Hi. I haven't actually done anything apart from research so far. I've had a few things to sort at home first. I actually put the car up for sale a little while back. But I have had no interest, so i think i'll keep it, unless the right offer comes in. I was looking at some photos and thought this showed my existing manifold quite well. I can see what mr hillclimber means now by poor flow. Richie K
I've only just read this. The reason for the power drop off is exactly what you've said. You're running KR cams. Duration and lift on these won't allow anything else.
I saw your car go and Blyton and it was going pretty hard in fact. Re reading this again I would say improvements should follow some sort of order, else your expectations can be come aligned to changes that may be expensive and contribute little to the overall package. Your enquiry, centres around 'running out of puff at 6500rpm'. You have also told us that you run the KR exhaust camshaft at least in a ported ABF cylinder head? First thing would be to get a dyno test at a established facility to align the engine WOT performance with our thoughts on what we have seen on this forum or what has been experienced from driving our own cars. Front that plot, we can ascertain what sort of torque is available at 6500rpm vs what is the peak torque and start to give direction from there. No doubt the suggestions from hotgolf and mr hillclimber in ordered stages will be helpful in extracting more drive feel from the powertrain, at different speed load conditions. But get a baseline run first would be my suggestion.
My plans are a bit wayward at the moment. I noticed an exhaust blow last time I started the car, and as the exhaust is a poor compression bent type, I should really find a decent exhaust first. I'm also a bit up in the air work wise. Hopefully that'll get sorted soon and I can crack on with the car. I'll get on the lookout for a decent local RR once I've sorted the exhaust. Cheers Richie K
Just waking up an old thread. I now own this car and am looking for some history about it if anybody has any? I've seen this, and in the long run will be looking to give it some more power- so I guess down the line I will want to get some slighter more aggressive cams, although I haven't actually driven it yet to know where I would want the torque/power band to be. For now it's running the above setup, with a new exhaust, and has been sent to an old school carb specialist who has RR'd it at approx 180hp.
I did an ABF recently with a similar spec but Piper 285 cams...274/276 duration. Perfectly drivable on the road. Mapped ignition is worth considering too. You could then see the sunny side of 190hp, with strong pull from low down through to an easy 7k.
Oh that sounds ideal. 190hp is really where I want to be for my power/weight ratio in my class. What would I have to do/get regarding mappable ignition? The car is a racecar only, so not worried about road drivability- that said some nice useable torque for getting out of the twisty bits- I know the final peak power figure is not ultimate concern.
That's easy enough, a decent pair of cams would see power jump from 180 to 190+ easily. Mapped ignition works great. The std ABF sensor in the block could work fine, but you may need a VR6 sensor, depending on the management system you go for.
