| Author | Message | ||
| James Lee (Aventino)
Junior Member Username: Aventino Post Number: 81 Registered: 6-2003 |
Pete, I just printed what I read and I agree that the transaxle has remained up until that was printed. Would be nice if they had said why they went transverse instead of in line. Any thoughts? I would have thought considering how much effort they put into moving the engine back a few centimeters that weight distribution favoured the transaxle over a gearbox bolted to the engine. Mitch, thanks for that, I've heard varying stories about a replacement for the small block and think maybe it's only a matter of time. C6 is too far gone, C7 maybe? | ||
| Mitch Alsup (Mitch_alsup)
Intermediate Member Username: Mitch_alsup Post Number: 1002 Registered: 4-2002 |
"Rumours of the C6 going overhead cam but I'm not sure how far away it is." Never happen, without a dry sump, an OHC V8 will not fit under the bonnet of C5 or C6. And GM will never dry sump a street engine. | ||
| PSk (Psk)
Member Username: Psk Post Number: 910 Registered: 11-2002 |
James, I do not think this means that the gearbox is attached to the back of the engine, rather they have had to turn the gearbox 90 degrees to be inline with the driveshaft instead of transverse ... inline must be how the production 550 is. Thus they are still running the transaxle. That is how I read this anyway ??? Pete | ||
| James Lee (Aventino)
Junior Member Username: Aventino Post Number: 80 Registered: 6-2003 |
Here's what Racecar Eng said: The design of the transmission was complicated by further rule differences - FIA rules permit sequential shifts; ACO/ALMS rules require a H gate shifter. However a bigger issue surfaced on the cars debut at Silverstone's FIA GT round in May 2001, in what Howard-Chappell (Prodrive) diplomatically refers to as a 'difference in interpretation of the rules.' The letter of the rules stated the gearbox had to be in the same location as in the production car, but as Prodrive saw it that didn't preclude the use of a transverse layout in a gearbox thus located. But there had been a rule change since BTCC days when Prodrive were last in Production modified racing that they weren't aware of. So the F550 wasn't permitted to run until Xtrac redesigned an in-line gearbox which took a further 5 weeks. The engine wasn't allowed to enter the cockpit as cocpit dimensions had to remain the same so they machined off the outer corners of the cylinder heads and cam covers thus providing a chamfer that enabled a few more centimeters of rearwards movement without altering the firewall. With the engine so far back and lowered the steering rack can't pass underneath any longer so the rack actually passes behind the cambelts. The article was Nov 2002 so much may have changed. Interesting though. | ||
| Greg (Teflon)
New member Username: Teflon Post Number: 49 Registered: 5-2003 |
I just took a quick glance at the rules and I cannot find anything in there that says the transmission must be moved. Anyone else care to look? http://www.lemans.org/sport/ressources/pdf/2003_REGULATIONS_GTS_GB.pdf Greg A | ||
| James Lee (Aventino)
Junior Member Username: Aventino Post Number: 79 Registered: 6-2003 |
Sorry Mitch, I mean't Me and my Dad are competing with a big block Chev. Not "we" as in Ferrari. As for displacement, the pushrod Vette is starting to lose out in the horsepower stakes as the 550 seems to be getting quicker and quicker in a straight line. Rumours of the C6 going overhead cam but I'm not sure how far away it is. | ||
| Jeff Green (Carguy)
Member Username: Carguy Post Number: 481 Registered: 10-2002 |
Did the vette guys have to move their trans too? I'm not schooled up on the rules, but it seems prodrive is at a disadvantage, less capacity motor, and not an ideal weight distribution. If they can do as well as they are against the vette with an engine 1 or more liters bigger, I'd say that's amazing ! | ||
| rob guess (Beast)
Member Username: Beast Post Number: 262 Registered: 5-2003 |
One other thing to realise here that the rules force ProDrive to move the transmission to the back of the engine block from the rear axle. but they were also allowed to move the engine back to help distribute the weight balance. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 1000 Registered: 4-2002 |
"We're competing with a blown Big Block Chev" A) it is naturally asperated, B) it is not from the Chevy Big Block era (396, 427, 455), C) however, the C5R block starts at 7 litres from the castings. | ||
| James Lee (Aventino)
Junior Member Username: Aventino Post Number: 73 Registered: 6-2003 |
Article in Racecar Engineering says it was bored to just under 6 litres. They could have stroked it but the design, if you are running restrictors, apparently favours capacity through increased piston surface area. We're competing with a blown Big Block Chev and thought we had a rough handle on bore vs rod/stroke ratios. You never stop learning. | ||
| Lawrence Coppari (Lawrence)
Member Username: Lawrence Post Number: 754 Registered: 4-2002 |
Thanks all.... | ||
| Racer Nika (Racernika)
Junior Member Username: Racernika Post Number: 56 Registered: 7-2003 |
The little V12 beauty is currently 5853cc, though there is a 5982cc version, for special occasions. Standard capacity is 5474cc. | ||
| Martin - Cavallino Motors (Miami348ts)
Senior Member Username: Miami348ts Post Number: 5845 Registered: 5-2001 |
I can ask Sen. Rafanelli for you in September  | ||
| Willis Huang (Willis360)
Intermediate Member Username: Willis360 Post Number: 1480 Registered: 8-2001 |
I believe it's 6 liters in both the Prodrive 550 and Rafanelli 550. | ||
| Tillman Strahan (Tillman)
Member Username: Tillman Post Number: 897 Registered: 11-2001 |
Heck, it took less than 2 minutes to find the answer on Prodrive's website. | ||
| Lawrence Coppari (Lawrence)
Member Username: Lawrence Post Number: 753 Registered: 4-2002 |
Since I have gotten no response from the Racing Thread branch of the FChat, I'll ask the same question here. The ALMS Corvette is 8 liters displacement, so I have read. What is the engine size of the 550? Surely it has also been enlarged. Anyone know? |