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Mats
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Post by Mats »

Hey, do I combust when you talk about Beider Meinhof Wagens? I know they build technically superior machines and I don't really have a "baby-brother complex", I even like the cars. :P
BTW, I frequent a very nice Swedish site that is all about racing and you'd be suprised how many BM guys that has suffered spun bearings (E46) or cracked blocks and burnt valves (E30). :P

Micke: VR6? Where did that one come from? :D
You're probably right about rods though, why look the small problem when you have the big guy (revs) to deal with.


By the way, when did we talk about runner diameter? I haven't yet found out how to approximate that. Mean flow at a certain speed?
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
Jim K
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Post by Jim K »

Is there such a thing as an 'ultimate engine' ? Where do you draw the line? Money or extravaganza? Can it have the Coates rotary valve conversion? Why not? Why use TB's at all? Whats wrong with the Variable Throat Venturi (you know, the one with the elastic tube with the four movable outside rollers)? Then we have simple stuff like Ti rods, hollow crankpins, cermet coated ports/chambers and why not, 300*C operation, to drastically decrease thermal loss! Its all possible in a research money-no-problem project. :roll:
Naahhh! I'll stick to Jim's customers, I'm one of them! :lol:
Ok Mats, you've humbled yourself admitting BlowMeWang make better machines, all's forgotten! I'll bet you're the swedish M3 disaster site administrator:lol:
Runner diameter? Boy, I can see Z is all ears taking notes! Ok, stock sucks at 34,5mm, 38mm is good enough!(For WHAT :?: )
Jim K.
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Mats
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Post by Mats »

Good enough for birds nesting? ;)

I'm only a moderator for the small part where there is Alfa Romeo racing discussions. Very good non-brand specific track forum, I mean only track related talk. There is even a Nürburgring section. :)

Anyway, I think the limit of how wild you make your engine is either emission laws for a street engine and for a race engine you build an engine but it will not be the end of the world if it transforms itself to one large chunk of weird alloy or thousands of bits (knock on wood), i.e. wallet sized. ;)

So anýway, is it possible to adapt those ITB that Dawie makes for the 24v?
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
kevin
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Post by kevin »

Hi Jim, I have seen both Barry and Dawie use the carbs on the South African GTV 3.0l as ITB. This was about fifteen years ago. They tossed the top half of the carb away and milled some trumpets(7degrees and bout 120mm long) onto the carb base and put injectors into the sides of the trumpets near the base. This was a good solution for guys who were tired of carbs and did not want to chainge heads.
At Dawies workshop on Saturday I noticed a GTV3.0l 12v been prepared for our famous all tar road rally coming up. and the most astonishing thing is that carbs are being used. Dawie did mention he has finally found the 'best' cam combination for the 12v 3.0l which he gave me the specs. You would have to contact him for these but I believe it would be for fast road car not high track screamer (7000rpm). Also some more ITB developement for 24v taking place there by mounting them on end of gta runners reversed to the sides with two pleniums. Nothing new as he has been doing smililar set ups for years.
Finally met Jon(jungle justice) , what a nice chap, he speaks mainly Afrikaans so when he emails in English I think some people battle with his direct translation and find him abrupt which is definatley not the case.
I think your basis of designing the engine around 6500rpm is excellent, as the high end screamers are way to uncomfortable for every day road use.
By the way i also found a Aluminium flywheel at Dawies for the 12v, paper thin with the ring gear pressed on and did not weigh much more than 1.5kg's.
I will put some pics up next week. Got problems downloadig
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Post by junglejustice »

Kevin, what nice comments, thanks ol' boy!!!

It was nice to meet you and you8r dad too - finally puts some faces to the names...

Cheers, JvR AKA JJ...
...to Alfa, or not to Alfa? That is the question...
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Post by Jim K »

Hello Kevin, nice to hear from you! I have a set of FRPA40 Dellortos from the Alfa6 and thought of using the throttle part, but little adaptor manifolds would have to be made, as the 3liter heads are different on the intake side. This would be more trouble for me, than finding ITB's.
As far as high power cams for the 12v go, I could use my own JK303 12mm profile which works great on the 2liter Nord. After all, they are both 500cc cylinders with same intake valve sizes. We are not much concerned with emissions, but on the other hand, I think these 303* cams should be about the max to be used with the 3liter. For people with emission concerns, things are more difficult obviously. The C&B S2 11mm cams for example, may give some good 'fast road' performance, but as far as HC go, I could not reduce them below...1500ppm, a huge number. Studying the cam profiles in detail, revealed that the ovarlap area was unduly large. It is possible to design a performance cam with proper characteristics for the job but then again, the 12v exhaust rocker mechanism would not tolerate high acceleration ramps without pronounced lobe wear, we all want durability don't we? While the Nord and the 24v engines can serve dual duty (street/track), the 12v owner must be prepared for exhaust lobe wear, unless they opt for lighter 8mm stem SS exhaust valves, going from 81gr of weight each,down to 69gr! (The same change for the intakes, will take you from 108gr to 80gr!!). Now, if someone really wants to go lighter, they can remove metal from inside the exhaust followers-a lot of it! Then, you're talking about high rpm reliability for the 12v and no cam-lobe wear! :)
Right now I'm messing with the 12v head flow, discovering some interesting things...All in all, I'm glad the 24v is around!
1,5kg flywheel? Are there any balancing/torsional imbalance problems with the rear (clutch) flywheel? Very interesting!
Keep up the good work, I hear about it once in a while!!
Jim K.
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