Over the last 6 months or so I have been involved with Simon Thornley in specifying and building a 1900K for his sprint car. The brief was to produce an engine with good peak power but not too much mid range torque due to the restricted grip offerred by the tyres allowed in the class in which he competes at Curburough.
Simon is an ex Rover engineer who has held the championship and course record at Curborough for a couple of years.
After much joint deliberation Simon decided to go for more aggressive cams than the current favourites (1444s) in order to bring down the low end torque and bring up the peak power. The head work was discussed and I undertook some experimental port work together with some fairly large valves (specially made for me and now available as a stock REC part) with larger inserts in the VHPD head. The induction is the stock VHPD/Exige PTP type DTH bodies with some modifications to suit the port work. The exhaust is a 4-2-1, the ECU is of course, an Emerald M3DK.
The engine was run up and mapped by Dave Walker in his usual brilliant manner on Emeralds RR yesterday, Dave remarked that it was slightly disappointing since it didnt quite make 264BHP. The result was 263.7BHP at 8850 with 171.7lb/ft at 6920. The power was still climbing at this point but the collective bottle ran out and a 9000RPM run was decided against.
Needless to say Simon was pretty pleased with the results but has embarrassing amount of torque which we may need to curb by backing off the timing a little here and there.
It looks as if we chose too much cam since the engine hadnt yet peaked at 8850… still I dont suppose Simon will mind.
What a cracking engine the K is… and congratulations to Simon on such a brilliant result.
Great result Dave.
As Simon S can not post on here he asked me to say how impressive a result it is, and it shows with the right expertise and effort a k series can make good results.
An engine as stressed as this one wont last forever if it is used in anger. It will be refreshed each season so there will be little opportunity to assess longevity.
The owner is a little sensitive about publishing the power curve and I have to respect his wishes. Suffice to say that the engine has over 160lb/ft at 5000 and ccontinues with 160lb/ft+ until 8500RPM.
"ue and bring up the peak power. The head work was discussed and I undertook some experimental port work together with some fairly large valves (specially made for me and now available as a stock REC part) with larger inserts in the VHPD head.
THESE ACCORDING TO PAUL IVEY ARE THE 34.5MM VALVES HE STOCKS. THESE WERE COMMISSIONED BY JUDD 3 1/2 YEARS AGO FOR THEIR BTCC EFFORT AND HAVE BEEN AVAILABLE THROUGH PAUL EVER SINCE - TO ANYONE. DVA HAD NOTHING TO DO WITH THEM EXCEPT - NICE ONE DVA… "
Once again you are incorrect.
The valves were in fact 33.5mm and were commissioned by me some 6 1/2 years ago for Mark Bishops head (amongst many others) to replace some K8 valves that were fitted by SP performance to his head. They are now available as a stock REC part (as mentioned in my original post). These predate Judd’s request by some considerable time (3 years or so). They are mentioned in my K series page (C 1999) and the DVApower web page (C 2002).
The forgings were specially made and I believe Paul uses the same forgings for the 34.5mm valves…
Don’t post crap Simon, I know you are keen to spit venom, just make sure you get your facts right… I suppose an apology is too much to ask for ))
Shoot, foot, to, in , oneself, the…
Arse, making, oneself, an , of…
I have better things to do than to show the innacuracies in your posts, if you cant post anything that contributes then dont post at all. What was the purpose of the posting?
Dave
P.S. Simon Thornley tells me that he has now taken the engine to 9300 and the power appears to be still climbing.
))