martinwhitcher Posted March 1, 2007 Share Posted March 1, 2007 Well the day has arrived when i get Dave Walker to work his magic on my new DVA super K . To cut a long story short, DVA has built me a high spec K basic spec as follows: 1900cc scholar Heavy Metal Inserted (HMI) crank by Steve Smith @Vibration Free Arrow steel rods (cheers Mav) DVA "ultra" full port with High lift port entry 1444 cams Large valves 45mm Jenveys Bernard Scouse large airbox with 90mm trumpets Anyway after covering over 1000 miles in recent weeks to run-in with a bodge map, today was d-day well after a lot of tweeking to the map for part throttle which was way out, we moved on to a full throttle run, this returned about 220bhp and 165lb which was ok. After some tweeking we seemed to top out at 226bhp and 170lb/ft, torque was respectable however we knew that this spec should be a 240bhp+ spec and where scratching our head to fathom out why we were short After a call to Dave Andrews we decided to check the cam timing. This turned out to be spot on next...... we decided to try a run without the airbox..... BINGO 😬 Instant 250bhp and a new emerald record of 181lb/ft torque for a N/A K-Series all this at less than 8150rpm now the issues seems to be how to release more protental from the airbox combination, please note both Dave's and Bernard have not come across another case of the airbox losses being this much, we have some plans to improve this, and Dave Andrews seems to believe it is crying out for more cam (piper 2180 inlet). Well watch this space.............. Well i must say i am most chuffed 😬 big thanks to Dave Andrews (DVA) Steve Smith Dave Walker All top blokes to deal with and true professionals. Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 207 Edited by - martin whitcher on 1 Mar 2007 21:33:33 Link to comment Share on other sites More sharing options...
edmandsd Posted March 1, 2007 Share Posted March 1, 2007 Nice one Martin Home of BDR700 Link to comment Share on other sites More sharing options...
mav Posted March 1, 2007 Share Posted March 1, 2007 Link to comment Share on other sites More sharing options...
Casbar Posted March 1, 2007 Share Posted March 1, 2007 You need to change your signature Can't wait for a ride at Croix next week 😬 Link to comment Share on other sites More sharing options...
cskip Posted March 1, 2007 Share Posted March 1, 2007 Martin - Rob - You must be mad 😬 Skip. West Hants Luddite See CSKIP here Link to comment Share on other sites More sharing options...
Jason Plato Posted March 2, 2007 Share Posted March 2, 2007 Great result good work fellas is (was) the airbox using the 78mm inlet or the 102 mm inlet ? here is C7 TOP Taffia Area Rep Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 2, 2007 Author Share Posted March 2, 2007 Cheers all, Dave it was the 78mm entry, we think that the area from the trumpets to airbox is not quite enough so i will be looking to be getting the hacksaw and glassfibre to the box to gain precious extra mm where we can, also widening the entry to 100ish mm then experimenting with 50mm and 90mm trumpets when Bernard get them manufactured in 45mm dia, as they seem to flow better than the jenvey trumpets. ps. do you know whether i can retro-fit a std foam filter to the bernard scouse back plate, if so which model number?? Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 250 Link to comment Share on other sites More sharing options...
Jason Plato Posted March 2, 2007 Share Posted March 2, 2007 I think you will need to remove Bernards back plate and go with a ITG JC50 backplate or pipercross . I modified my airbox to run with a 102mm KN filter ( pics in the link below) back in my 1900 K series days . You are welcome to try my modded 102mm inlet airbox on your engine before you chop your box up. The airboxes have given mixed results - I actually gained midrange with the 102mm inlet box fitted , but rob walker lost power with the box fitted (and 102mm inlet). I think the pulse of the inlet, and reflection off the walls of the box play a different tune on each instalation depending on cam spec etc . Dave here is C7 TOP Taffia Area Rep Edited by - Dave Jackson on 2 Mar 2007 08:11:50 Link to comment Share on other sites More sharing options...
Rob Walker Posted March 2, 2007 Share Posted March 2, 2007 Great result Martin. Was the airbox Bernards latest design with increased volume or the mk1? My 1.8K lost 17bhp at peak power and 13lbft torque at 6500rpm, the losses were right across the rev range. However I found the car much more pleasant to drive without the induction roar. Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 2, 2007 Author Share Posted March 2, 2007 Dave, many thanks for the offer bernards going to send me one to "play with" 😬. will the foam filters fit under a std non air filter cut bonnet and can you remember the model numbers?? Rob, it is bernards latest design with 78mm entry. lots of work to still do 😳 Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 250 Link to comment Share on other sites More sharing options...
old captain slow Posted March 2, 2007 Share Posted March 2, 2007 Looking forward to seeing this go. C7 CDW Link to comment Share on other sites More sharing options...
Jason Plato Posted March 2, 2007 Share Posted March 2, 2007 The ITG JC50 back plate is the size you require - which is the size to fit the K series (and duratec) trumpets / port spacing), the filter is then an ITGJC 50 but the depth of the filter is dependant upon your length of trumpets, the throttle bodies / rollers you are using and the injectors and position of fuel rail. You need to have a minimum of 25/30 mm clearance from the tip of the trumpet to the inside of the filter, so if you are using 90mm trumpets you would use a minimum of 120mm deep JC50 air filter if you mount it on the throttle bodies / head interface or you could use a ITG JC 50, 25/30mm deep if you mounted the filter on the very tips of he trumpets (my personal choice method) The clearance between the trumpets and bonnet is closest on number 1 cylinder - simply remove the air box and nose cone and put the bonnet on and you will be able to measure your clearance and space available for the filter. You *should* be able to run without a bonnet cutout. But you will then be drawing warm air. Every 10C reduction in induction air temp is about 3% power, so you could easily "loose" a potential 15bhp if you draw air from under the bonnet at 30C (ie 20C greater then ambient) all good fun here is C7 TOP Taffia Area Rep Link to comment Share on other sites More sharing options...
old captain slow Posted March 2, 2007 Share Posted March 2, 2007 If you intend to run without the air box next week you may take the prize for noisiest car from Mike C (105.9 dB). But there again if you go in the gravel you may need a new engine. C7 CDW Link to comment Share on other sites More sharing options...
Jason Plato Posted March 2, 2007 Share Posted March 2, 2007 {Duratec PR head on } the k series engine will need a refresh after a trackday anyway, so a bit of gravel wont harm enjoy the power oversteer at 90mph here is C7 TOP Taffia Area Rep Link to comment Share on other sites More sharing options...
DSL Posted March 2, 2007 Share Posted March 2, 2007 Jackson you turn coat 😬 Good result Martin Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 2, 2007 Author Share Posted March 2, 2007 Well i should have the ITGf ilter and backplate tomorrow, however the backplate is a blank, as they said they couldn't match one to my pattern?? David, just bring the sun, and i'll bring the noise 😬 (i'm sure it won't be as loud as mike's though ) looking forward to next friday 😬 Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 250 Link to comment Share on other sites More sharing options...
Casbar Posted March 2, 2007 Share Posted March 2, 2007 Martin, I'll bring the van to carry the bits back Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 2, 2007 Author Share Posted March 2, 2007 😳 Link to comment Share on other sites More sharing options...
bobt Posted March 2, 2007 Share Posted March 2, 2007 Hi Martin - great result!! I actually have a question regarding your previous engine Were you using the regular sized BS airbox with the 70 something mm diameter inlet and 50mm trumpets? Cheers Rob Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 3, 2007 Author Share Posted March 3, 2007 Hi Rob, yes that used bernard's mk 1 box with the small inlet and 50mm trumpets. That made 207bhp and 147lb WITH the airbox on, we never even tried a run without it, I always thougth that was a very strong engine. Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 250 Edited by - Martin Whitcher on 3 Mar 2007 06:38:01 Link to comment Share on other sites More sharing options...
swifta Posted March 3, 2007 Share Posted March 3, 2007 Hi Martin, You have got me thinking now as to weather a change of airbox and trumpets might be in order.As you know I bought your old engine,which I might say pulls like a train but if theirs more to be found buy changing airbox a session on the rollers looks favorite. Pleased to hear you have achieved the output that you have. Cheers Swifta. Link to comment Share on other sites More sharing options...
oilyhands Posted March 3, 2007 Share Posted March 3, 2007 Hi George, So it's behaving itself then :-)) Oily Link to comment Share on other sites More sharing options...
swifta Posted March 3, 2007 Share Posted March 3, 2007 Hi Dave, Yes its going realy well,i,m looking forward to doing some competition and learning how to use it properly.Do you think I,d benifit from a better/modified airbox? Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted March 3, 2007 Leadership Team Share Posted March 3, 2007 When Fred had his dayglo R400 (Fred of Wiley glasses fame!) he used the Caterham CF airbox, but decided to fit a fourth inlet rather than keeping to the standard 3. IIRC he had done some flow tests (possibly on paper) and believed that anything over 200bhp or so would be restricted by the airbox design if it retained only 3 inlets - I think the Reverie/Caterham CF airbox is a 150mm throat linked to 3 x 55mm inlets. Stu. Link to comment Share on other sites More sharing options...
martinwhitcher Posted March 3, 2007 Author Share Posted March 3, 2007 After looking at the situation today, it appears there is plenty of space between the end of the trumpet (90mm trumpets) and edge of airbox = 80mm extra, the min suggested is 25-30mm. So i have made the assumption that the inlet for th air filter which is 78mm is far too small, i am thinking of making that 100mm and also adding another inlet the pedal box side and feeding air around where the heater used to be, maybe even using the sealing of the old heater unit so that colder air is from outside......... watch this space..... ps. I tried to fit the ITG filter and back plate, but it was not going to fit due to the rover fuel rail etc.... ☹️ Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 250 Link to comment Share on other sites More sharing options...
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