Group: I am interested in the times associated with combustion and the best crank angle when peak pressure occurs. Since NASCAR engines turn 9000+ rpm and make...
Rich, Every engine is different ? Put it on the dyno and see where it makes the best power. Then put it on the track and confirm the results. Best power and...
RohanB
newboltz333@...
Nov 3, 2006 12:26 am
12692
... Nascars do things that aren't in the ( physics ) rule book. They are restricted to pushrod engines ( & carbs ? ), and the power they get out of them is...
Ian
iwd@...
Nov 3, 2006 4:40 am
12693
just to throw some figures in the pot, and i will try to get some from the remains of the Nascar Roush people too while i am here. Zetec Mondeo 2.0 1996 my...
http://www.ronhamp.com/portal/default.asp?id=5&mnu=5&ACT=5& content=10 I knew that Ron Hamp had done some heads for the Zanzanis, but this is the first time...
... The induction system is getting the mixture into the cylinder. After that is the area I am interested. I do not think that 50 degrees advance is likely...
It appears that the Zetec is a later design. The TT600 is totally unfamiliar to me. However doing the numbers says that the actual burn time has to be short,...
... No way. The motors are around 360 CID, so divide that by 8 (cylinders) and you get 45 CID per cylinder. NASCAR often runs restrictor plates (equivalent of...
What an outstanding response! You are right, of course, on the cylinder size. I did quote a similar size cylinder of 39 cubic inches as my focus. That cylinder...
Hello; I am building a supercharged motor using different parts (or should I say mismatched?) and I have to modify a set of pistons by machining the crowns ...
I've used .150" as the minimum when machining the crowns of Norton pistons. Not sure where it came from, maybe Smokey Yunick's writings, maybe not. It's worked...
... About what I would expect. ... Seriously ?? Why would a modern 125cc cylinder need that much advance ? Cheers IAN See www.drysdalev8.com for : -...
Ian
iwd@...
Nov 5, 2006 10:18 am
12703
... What engines do they run ? I thought they were restricted to 350 cu.in ? If the Chev LS1, then 3.620" stroke @ 9 krpm is still "only" 27.6 m/s MPS. F1...
Ian
iwd@...
Nov 5, 2006 10:43 am
12704
... Well jrc, you are certainly an interesting character................. Cheers IAN See www.drysdalev8.com for : - Drysdale 750-V8 Sports & 1000-V8...
Ian
iwd@...
Nov 5, 2006 10:51 am
12705
... I have watched a Yamaha R1 motor on a dyno running at 80 deg advance ( on pump fuel ). To save his reputation, I won't say the guy's name, but suffice to...
Ian
iwd@...
Nov 5, 2006 10:58 am
12706
... Depends on the boost you are running, I wouldn't go thinner than standard. I'd do a couple of spare pistons too, you'll probably need them. ... Stay with...
Ian
iwd@...
Nov 5, 2006 11:08 am
12707
Surely if the advance is too great, you lose power and overheat the engine because the combustion pressure builds too early and resists the piston on the...
I was only using the NASCAR engine as an example of a relatively long-life engine compared to some others. The piston speed is around 5400 ft/min, or more than...
but if the burn rate due to compression build and chamber shape is slow then you would not build cylinder pressure until after TDC anyway. Knock/pinking or det...
it was a very slow burn, i do not know whether it was a bad combustion chamber though or bad design over all. At the top end of the rev range it would have...
... long thought to be the limit for long life. ... A long-stroke Manx Norton in the 1930s (100mm) was exceeding 4000 ft/min by a margin @ 8000 rpm - and 4000...
RohanB
newboltz333@...
Nov 5, 2006 5:57 pm
12712
... I have watched a Yamaha R1 motor on a dyno running at 80 deg advance ( on pump fuel ). <snip> There was no measurable power advantage over 40 deg, but the ...
RohanB
newboltz333@...
Nov 5, 2006 6:41 pm
12713
40 degrees advance compared to optimum for FULL throttle best power/torque? The spark plug folks predict overheated plugs with as little 3 degrees "too much"...
Hi Joe ! We use Wiseco forged pistons in CB350 67.5 MM OD and dome thickness's on them are usually .130 inch at cut out for intake valve.Todd Henning talked...
... No, motor was at operating temp.. ... Yep - a MoTec controller, you don't even switch the motor off ( or even take the dyno load of ), just keep tapping...
Ian
iwd@...
Nov 5, 2006 10:47 pm
12717
How critical is small end bushing wall thickness? Might I safely rebush a rod designed for an 18mm pin down to 15mm, presuming that the new pin is equally...
... That would be true at 3,000 rpm, but he was running 80 deg advance at 14,000 rpm and on pump fuel, which is going to be slower burning than race fuels I'd...
Ian
iwd@...
Nov 5, 2006 11:08 pm
12719
... 0.75 - 1.00mm ( 30-40 thou ) wall thickness is normal, you are only going to 1.50 ( 60 thou ) wall. So I'd say you are pretty safe as long as you are using...
