Trying to trace david of pumaracing
Discussion
Rally Ax said:
Lol,,, that's one of features I was on about - but there was another one done before that one which was done with DV. It was just a feature on changing the cam and comparing the std one with the cvh22.
You had at least one of my RS1600i cams (the Puma001) did you not? Any recollections as to how that performed?You can remember a magazine article from 23 years ago but not an actual cam you tried in your car? Ah well, old age comes to us all. June 1996 you had your first cam and lifter set. £100 all in. God I was too cheap. Then another cam in Feb 1998. 60 quid. You must have liked the first one a bit then.
Pumaracing said:
You can remember a magazine article from 23 years ago but not an actual cam you tried in your car? Ah well, old age comes to us all. June 1996 you had your first cam and lifter set. £100 all in. God I was too cheap. Then another cam in Feb 1998. 60 quid. You must have liked the first one a bit then.
oh god. If Puma starts talking about "the war" someone shoot him....... ;-)
Not a clue! With they way they must have been logging power readings (pen and paper) it wouldn't have been difficult to take readings. Maybe trying to show the hairy monster cams were worth having by letting the engine rev out? As I said above, a lot of hard work for not much result.Correct CR is vital to get cams to 'work' properly. For years we have used a version of the Piper 270 for mild road and a 285 for fast road for our MGBs. With experimenting with our inertia dyno, the 285 is only worth fitting if the CR is raised to 10.25-10.5:1 as the power band and bhp improvement is poor at lower, say 9.75:1 CR where the 270 flies, so for most applications the 270 is by far the best option! Track day/rally use with the correct CR the 285 leaves the 270 for dead. I am sure the same will obtain for CVH cam profile Vs CR. Hairy cam lower than optimum CR and the cam tends to be revvy but very soft as shown in the last two CVH cam tests.
Peter
Peter
Trying to get hold of David Baker - Puma Racing Engines - Anyone help??
David, I've been reading through your notes on optimum exhaust manifold size and need some help if you could please on manifold and exhaust sizes for a 2.4 Duratec engine.
The engine is currently running on 1 3/4" primaries; 2" secondaries into 2 1/2" outlet and producing 295bhp and 212 lbsft of torque (manifold was previously used on a 2.0l producing 260bhp and 175lbsft torque). Based on your notes I would think that I should be looking for 2" primaries; 2 1/4" secondaries into 2 1/2" system or 2 3/4" system.
My question is two fold... Do I need a manifold outlet/ system larger than the current 2 1/2" diameter? And in moving to larger diameter manifold am I likely to see much change in power, but more specifically torque from the engine.
David, I've been reading through your notes on optimum exhaust manifold size and need some help if you could please on manifold and exhaust sizes for a 2.4 Duratec engine.
The engine is currently running on 1 3/4" primaries; 2" secondaries into 2 1/2" outlet and producing 295bhp and 212 lbsft of torque (manifold was previously used on a 2.0l producing 260bhp and 175lbsft torque). Based on your notes I would think that I should be looking for 2" primaries; 2 1/4" secondaries into 2 1/2" system or 2 3/4" system.
My question is two fold... Do I need a manifold outlet/ system larger than the current 2 1/2" diameter? And in moving to larger diameter manifold am I likely to see much change in power, but more specifically torque from the engine.
Edited by 27Dave on Tuesday 10th July 10:40
https://web.archive.org/web/20110918115047/http://...
https://web.archive.org/web/20110903091024/http://...
The system you have would appear from my technical article to be perfectly specified for the 260 bhp you used to have on the old engine. The charts would suggest 1 7/8" primaries, 2 1/8" secondaries and 2 3/4" system for your current engine. I doubt if it's being massively restrictive though. Could be a lot of expense to pick up a few more bhp.
Is there any reason you have to suspect your engine is not producing as much as a you were expecting or promised from it?
https://web.archive.org/web/20110903091024/http://...
The system you have would appear from my technical article to be perfectly specified for the 260 bhp you used to have on the old engine. The charts would suggest 1 7/8" primaries, 2 1/8" secondaries and 2 3/4" system for your current engine. I doubt if it's being massively restrictive though. Could be a lot of expense to pick up a few more bhp.
Is there any reason you have to suspect your engine is not producing as much as a you were expecting or promised from it?
Pumaracing said:
However the big trick they missed was just to drop the 1600i solid lifter cam in on the stock hydraulic lifters which is what I did on many engines. The 1600i has more lift than the Piper 270 or 285 or the Kent CVH22 and the same duration as the hottest of those. It therefore beat all of them for power so I have no idea why it supposedly fared so badly in this test.
Hmm Hi again 
just wondering if there are any sources for the highlighted cam...Kccv23highliftcam said:
Hmm Hi again just wondering if there are any sources for the highlighted cam...
I imagine Kent and Piper have the profile available. They'll have copied it from a Ford cam at some point. Mine were done for me by a chap near Uxbridge with his own cam grinder who used to do regrinds for the trade for engine rebuilds. I used to save up all the good s/h OE Ford cams that came out of engines I rebuilt for the XR2 Challenge and he'd put whatever profile I wanted on them from his stock of master profiles. The RS 1600i gave a solid 7 bhp on a stock engine with only a tiny loss of tractability if you ran it on hydraulic lifters which of course made it a hassle free swap. Using the solid lifters and having to shim them up is obviously a major task. People don't seem to realise you can run a solid lifter cam profile on hydraulic lifters without any issues whereas the reverse is impossible. just wondering if there are any sources for the highlighted cam...My next stage cam for competition engines was actually a profile from a Crane Cams Chevy V8 cam with nearly 500 thou lift. They wore out pretty fast though because CVH cams aren't made from the best material.
It was a nice little earner in its day. My guy would reprofile a cam for me for 20 or 30 quid and I could sell them for £100 which was still cheap compared to a Piper or Kent cam.
Yeah changed days indeed on the "tuning circuit".
Makes you laugh though, getting a tune done today usually means altering the engine Beyond Economic Repair parameters to the left!!
Look at the ongoing Ford Ecoboost fiasco, they can't even get them to last in standard form!!
Interestingly enough I have a 81SM6090 BRA and a 88SM6090 head, pity there's no one left to put some bigger valves in them and do a proper job!!!
Edited for correction.
Makes you laugh though, getting a tune done today usually means altering the engine Beyond Economic Repair parameters to the left!!
Look at the ongoing Ford Ecoboost fiasco, they can't even get them to last in standard form!!
Interestingly enough I have a 81SM6090 BRA and a 88SM6090 head, pity there's no one left to put some bigger valves in them and do a proper job!!!
Edited for correction.
Edited by Kccv23highliftcam on Thursday 19th July 21:17
Kccv23highliftcam said:
Yeah changed days indeed on the "tuning circuit".
Makes you laugh though, getting a tune done today usually means altering the engine Beyond Economic Repair parameters to the left!!
Look at the ongoing Ford Ecoboost fiasco, they can't even get them to last in standard form!!
Interestingly enough I have a couple of 81SM6090 BRA heads, pity there's no one left to put some bigger valves in them and do a proper job!!!
There are always people about who can, it's just a case of finding them and whether they are willing.Makes you laugh though, getting a tune done today usually means altering the engine Beyond Economic Repair parameters to the left!!
Look at the ongoing Ford Ecoboost fiasco, they can't even get them to last in standard form!!
Interestingly enough I have a couple of 81SM6090 BRA heads, pity there's no one left to put some bigger valves in them and do a proper job!!!
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