Alfa V6 Engine Building

[JohnB_SPY8808053]

Hey all. I was wondering if anybody wanted to start a discussion about race preperation for the Alfa Romeo V6.

I'll start with transaxles - I noticed that the rally prepared Corse S in the classified section has LSD and dog engagement. I didn't know these things were available. Anybody know the details?

Thanks,

John B.


PS - I've Been working on Stratos Trivia #3. It will be hard but maybe not quite as hard as the last one. ;) I should have it ready sometime next week.

[Stratos]

John,

The transmission and LSD in Andrew Dearing's Corse S was prepared by Avanti in the UK, but all the parts were sourced from Italy apparently. It allegedly was quite expensive.

I contacted Avanti when I wanted an LSD for my car, and they were pretty expensive. So much so, that I ended up getting a batch of LSDs designed and manufactured by Gripper Diffs in the UK at a very reasonable price.

The initial batch is all sold out, but we could get another batch made. I'm very pleased with the one in my car, although I haven't really done enough competitive mileage to give the full picture. After Abingdon, hopefully, I'll be able to give a more accurate comment.

Quaife in the UK also claim to supply an LSD for the Alfa transmission, but, when you speak to them, it doesn't really appear to exist.

As regards the transmission, Andrew is the only person I know of who doesn't just use the standard gearbox.

A cheap upgrade on the gearbox is to use the 24v gearbox, as apparently, the internals are slightly different, and stronger, to the 12v gearbox.

Diff ratios is another area of concern, and deciding what to use wil be dictated by what use you will have for the car.

If you are using it on the road, keeping the standard diff ratio will reduce the revs when cruising. For competition, get the lower ratio (i think the 24v already has this) for better acceleration.

Hope some of this is useful.

[JohnB_SPY8808053]

That sounds like a good idea to me. I have not talked to Quaife myself, but I have heard the same thing about their 164 LSD from others. If you don't mind me asking, about how much does the Gripper Diff. cost?

Since the 24v engines are much cheaper more familiar to the mechanics on your side of the pond, I was planning to have the engine built over there and shipped to me complete. John Rutter has reccomended AHM Motorsports (http://www.maxinternet.co.uk/ahm/) to build the engine - I really like the way their finished 24v engines with the cross-flow intake manifolds and outer valve covers removed look. (They remind me a lot of the fuel injected Dino 12v engine.) More improtantly though, I like the idea that John R. knows and reccomends them.

When the time to get the engine comes (Summer 2005), I will have to depend a lot on their advice, but I do have some idea what I am looking for. My idea is to increase the engines capicity as much as possible but keep it (more or less) reliable by using the best parts I can find and trying to stay within their limits. Below is my most recent estimated parts list - any advice or opinions would be most appreciated.

Ciao,

John B.


John's Dream Engine:

$3500 Alfa 164 LS LongBlock Alfa & 164Q Transaxle
$3000 Electromotive Tech III ECU & Ignition System
$ 100 Magnecor Plug Wires
$____ 2x Bosch High Capacity Fuel Pumps
$1500 6x Jenvey Injectors
$____ AHM Cross-Flow Intake Manifold
$ 600 Colombo & Bariani Rally Cams
$1000 Head preperation
$ 500 Borgo/Mondial 101mm Piston Liners (3.5L)
$1250 Venolia Forged Hypereutectic Pistons (11:1 CR)
$____ Gapless Rings
$1250 Carillo Connecting Rods
$1000 Block, Crank, Rod & Piston Preperation
$1000 Ceramic/Thermal Coatings & Surface Treatments
$ 250 Baffled, Reinforced, Low-Profile Sump
$ 400 3qt. Accusump with Electric Valve
$ 500 Lightened Flywheel
$ 500 Helix/Tilton Semi-Rigid Rally Clutch
$____ _____ LSD
$ 500 Exhaust Manifold Fabrication
$ 250 2x Supretrap 14"x5.5" 'Shorty' Mufflers

[Stratos]

John,

Spec sounds impressive.

The LSD from Gripper Diffs is £750(Sterling)

[JohnB_SPY8808053]

Thanks. I should mention that those prices are just estimates. I have not actually discussed it with an engine builder yet because I won't be ready to make the purchase for another year or two. If anybody can think of anything I've missed or has any better ideas, please let me know.

That seems like a good price for the LSD. I'm guessing it must work pretty well or you wouldn't reccomend it.

John B.


PS - In case anyone is interested, here's a picture of the Alfa 24v engine from AHM (left) and a fuel injected Dino 12v engine (right).

[Stratos]

Originally posted by JohnB_SPY8808053

That seems like a good price for the LSD. I'm guessing it must work pretty well or you wouldn't reccomend it.



I haven't done enough competitive miles yet to give a firm opinion, but it seems OK. Hopefully, I'll be able to give a better indication after Abingdon.

[David May]

The AHM staright-ported manifolds look very purposeful - not so sure that I fancy having those 3 rear trumpets poking out of my rear louvres though!?

Dave M

[Stratos]

David,

That's a vetry good observation. I don't think anyone had considered that aspect.

I would certainly have a major problem fitting them in my Allora.

I would think that anyone considering purchasing them should do some measuring bfore committing to them.

[Stratos]

Just thinking about David's point about clearance.

Do anyone, who knows anything about throttle body mechanisms, think that it would be posible to manufacture a set of throttle bodies out of the standard inlets which go from the standard plenum chamber?

[rutthenut]

David (W).

Were you considering the possibility of fitting throttle nodies onto the shiny intakes, which point towards the rear of the car? I guess it would be possible to get some form of adaptor to do that, and also to maybe switch them around to face the front of the car. Otherwise there would still be issues with clearance with both the body panels and the rear chassis cross-member.

As for the actual manifolds in the photos, AHM have two lengths available. I believe it is the longer ones shown in the photo. These are being used for a 'control engine' being built for use in a German single-seater formula (against BMW six-cylinder engines). The shorter ones allow the setup to be used in an Alfa 75, for instance.

FYI: Graham Scott has an AHM throttle body system on his car now (the ex Tony Soper/Lionel Gooch car). So it can fit under the rear deck without surgery, although I don't know which length of throttle body he is using.

Cheers,

[Stratos]

Originally posted by rutthenut
David (W).

Were you considering the possibility of fitting throttle nodies onto the shiny intakes, which point towards the rear of the car? I guess it would be possible to get some form of adaptor to do that, and also to maybe switch them around to face the front of the car. Otherwise there would still be issues with clearance with both the body panels and the rear chassis cross-member.



John,

Yes, that's what I was meaning.


Originally posted by rutthenut
FYI: Graham Scott has an AHM throttle body system on his car now (the ex Tony Soper/Lionel Gooch car). So it can fit under the rear deck without surgery, although I don't know which length of throttle body he is using.

Cheers,

That's interesting to know. I'm hoping to go down to Castle Combe tomorrow to watch the Auto-Italia race, so I might see if I can get some pictures of Graham's installation.

Thanks for the info.

[JohnB_SPY8808053]

If you get any good pictures, would you post them or email them to me.

Thanks,

John B.

[Stratos]

If I get anything, i'll try and post it on here.

[rutthenut]

Dunno if you made it along to Castle Combe, but I went to watch on Monday.

Graham Scott did not use his Stratos, as he was using a Ferrari that day instead - competing in the Maranello Challenge as well as the Le Mans Auto Italia series.

<winge>
As a side note, this is one of the occasional problems with the Auto Italia championship, as the Ferrari crowd have a couple of meetings in common and hence enter both races at those meetings. That in itself is fine, it makes a better spectacle and all that. Trouble is, they register for the series and their high-spec (and, naturally, high price) cars tend to take away the top spots in the Auto Italia race. In doing so, they also take away the points for those positions, which can be a bit of a bummer if you are in the same class as them. This can affect the overall championship to some degree, as the class winners in the lower ranks can still get maximum points if not up against the Ferraris. The solution to this would probably be for Tony Soper to not award the points unless the cars have committed to at least attempt a full season (difficult one to police, that). Since they would not all have run the correct stickers, then in theory that should disqualify them from the points awards too. The other alternative is to rent or buy a Ferrari too - but that is out of reach of most of the club-level competitors in this series.
</winge>

Still, I shouldn't really complain about this point as it's all sounding like sour grapes. It didn't stop me from winning, and I also got to beat some of the Ferrari's on the track (when wet).

Back to the original point, Graham didn't use his Stratos but did have it there. I don't know if he planned to use it for the Auto Italia race or not, but it was parked by his transporter with the panels off so I could see the injection setup.

This was installed with what looked like some short trumpets with foam sock-type filters over each intake. These probably didn't come up any higher than the normal plenum chamber, or certainly not far off that height. I don't know if the trumpet came to the top of the filters though, which would mean no margins if height is restricted.

From the rear, it did look as though the engine installation might have been lower than on the Hawk HF3000 and on some of the other V6 conversions. I got this impression from the visible angle of the driveshafts, which went up at their outer end by a noticeable amount. On my car, the driveshaft tends to run near horizontal.

This isn't a clear indication though, as I run my car higher than his, so maybe it was just an effect due to this Corse being set up with much lower suspension settings. As the chassis is totally different to the Hawk, I cannot compare the position of the engine in relation to the chassis members, so maybe the engine heights are the same.

David, I guess that something else is also different on your car, as you have needed to make clearance for the V6 plenum chambiner in the rear body panel. This may be down to either your particular engine installation or maybe just the body panel fitting coming out different on your car. As you've needed to make this extra clearance, I suppose you have even more concern about space used by the throttleb body injection setup.

You could always try raising the rear panel at the hinge mounts, although that would lead to misalignment on the front edge where it meets the tub, so that's not going to be ideal. It would also look odd if the panel ends up with a 'tilt' when viewed from the side. Just thinking 'out loud' though.

Final comment - Graham did win the Auto Italia race, against another four Ferraris from the other series. Did look like two completely separate races though. I should also point out that Roger was in this race, in his Alfa 33, so he may have some comments as regards racing against the Ferraris.

Cheers all,

[Stratos]

John,

I was also there on Monday. Wish I'd known you were down.

Basically, I echo your comments entirely, and respect your winge -I think it's a very valid point. Still when your new car hits the tracks, you'll hopefully be able to show them all the way home!!!

Looking at the installation in Graham's car, I think most hawk and Corse owners should be able to use a similar setup.

Regarding engine position. I too noticed the angle of the driveshafts on Graham's car. I'm sure that when I have looked at the V6 in Gary Lomas's Corse S his driveshafts are pretty much horizontal.

The chassis in my car(Allora) is very different to the Corse S, and I can't get the engine down low enough because the sump fouls on the chassis rail - that's why I had to remove the piece of bodywork behind the louvres to make space for the plenum chamber and breather pipes. When I converted to the Omex Mappable ECU, I removed all the breather system, and now just have the engine breathing to a catch tank, so there's a lit bit more room there.

I don't have any plans to put throttle bodies on this car. As it's about 100kg heavier than a Hawk or a Corse, and the chassis isn't as strong in certain areas, I think it's reached the limits of it's development.

My interest in throttle bodies is currently academic - at least until I get started on the Corse S which is presently sitting on the driveway.

[roger001]

As John mentions I was in the auto italia race at castle Coombe, Interestingly Graham Scott arrived in the assembly area in His Corse, however it had been raining on and off in the previous practice sessions and while waiting for our practice the rain started again, it was at his point he left and changed to the ferrari - maybe he preffered it for a wet session.
The wet suited me and I was able to out qualify Neil Smith's Uno for the first time, and consequently (Due to the reverse grid arrangement) started in pole position for the first time, this made the drag down to quarry interesting as a 1500 alfa 33 is no match for a F355 so we (Neil and myself) arrived at Quarry at the same time as a Minari and 3 of the F355s ( four abrest will not fit at Quarry so it was a case of trying to avoid contact and come out the oter side in one piece) two went past before the bend and one between the bend and the subsequent esses, after that It was Bye Bye ferrari as they vanished into the distance.
This left me to see if I could do any thing about the gap neil had opened up about 150 m, I felt I was gaining slightly but not enough, then an Alfa GTV dumped the contents of its sump all the way from the second esses to the entry to the fast corner at the begining of the start finnish straight, which meant taking a slower line into this bend. I was unable to close the gap any further and finished second in class. Graham understandably won the event

There was an interesting philosophy in a recent MSA magazine about Auto italia first corner policy it reccomended "adopt 360 degree vision and pray"

[Stratos]

Roger,

It was nice to meet you down there, and have our little chat.

I took video of the whole race. Guess what? - you feature quite heavily in my footage. I'll copy it onto a video and send it up to you - send me a PM (Private message) with your address.

I was disappointed that there were no Stratos in the race - that was the whole reason I travelled all the way down to Castle Combe. I had hoped to use the video footage on Saturday evening at Abingdon. Supposedly, there was going to be Graham Scott in his Corse S, and Hennessy Racing were also supposed to be running their Stratos Evolutione. So slight change of plans on the video front for this coming weekend.

[roger001]

Well done - my son tried to take a video from Quarry but apart from six cars+ all heading for the bend together on lap one, there is not much else to see as his technique needs nurturing!

[Matt P]

the reason the graham scott did not use his stratos at combe was he preferd to drive the Ferrari.
the drive shaft and rear lower wishbone angles are a big problem on that car if he got it sorted it would handle even better. the problem it has is that you can not raise the rear wish bones to lower the car as they would hit the drive shafts. due to this in bump the car actualy goes into posative camber. just to note all the other suspension and stearing mounts on this car have been raised on the chassis to lower the car. the tick with the rear suspension is in the engine mounting. you must use a 155 2.5 sump and oil pump and rotate the engin forward, which in turn raises the drive shaft line.
hope this helps
matt.p

[Stratos]

Matt,

Are you saying that this is something Graham Scott has changed since acquiring the car?

or

That it was a problem which existed when the car was run by Hennessy racing?

or

That it is a problem with the suspension pickup points on the Corse S chassis in general?



I was looking at Graham Scott's car when it was parked up at Castle Combe, and I actually noticed this fact. His driveshafts point downwards toward the centre of the car. Most of the other Corse S V6s I have seen have their driveshafts pretty much horizontal.

[rutthenut]

Matt,

That's an interesting description of the suspension problems on that particular car. I'd also seen that the driveshafts do run at quite extreme angles on Graham's car. I've also heard of it breaking driveshafts on quite a few occasions, which I don't think it seemed to do when Tony Soper/Chris Snowdon/Hennessy Racing used to run the car - so maybe he has lowered it 'too much'.

The problem with the strut suspension going into positive camber in bump is certainly not ideal. Putting in more negative camber when static can only help to a certain degree, before causing problems with straight-line grip.

If there is not room to raise the inner points of the wishbones, the other option to consider is the use of longer wishbones. That means more work on chassis alterations though, so is not a simple modification. But with a longer wishbone length, the outer end has less effect on the strut camber angle for the same given amount of angular travel on the wishbone. My 'lightweight' chassis has this mod for this particular purpose, but that is not exactly near to completion. I also thought it would be more use as a theoretical improvement than in practice, but maybe it will be of more benefit than I had thought.

I also hadn't heard about using a different sump on the engine.
That may be a useful tweak for the rally guys if it allows for more clearance without necessarily changing the position of the engine.

Cheers,

[Matt P]

the problem on grahame scotts car has always been there since we lowerd the car. i currently runs over 3 Degs of negative on the back and still manages to go in to posative camber.
The reason it now brakes drive shafts is that they dont change them often enough. when we ran it in GT's we changed the or at least checked them every two meetings. the other problem is grahame has done about three seasons of racing and testing in one year with the car. so make your own mind up. the rear suspension also does not help as the shafts can run out of movement causing damage to the joint and shaft.
As for running it to low well yes they do about 1/2" to low to what we originaly had it set at. but hay i only worked on it for years what do i know.:D

[rutthenut]

Originally posted by Matt P
The reason it now brakes drive shafts is that they dont change them often enough. when we ran it in GT's we changed them or at least checked them every two meetings.

Matt, does/did this car use standard Beta shafts, or are they modified in any way? Also, did you spot driveshaft damage or cracks appearing in any way and hence catch the fault before it failed when in use? Or did you use a crack testing fluid of some sort?

I gather that John Whalley has used Delta HF Turbo driveshafts on cars he has built (although not used in competition) but I think that they needed some machining to fit in Beta hubs. He probably uses different hubs too, just to confuse the issue.

I know that 5-stud Integrale hubs can be used, along with different (Delta?) driveshafts, which is the route suggested for those who want the five-stud arrangement and the option of using Alfa 164 brakes on the car. For cars with driveshaft weaknesses, this may be a further reason to look at these parts.

[Matt P]

john,
I used to crack test the shafts and check the joints every two meetings. but alas yes it still runs beta shafts (boho). the car is crying out to be sorted.
As for using other shafts there are loads of hubs and shafts you could use. tony favarin and i have looked in to using 164 and 155 parts mainly because there are a few in the scrap pile now and we are alfa bias. But always remember big tyres more grip more grip more built up torque in the shaft. more torque requires a biger shaft.

i must say if i ever see a lancia beta drive shaft again i will do somthing i regret.