MacP Posted January 15, 2014 Share Posted January 15, 2014 My engine is now up and running and has been dyno-ed at Emerald having been installed by the 7 Workshop. The engine spec is a VVC with - DVA's K06a kit - 1.9 Scholar block - Powerspeed 4-2-1 - Emerald K6 I wanted reliability, torque and flexibility rather than outright grunt. Power is 172.4 bhp at 7010 Torque is 154.6 lbs/ft at 4721 Dyno Plot Oily says the torque looks good but it's tailing off faster than he would expect so at some point I may get him to look at it. But not until I've got it back and at least run it in. Link to comment Share on other sites More sharing options...
Area Representative Golf Juliet Tango Posted January 15, 2014 Area Representative Share Posted January 15, 2014 Great news Ewan. Are you still running on 14" wheels and big profile tyres? Perhaps you can run it over to the Ace Cafe next month? (11 Feb) Link to comment Share on other sites More sharing options...
MacP Posted January 15, 2014 Author Share Posted January 15, 2014 Now on 15 inch anthracites on 55 profile because I couldn't find any suitable tyres in 14 inches (it was A048s or nothing). When car is finished I will give a full update. I might make February but more likely March. Chris has got to put it all back together. Link to comment Share on other sites More sharing options...
Area Representative Golf Juliet Tango Posted January 15, 2014 Area Representative Share Posted January 15, 2014 The 15" multispoke Caterham wheels do work well on the 21. John Bell found this as did I. D21P has used them with CR500 on track. Like you I use them with 55 profile tyres. Link to comment Share on other sites More sharing options...
jackb_ms Posted January 15, 2014 Share Posted January 15, 2014 Cool I was pondering about a 1.9 VVC engine 😬 Thinking about a 1.8 VVC supercharged engine now 😬 Jack Link to comment Share on other sites More sharing options...
revilla Posted January 15, 2014 Share Posted January 15, 2014 Did you retain the VVC system or blank it off and fit solid cams? Link to comment Share on other sites More sharing options...
MacP Posted January 15, 2014 Author Share Posted January 15, 2014 Quoting revilla: Did you retain the VVC system or blank it off and fit solid cams? I've retained the VVC system. I wanted low down and mid range torque and a mild tune. The big bore was rumoured to have a greater than proportionate effect on torque and given it's 8% higher than the best performing K06a (compared to a 5% capacity increase) this seems to be true. The standard engine had a torque peak of 128 or 130 in the later version. You can see from the curve that my engine is above 128 all the way from 2,500 to 7,000. Link to comment Share on other sites More sharing options...
revilla Posted January 15, 2014 Share Posted January 15, 2014 Very nice. I know when people go for more power they tend to remove the VVCs but I must say I love the flexibility and drivability of my VVC engine. Good to know there are sensible tuning routes for those of us who want to stay with VVC. Link to comment Share on other sites More sharing options...
Mankee Posted January 15, 2014 Share Posted January 15, 2014 What a nice fat torque curve, ideal for road use. A 1900 conversion (from whoever) makes so much sense when the cost isn't that much more than just a set of forged 1800 pistons. If it's a fresh build, there will be more to come after it's had a bit of a hammering. Link to comment Share on other sites More sharing options...
Area Representative Golf Juliet Tango Posted January 15, 2014 Area Representative Share Posted January 15, 2014 You need the torque for the 21, which weighs 700-750kg. It's why the 1600 was not suited to it at all (it was very much a cruising car). An 1800 (or 1900) fits the car much better. Link to comment Share on other sites More sharing options...
MacP Posted January 16, 2014 Author Share Posted January 16, 2014 Quoting Mankee: What a nice fat torque curve, ideal for road use. A 1900 conversion (from whoever) makes so much sense when the cost isn't that much more than just a set of forged 1800 pistons. If it's a fresh build, there will be more to come after it's had a bit of a hammering. It is a fresh build (by Oily). Chris at 7 Workshop said engine is still tight so would get a bit more power with time. Link to comment Share on other sites More sharing options...
MacP Posted July 17, 2014 Author Share Posted July 17, 2014 I now have the car back and had engine re-mapped as it was pretty rough at idle. It now drives beautifully. Compared with original dyno run I appear to have lost some torque. Dyno plot Might be influenced by fact it was a very hot day (15 July) and the original run was done on December 19 but maybe original numbers were a bit optimistic. It is still tailing off faster than other VVC engines. Overall it's doing what I wanted, which was provide similar power to a VHPD but with more torque, lower down. Geared so that theoretical max speed arrives around the power peak (implied 145 mph at 7,000 revs) - tested using this calculator Performance calculator. Calculator also suggests that car might get close to Autocar's test figures for the VHPD for acceleration (4.5 seconds to 60 and 11.1 seconds to 100). Link to comment Share on other sites More sharing options...
Guest Posted July 18, 2014 Share Posted July 18, 2014 Hi, The 21 is very susceptible to air intake temperature. Using the mems ecu, roller barrels with vvc mechanism ive seen over 60deg underbonnet temp which retards ignition and vvc mechanism. I have put airboxes and hoses to pick up cold air. Dave Link to comment Share on other sites More sharing options...
MacP Posted July 18, 2014 Author Share Posted July 18, 2014 Quoting 21jigsaw: Hi, The 21 is very susceptible to air intake temperature. Using the mems ecu, roller barrels with vvc mechanism ive seen over 60deg underbonnet temp which retards ignition and vvc mechanism. I have put airboxes and hoses to pick up cold air. Dave I think that my air intake temps were similar to that level. Coolant temp was c. 98°C. Emerald blow air in to the front of the engine but intake is at the side. I'm using a plenum and the original air intake. Where have you located the air intake and what kind of piping are you using? I was wondering if it's worth heatwrapping or coating the exhaust headers to reduce underbonnet temps (which seem very high). Plenum gets very hot. Link to comment Share on other sites More sharing options...
Guest Posted July 18, 2014 Share Posted July 18, 2014 Hi, Compared to the seven the 21 is paneled in for high speed stability hence it is very difficult to get sufficient air in and to get it out again. I would grab the air from the inner wing to start with. ronnie gibson has run with the bonnet unlatched leaving a gap in low pressure area in front of the windscreen which cools the engine compartment. I will send some pictures of jigsaw air intake but even this gets hot on part throttle. Possibly the sensor is measuring heat soak from the engine rather than the air temperature hence I have added another sensor in the air box backplate and will compare in the near future Dave Link to comment Share on other sites More sharing options...
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