'peaky' beast of an engine then Gaz? with the 4 into 1 etc. Carefull not to make it 'uncomforable' in traffic! 200 bhp @ the wheels will be awesome mate! Good luck!!
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 Did I see on another post you had already tried to swing the cam timing (perhaps on the IAS post)? the IAS thread . We moved the inlet cam 2mm clockwise in Nov 07 and it made an extra 15 bhp . We haven't moved it anymore or moved the exhaust one yet because we're worried about possible valve to piston contact . I looked at lots of graphs from some top notch race 4 pots that have been down there and most of them only gain over mine at 7000+ revs . When i bought my manifold they said it would limit the power over 7200 revs so i'm interested to try a 4 into 1 set up just to see what happens . You don't know until you try but your right about the endless combinations etc
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 Wont you end up with a 'peaky' beast of an engine then Gaz? with the 4 into 1 etc. Carefull not to make it 'uncomforable' in traffic! 200 bhp @ the wheels will be awesome mate! Good luck!! No because i'll change it back if that happens mate . I saw a graph for a 230 bhp Vauxhall XE hot rod and it's still got some fat power and not peaky . That had a 4 into 1 and a dead straight exhaust with 1 box
Toby Posted March 18, 2008 Report Posted March 18, 2008 . That had a 4 into 1 and a dead straight exhaust with 1 box Usually as far back as possible
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 . That had a 4 into 1 and a dead straight exhaust with 1 box Usually as far back as possible Like at the back of the car on the end of the pipe !!!!!!!!
MK2Ed Posted March 18, 2008 Report Posted March 18, 2008 . That had a 4 into 1 and a dead straight exhaust with 1 box Usually as far back as possible Like at the back of the car on the end of the pipe !!!!!!!! Interesting... Good thing is u can play with an engine that has potential with different combinations and a bit savings in the sky rocket ramp up the power and beef up the axle etc ...
Guest MK1gaz Posted March 18, 2008 Report Posted March 18, 2008 We've had 3 dyno sessions so far and found out these things : 1= the high peformance air filter is shite and nicks 15bhp !!!!!!!! 2= moving the exhaust cam clockwise 2mm gains 15 bhp . 3= taking off the exhaust system losses 10 bhp . Now this won't apply to all the other engines out there but on mine if i had left the cams at their recommended settings , fitted the air filter and then took the exhaust off on the drag strip i would have lost 40 bhp and not known about it !!!!!!!!!! . There's no subsitute for testing
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