GT Posted March 9, 2013 Author Share Posted March 9, 2013 My mill is a budget 2.6 so as to use stock head gasket. Lightened / balanced, running to 7000 Rpm (sees that regular) I modded the head, modded tubular manifold (did'nt like it so I cut it up and recreated it), Revington TR sprint cam. 37 73 / 73 37 290 duration power band 4000 to 7000, DTA engine management. So if the above were remotely true, let's see the torque curve. There is no point talking about stuff without actually having measured it. I've heard about all these 7000rpm engines, but never seen a single item of valid data from a single one. Sorry to be pedantic, but that is an absolute minimum today,- cos NO resold, repacked ford X-flow cam no matter how well marketed from Kent or Revington will ever give anything like the performance you claim. Link to comment Share on other sites More sharing options...
James Posted March 9, 2013 Share Posted March 9, 2013 Are you back on the Island...... I am indeed, landed this morning — currently suffering a day of aching from sleeping upright — never does me any good. Link to comment Share on other sites More sharing options...
Triumph-V8 Posted March 10, 2013 Share Posted March 10, 2013 How nice to be mentioned Yes, who deserves to be mentioned should be mentioned. The startup of my MS2 with your provided configuration, that of James and my MS1 data made a nice mix that saved a lot of work! Link to comment Share on other sites More sharing options...
Triumph-V8 Posted March 10, 2013 Share Posted March 10, 2013 Sorry, mixed all up... The both have been Nick & James...... Link to comment Share on other sites More sharing options...
GT Posted March 10, 2013 Author Share Posted March 10, 2013 I hope this confirms the "seat of the pants" dynomometer. These curves are all from measured data. As you can see, the CR engine has nowhere near the "sports car feel" of the early engine. Also the Hestec system is overestimating the power losses by DOUBLE, so if you take that into account you can see it's taken 6-7yrs to produce a torque curve on EFI which is genuinely better than a good well built original pi engine. Take that how you may, we will see very soon how much of a "torque killer" the phoenix manifold really is in a matter of weeks, when mine is tested against it. If you then look at the power curve obtained from the engine with 2 simple SUs on this early engine (late "S" manifold) and some really nice mods, you can see it again blows the EFI away. Lastly Bengt's engine in Sweden on 3 Weber carburettors makes even better power than any of the EFI systems, but it was a lot more expensive engine. Excuse the slightly confusing plotting of power and torque on the same graph but I hope it makes a valid point. Link to comment Share on other sites More sharing options...
SP Posted March 11, 2013 Share Posted March 11, 2013 Nice to see my engine mentioned in pink on that plot,if i can ditch the Vitesse dizzy and jolt it it will be even better. Steve Link to comment Share on other sites More sharing options...
GT6 Nick Posted March 11, 2013 Share Posted March 11, 2013 All fascinating - that graph will get saved for later study. For instance, the TR5 torque curve's much lumpier than I would have expected. When my GT6 is finished I'll get it tuned on a rolling road and how its torque curve compares. And then maybe upgrade from the TR5 cam... Link to comment Share on other sites More sharing options...
bestquality03 Posted March 11, 2013 Share Posted March 11, 2013 Here are my rolling road results. 2.5 MK2 pi lump. balanced rotating assembly, rods matched end to end, block decked (recess removed) pistons matched for height and weight, standard head with TR5 camshaft. Ph***ix 6-3-1 and EFI Link to comment Share on other sites More sharing options...
Triumph-V8 Posted March 11, 2013 Share Posted March 11, 2013 That looks confident to me! It is a power curve like I got years ago. The top end is much smoother and not cut & drop like a stone Seems like the engine would rev easily higher than 6000 Link to comment Share on other sites More sharing options...
bestquality03 Posted March 11, 2013 Share Posted March 11, 2013 i'm quite happy with it. could always do with a little more power! Link to comment Share on other sites More sharing options...
GT Posted March 11, 2013 Author Share Posted March 11, 2013 Nice to see my engine mentioned in pink on that plot. I built up quite a lot of results from different people, sent from all over the world. Martin seemed to think this was a good result, and I was pleased to see the various mods worked out as planned. There are one or 2 people using that late modified inlet manifold inc Gair's 2L car. The fact is, when properly sorted, it works. It gives a better result than most Pi/EFI systems, a really linear torque curve, no worries about altitude, WLS or anything complicated. It's what's called a "win-win". Keep it simple, do the right mod, use cheap OEM bits, and it delivers the result. Link to comment Share on other sites More sharing options...
spitfire6 Posted March 12, 2013 Share Posted March 12, 2013 (edited) Here are my rolling road results. 2.5 MK2 pi lump. balanced rotating assembly, rods matched end to end, block decked (recess removed) pistons matched for height and weight, standard head with TR5 camshaft. Ph***ix 6-3-1 and EFI Hi, Was going to mention the crossover was not @ 5252 RPM and then saw it was! Wonder why they used two different scales? Nice and flat. Cheers, Iain. Edited March 12, 2013 by spitfire6 Link to comment Share on other sites More sharing options...
RichardB Posted April 30, 2013 Share Posted April 30, 2013 Interesting discussion! That very shiny looking manifold on page 1 just happens to be fitted to my Spitfire - like my polishing efforts? Bob Tooke used one of those Dolomite manifolds on his EFI Midget and reported great torque. Don't know if he opened it out or not. If you have a look at Bob's website (http://croydon.amphibia.co.uk:76/Inject.htm) he replaced it due to a lack of horsepower, probably caused by a lack of airflow. He ended up replacing it with something a lot like the one me and Tim came up with. Have you any idea if it works? Any flow figures? Why don't you send me one and I'll check it on a flowed head to see what it gives. I think you may be suprised to see, straight linear pipe doesn't work well at all, and as Nick pointed out the twin SU one is pretty bad. + As Nick says, I reckon a modified original one may be better, as they put some odd shaped kinks in it & it has much better damping than the twin SU system. I will know by tomorrow eve, and I'll publish the results. Works fucking great! lol. The amount of torque the 1500 engine now has is absolutely rediculous compared to what it had on twin HS4s. Even with EDIS wasted spark ignition and the Bell 4>2>1 manifold & Phoenix large bore exhaust, it still didn't have anything like what it has now - it almost feels like it has too much at times for the standard gear ratios. Just bolt on mods have made it unrecognisable from the original setup in the way it drives - it's just sooo much better. It's so strong at motorway speeds and doesn't batt an eye at doing speeds over 90mph, whereas before it felt like it was a real struggle. It's still noticeable that it goes off cam over 4000rpm but that's to be expected with the stock 18-58 camshaft. The engine is still untouched, so the real test will be when the CP grind cam replaces it and I can have some head work done to match. Even with an unmodified engine, it feels faster than a well set up standard TR6, which I think is quite an endorsement for the manifold and EFI system I put together. By the way, it's running sequential injection (like the Lucas PI had), which contributes a lot to driveability and torque at lower speeds. If you believe what you read on the internet you'd expect it to be one of those slight improvements that most people don't notice - not in my experience, it was a big step up compared to batch fire. Choosing the injectors is important as not all are created equal. I went with Bosch EV6 injectors with a nice 4 hole wide spray pattern to get good atomisation, originally I was going to use EV1 style ones until I realised they output a thin stream. Coincidentally the EV6 spray pattern is a lot closer (though obviously not the same) to the spray pattern you see when you pull out a TR6 injector to bleed it. Nice cone shape. Better atomisation = more power/torque/efficiency. Link to comment Share on other sites More sharing options...
RichardB Posted April 30, 2013 Share Posted April 30, 2013 Sorry but just don't agree with any of that. The TR6 pi manifolds are the perfect length, and perfect design. Kastner has it totally wrong (as usual),- better quote Kinsler not Kastner as a US Fuel injection authority. The most important dimension is the intake to port cross sectional area, not the runner. Increasing it with longer rampipes as I did and moving the injector out into the trumpet increased peak torque at 5000rpm, which was what I was after, and some drop in top end after 7500rpm. Using a slightly larger barrel filter gets around some of the under dimension problems up stream. As for EFI, I've never yet found an EFI car that ever gave anything remotely like as good driveability as Lucas Injection. http://www.youtube.com/watch?v=yCxar0gz3-I What's this engine had done to it? Looks bloody fast! Link to comment Share on other sites More sharing options...
GT Posted April 30, 2013 Author Share Posted April 30, 2013 What's this engine had done to it? Looks bloody fast! There is a little more news on that one. First of all the diameter of the tube was wrong where it exited the 3-1, so it goes a lot better now, and Quieter! Second, It's not all about torque. What is power without control? The owner picked the car up last week and tested it.... This is what he said (and he does own some other fast cars). "This is a seriously quick car! I filled it with Shell V Power and put it through its paces. It is absolutely awesome with huge amounts of torque right across the rev band. The engine is a bit tappetty, nothing that can't be set right. The suspension gives it good stability around turns. But it does tend to tuck down at the rear upon hard acceleration. As mentioned by an observer I had by the roadside" The latest batch of work got finished on the car 2-3 weeks ago, hence the time between the video above and the feedback. We had a program to evaluate the suspension springs, and that's where most of the effort went. (Designing stuff & testing is what it's all about). Being as I don't have one of these cars myself any more that entailed lots of suspension geometry fiddling and playing with rear toe in/out settings, and getting rid of the awful unconfortable red Bastuck springs. The car did 2000 miles in 2 weeks, so there were some interesting things to sort, as well as fuel consumption testing, which fortunately turned in about 28mpg. I tested a set of the new "high performance" front and rear springs, but found the rear would step out really alarmingly, thanks to the Spax dampers running out of travel. In the end we also got feedback from Germany only TODAY, confirming the original Prototype test conclusions, from what was just a off chance idea a year ago, to make some more suspension components which we know work great on the Spitfire. You see it takes a YEAR to get a product from proto to testing & evaluation thru QC to re-correcting to signing off on it. I'm sure they doen't mind me printing the mails....one of which was in German, so get out your G. T. (Google translate). September:- "die Federn sind von der Härte und Progression sehr gut! ...... Insgesamt könnte der Wagen aber tiefer kommen. Daher würde ich die vordere Feder um 5 mm kürzer machen und die hintere nur um 15 mm länger. Vor einigen Wochen hatte ich dir ein Bild geschickt. Man sieht, wie der Wagen gleichmäßig steht, aber er könnte etwas tiefer liegen. Um das Übersteuern zu vermindern habe ich den hinteren Stabi wieder ausgebaut. Mit den roten Bastuck Federn hatte er Sinn gemacht, nur mit deinen Federn geht das nicht. Liegt es etwa am höheren Schwerpunkt, weil die Federn länger sind" End April (different person) "'back today. Did a lot of test kilometers driven on the Rhine ring (260 km). http://www.rheinring.com/fahrtraining/ I am thrilled the springs work wonderfully. It was a great fun with a TR 6 to overtake some Porsches". All I can really say.... About 18 months ago we changed some Spitfire springs out, and the car was instantly faster. This led to some more being done. I had no problem previously following a 450 000km 1500 Spitfire in Paris region with my Jag (which we know do 0-100km/h in 8s). In March I attempted to follow (Sylvain) through some roundabouts (same high mileage 1500 engine maybe only about 65bhp). I was completely unable to follow his car, no matter what. Each sharp bend it just vanished! So the fastest most impressive cars are those which GO ROUND CORNERS! Link to comment Share on other sites More sharing options...
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