B20 build - Page 13

Amazonjulian · Apr 8th, 2016, 21:33

Spent the best part of half a day at classic and race at Copthorne today for a tune and dyno. https://classicandrace.co.uk/
Andy Cattani is a top bloke with a great competition track record. Really friendly set up. It doesn't mean that you don't get cold beads of sweat rolling off your forhead as your new engine is run up to 5 and 6 thousand RPM. Final result was 100 BHP at the wheels but it was the torque and its consistency across the Rev range that made me so happy. Hopefully the pictures attached will show up OK. What a drive home!

Amazonjulian · Apr 8th, 2016, 21:36

The pics that didn't load first time

Amazonjulian · Apr 8th, 2016, 21:37

Can only seem to load one pic at a time

Amazonjulian · Apr 8th, 2016, 21:38

Last one

Derek UK · Apr 9th, 2016, 12:41

That's an exceptional torque curve, a credit to the cam selection. KG10 did you say. It'll feel really good at 5000 to 5500! They say that the engine feels best where the 2 curves cross over bot yours is a bit far up the range. How much difference was there between the first start up and the final run. How much extra did the manage to squeeze out of it? Actual power might come up a bit after some more miles on the clock.

volvogv · Apr 9th, 2016, 13:28

Julian, the prospect of running a freshly overhauled engine up to high RPM would give me the shivvers too! Congrats on a successful overhaul.

A few days ago I needed to drive to the state of Iowa so I took the Amazon out, keeping around 55-60 MPH. Some drivers must think that old cars are slow because one was preparing to blow by on an uphill passing zone. I opened it up, still in 4'th gear and accelerated so fast the poor guy couldn't pass me!

Hat · Apr 9th, 2016, 14:47

Quote:

Originally Posted by volvogv

Julian, the prospect of running a freshly overhauled engine up to high RPM would give me the shivvers too! Congrats on a successful overhaul.

A few days ago I needed to drive to the state of Iowa so I took the Amazon out, keeping around 55-60 MPH. Some drivers must think that old cars are slow because one was preparing to blow by on an uphill passing zone. I opened it up, still in 4'th gear and accelerated so fast the poor guy couldn't pass me!

It is rather gratifying when that happens, the presumptuous have an eye opening experience when they have to pull back in behind.

Amazonjulian · Apr 9th, 2016, 20:48

It certainly is gratifying surprising the moderns. On my way home yesterday it was the take off from the roundabouts that really put a smile on my face. You are correct in remembering that it has the kG 10 cam fitted Derek. We did three or four runs. The first couple were dogged by a problem I had had the previous day- namely the rear carb flooding. As it did so the plugs fouled and set up misfires. The problem was the valves in the float chambers sticking- despite being fairly new. Andy recommended a different style valve- a bit pricy but by this time, I just wanted it done. The first proper run gave 85 horses at the wheels so we truly made quite bit of progress. All the while surrounded by various exotic machinery from formula 3 cars to vintage alfas, astons and e types.

tdz840 · Apr 10th, 2016, 18:49

Quote:

Originally Posted by Derek UK

That's an exceptional torque curve, a credit to the cam selection. KG10 did you say. It'll feel really good at 5000 to 5500! They say that the engine feels best where the 2 curves cross over bot yours is a bit far up the range. How much difference was there between the first start up and the final run. How much extra did the manage to squeeze out of it? Actual power might come up a bit after some more miles on the clock.

Derek my understanding is that both toque and HP always cross at 5250rpm. I don't recall the exact reasons but it involves James Watt and his famous equation.
That torque curve is indeed nice and flat from 2000rpm all the way to max rpm. It must pull like a train and undoubtedly will release a few more ponies as the engine frees up.
Julian, you mentioned in an earlier post that you saw 100 bhp at the wheels, yet the graph shows 85hp. Is there some factor the dyno adds in to compensate for environmental or frictional losses?
I might have to take a drive down to this dyno, they sound like they are knowledgable in the older cars.
What did they charge you for the session?
Russ

Amazonjulian · Apr 11th, 2016, 12:12

You are quite right about the chart Russ. Andy took a punt on where we would get to if we carried on going up the rev range as BHP was still climbing. His estimate was 100. Important should I go for a re- run to make sure I'm on the same wheels and tyres.
He spent three hours on my car and the labour charge from memory- don't have the invoice in front of me was £150. I really rate him.

Apr 9th, 2016, 12:41	#125
Derek UK VOC Member Last Online: Yesterday 13:50 Join Date: Jul 2006 Location: Chatham	That's an exceptional torque curve, a credit to the cam selection. KG10 did you say. It'll feel really good at 5000 to 5500! They say that the engine feels best where the 2 curves cross over bot yours is a bit far up the range. How much difference was there between the first start up and the final run. How much extra did the manage to squeeze out of it? Actual power might come up a bit after some more miles on the clock.

Apr 9th, 2016, 13:28	#126
volvogv Master Member Last Online: Aug 29th, 2016 19:28 Join Date: Oct 2013 Location: Seattle	Julian, the prospect of running a freshly overhauled engine up to high RPM would give me the shivvers too! Congrats on a successful overhaul. A few days ago I needed to drive to the state of Iowa so I took the Amazon out, keeping around 55-60 MPH. Some drivers must think that old cars are slow because one was preparing to blow by on an uphill passing zone. I opened it up, still in 4'th gear and accelerated so fast the poor guy couldn't pass me!

Apr 9th, 2016, 20:48	#128
Amazonjulian Master Member Last Online: May 8th, 2019 07:02 Join Date: Feb 2010 Location: Steyning	It certainly is gratifying surprising the moderns. On my way home yesterday it was the take off from the roundabouts that really put a smile on my face. You are correct in remembering that it has the kG 10 cam fitted Derek. We did three or four runs. The first couple were dogged by a problem I had had the previous day- namely the rear carb flooding. As it did so the plugs fouled and set up misfires. The problem was the valves in the float chambers sticking- despite being fairly new. Andy recommended a different style valve- a bit pricy but by this time, I just wanted it done. The first proper run gave 85 horses at the wheels so we truly made quite bit of progress. All the while surrounded by various exotic machinery from formula 3 cars to vintage alfas, astons and e types.

Apr 11th, 2016, 12:12	#130
Amazonjulian Master Member Last Online: May 8th, 2019 07:02 Join Date: Feb 2010 Location: Steyning	You are quite right about the chart Russ. Andy took a punt on where we would get to if we carried on going up the rev range as BHP was still climbing. His estimate was 100. Important should I go for a re- run to make sure I'm on the same wheels and tyres. He spent three hours on my car and the labour charge from memory- don't have the invoice in front of me was £150. I really rate him.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)