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Richard Jemison
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Here`s some comments based on a quick read through of the thread:

Brakes:
Front brakes from GTV6/Milano when set up correctly with proper race pads, are more than adequate for endurance racing.
This means true forced air cooling from either front vents in the airflow or use of marine type bilge blowers to cool. As well correct brake fluid with 600 degree dry boiling rating typically ends soft petal. The most effective method of keeping pad heat out of the fluid (and pistons conducting it there) is to use .040 thick stainless sheet metal spacers cut to pad shape between the pads and pistons. Actually a pair of these on each piston is very effective as stainless does not conduct heat well surface to surface.

Rear brakes:
Loose the Alfetta/Milano design calipers as too much metal in the units and overheat with little use. Simply swap to Spider calipers with stainless insulators as above and proper brake fluid.
Venting effectively is needed. Winglets welded to the deDion tube forward of the brakes to scoop up air into the dead space around the brakes and TA will help more than anything else. (also cools TA) Similar winglets can be used on the 105/115 cars to improve rear brake cooling
Venting through the side window gets very little if any air. (Too much turbulance for "NACA" type ducts to get any result. If that is your choice then you will have to force air with blowers.

Suspension:
Front, the best handling modification are dropped Spindles that not only lower the car but improve the suspension geometry by increasing camber gain on bump and reducing it on droop, and raising the roll center all of which reduces understeer.
High negative camber settings (2.5-3+) will only kill tires. Not a minor issue in endurance racing.

Rear:
The dedion is an "Active" type suspension. Reducing that a bit helps.
Move the front mount of the triangle up as much as possioble by removing the shims between the cross member and chassis body. (put the shims between the bolt head and crossmember to take up length (or use washers about the same thickness) as the threaded section of the bolts will be too short and strip the internal threaded plates.
Also move up the front deDion bushing to the top of the cross member to further raise the pivot point. This will make the car far more stable under braking and stable on turn-in.

Easy way to get some negative camber on the crossmember, weld a solid bead along the top of the deDion tube. this will pull about -.75 degree on both sides. It will also stiffen the flimsy tube a bit.

Hubs etc:
The Alfetta type upright has a smaller outer bearing than the V6 (5 stud) type upright. Otherthan the spindle, they are the same dimensionally.
Vented brakes are larger in diameter so when converting the cast iron brakes (either ATE or Iron Brembos) from the Alfetta, to Aluminum Brembos the brembos will need to have the mounting holes slotted so they can be slid closer to the spindle centerline so that the pads don`t overlap the brake disk.

Driveline:
If you are breaking clutch covers it is a result of the rear section of the driveshaft not being centered and stable as Greg has pointed out.. That is why my design for one piece driveshafts used the front spline section from the Milano/GTV6 (for adjustment) and only used the late Alfetta rear guibo as it is the most positive centered one made. If the centering nose section of your clutch input shaft os worn or buggered, replace it or it can be hardwelded and machined (and actually be made longer to center more effectively.)

I have many Brembo caliper spacers. ( FYI:They can be used on ATEs as well) Email or PM me.
 

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Cam belt Tensioners

Warning Long Post.

This year I have had a lot of problems with my Milano in lemons racing. The
first race of the season the head gasket gave up (original). No damage but that
entailed some work. I took the opportunity to cut the head(.024") and lapped the
valves and uprated the valve springs (30% stiffer). It all went back together
well and based on my seat of the pants dyno I was up some noticeable power. The
cam in this car is a used one I found on eBay an RJR 570/744 it works very well in my
motor. Leak down on the motor has always been really good (2% to 6%)

As some of you may know I have the rev limit set at 7200 and a set of used eBay
IAP headers that we welded a balance pipe to. The pipes go into a gutted center
section muffler and then two pipes out the side. I replaced the plenum AFM hose
with a big smooth hose going to the AFM and a cold air feed to a KN style
filter. The motor is tuned pretty well, cam timing optimized. It's was on a
Chassis dyno 3 years ago and it had plenty of fuel for what it could breath. For what its worth the dyno said 145HP and I think about 140 ft/lbs of peak torque before I worked on the heads. But most
importantly we drive like we stole it. The harder you drive it the better it
runs and believe you me, I hammer this motor hard.

So back to the problem: It's all about the mechanical tensioner's. Six hours
into the race at NHMS the outer spring in the tensioner fatigue cracks and we
lose some tension it skips and its game over. OK, Now I do a proper valve job
with guides and new valves and I am getting good at this. I bought a NewWay kit
and port match and some other work as well. Remove some pistons and inspect the
bottom end everything looks great. So I put it all back together and while I am
talking about getting a hydraulic detensioner I cannot locate one in time for
the race at Summit point. So 5 hours into that race one of my drivers hears a
pop and bang and the power goes away and the car is smoking a bit. We bring him
in and after a bit of jerking around I see the 1,2,3 bank cam is out of time by
one tooth. Sure enough the new mechanical tensioner outer spring is broken. So
we pull it apart screw the tensioner together and reset the cams and send the
car out. The powers OK but the car is smoking blue smoke pretty heavy and I
decide rather than grenade the motor better to retire.

BTW I am tensioning with a fixed tensioner so that the belt along the long length on the tension side
can not quite be turned 90 degrees, you agree?

So it turned out, I had a few bent valves on the 1,2,3 bank and the bent intakes
valves had pulled my guides out on 2 cylinders so oil was leaking down the bore
the valve guides press into. Fast forward and I have repaired the damage.

It seems as though the little bit more of spring rate on my valve springs has
changed things radically for the mechanical tensioner. It is being rocked around
with some sort of resonant excitation which fatigues and cracks the outer spring
that goes to the bimetal element. So I need to tension the belt differently. I
see a few choices.

1. Wind the mechanical tensioner up to it installed position and use 5mm bolts
through the blind holes in it to turn it into a fixed tensioner
2. Use a rebuilt hydraulic detensioner which I have.
3. Use the hydraulic detensioner with the oil feed port block off so there is no
detensioning.
4. Design and build my own fixed adjustable mechanical tensioner using the
plastic wheel and bearing from the stack of used tensioners everyone has.
5. Take the hydraulic tensioner apart and tap a thread where the piston assembly
is now located for a pusher screw.
6. Attempt to make a ZAT style tensioner, probably the most work to do it
correctly.

Perhaps I missed something? Anyway I am spamming a few people with this message
to see if the collective wisdom can help me and also cross posting this. I have a few photos I cut & pasted of some examples of other peoples tensioners.




Links to pictures or instructions on other sites are also welcome.

We are racing at NHMS in Loudon NH on October 26th through 28th if any Alfisti in New England
want to stop by.

Thanks in advance.

Greg
 

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My LeMons/Chump Milano is up for sale, the car has a 100% finishing record, has run LeMons, Chump, ECTA, and THSCC Rallycross. The car is available by itself or in a package with my Grassrrots challenge GTV6 with fresh Difatta heads, and a Milano Platinum street car currently on the road.

3 cars and spares $3500
Just the Chump Milano $1500

Spares include brakes, shocks, ecu, AFM, doughnuts, trans mounts, etc etc.

Wheels in the package are 1 set GTV6, 1 set Stil Auto, 5 Verrde, set of Wine glass/Platnium.

Located in Eastern NC

Thanks

Al Taylor
[email protected]
 

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My LeMons/Chump Milano is up for sale, the car has a 100% finishing record, has run LeMons, Chump, ECTA, and THSCC Rallycross. The car is available by itself or in a package with my Grassrrots challenge GTV6 with fresh Difatta heads, and a Milano Platinum street car currently on the road.

3 cars and spares $3500
Just the Chump Milano $1500

Spares include brakes, shocks, ecu, AFM, doughnuts, trans mounts, etc etc.

Wheels in the package are 1 set GTV6, 1 set Stil Auto, 5 Verrde, set of Wine glass/Platnium.

Located in Eastern NC

Thanks

Al Taylor
[email protected]
Yes, yes thats great.

But the question I have is....

What kind of tensioner does it have? :)
 

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Well, here I am, getting ready for 24/25 hours of Lemons, Sonoma Road Course will be our first run next March I expect. Need a car, I am thinking:

1) AR GTV-6
2) AR Milano
3) Maser Bi-turbo
4) 83/4 Mazda RX-7
5) 74 Porsche 914 2.0
6) AR Alfetta GT

I have 4-5 team members, enough?

ncng
Just saw this.

4 drivers is fine for a normal race. If you want to be competitive, then you'll want to start running longer driving stints, 2+ hours. Once you get to that point, 3 drivers is all you need for the normal events, 4-5 is good for a 24 hour race.

If I had to choose an Alfa I'd go with a GTV6 (we're running a Milano). I think you can get the same performance as a Milano, relatively speaking, with a lower center of gravity.

bs
 

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Greg,

I've never seen a Zat tensioner until doing a timing belt and water pump in my daily driver Platinum a few months ago. It has one. I wouldn't hesitate to use it in a LeMons car.

In my street GTV6, with a 3.0 and Jemison cams, we put a hydraulic tensioner back in place of the old mechanical tensioner. Just blocked off the oil feed hole.

In our LeMons Milano, we're running a mechanical tensioner. But we don't rev the pi$$ out of our motor like you do. Our optimal shift point is around 5700 rpm, and if I'm conserving fuel I'll shift below 5000 rpm. 13+ races on the car, we've never had a tensioner problem.

I wouldn't hesitate to use a fixed tensioner. We also run straight 50 weight oil. Once these cars are up to temp, they run 99% of their time under those conditions. So all of the benefits of the oil feed, springs, etc, is mostly wasted on a race motor. You're not daily driving your car on a cold New England morning, so dump all that crap and simplify things.

The real solution is to toss the 2.5 and throw in a 3.0 motor.

bs
 

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Tensioner?

Dont know...but the one on the GTV6 should be about 5k miles fresh...F.unny thing is the race car was out in the weeds so long I could not remember wehre it came from, pulled the tank, replaced all the rubber hoses, changed the oil and went racing. Shoulda got some better pads for that first race. The car must have had a fresh belt, WP, guibo's and mounts when I got it. The GTV6 just had the heads done when I got it, WP went out down in FLA for the grassroots thing, does not make sense. Why would a shop do the heads and not replace the WP??

Never had any tensioner issues but everything is stock, might be like the old BMW's I race if you take it just the tiniest bit over stock you break a rocker arm.


Al
 

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We just completed the ChumpCar double 7 at Road America. We managed to make it to the checkered both days, but barely. Here's the list of problems with our 2.0l Alfetta:

Disappearing brake pedal- rear brakes failed to stay adjusted. Plan to switch to Spider calipers.

Charging system failure- lost the voltage regulator at the same point in both races. Not sure how to proceed

Exhaust manifold tried to depart company with the engine. Lost 6 of 8 nuts. Added to the list of things to torque after the race

Miss fire and loss of power- at least partially related to the charging system failure. Low voltage followed by burning the points after hot wiring the alternator.

Dirty fuel tank- We had problems with clogging the pre pump filter earlier in the season. Removed the tank, cleaned it, re plumbed it with a 1 qt spin on filter. Checked the filter after the Saturday race and guess what we found.

Everything else worked as advertised. When the car was healthy it was a blast! Our hot shoe driver managed a 3:17 with the bend.
 

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Greg,

I've never seen a Zat tensioner until doing a timing belt and water pump in my daily driver Platinum a few months ago. It has one. I wouldn't hesitate to use it in a LeMons car.

In my street GTV6, with a 3.0 and Jemison cams, we put a hydraulic tensioner back in place of the old mechanical tensioner. Just blocked off the oil feed hole.

In our LeMons Milano, we're running a mechanical tensioner. But we don't rev the pi$$ out of our motor like you do. Our optimal shift point is around 5700 rpm, and if I'm conserving fuel I'll shift below 5000 rpm. 13+ races on the car, we've never had a tensioner problem.

I wouldn't hesitate to use a fixed tensioner. We also run straight 50 weight oil. Once these cars are up to temp, they run 99% of their time under those conditions. So all of the benefits of the oil feed, springs, etc, is mostly wasted on a race motor. You're not daily driving your car on a cold New England morning, so dump all that crap and simplify things.

The real solution is to toss the 2.5 and throw in a 3.0 motor.

bs
I wound up modifying a hydraulic detensioner to make it into an adjustable fixed tensioner. I got some good advice from a few people. IAP and others sell the robust bearing that goes on that tensioner so it has a new bearing. Jason at Alfissimo has bearings and rebuild kits.

Funny thing is that I have been driving this car balls out for 4 years on the valve springs and other stuff it came with when I found it parked on the back lawn of the guy I bought it from. I tuned it up and it never ever let me down until 4 years into racing it, when a 22 year old head gasket began to leak a little.

So I think all the people who couldn't believe that we shift at 7000 + RPM all the time for 4 years telling me I was going to valve float a valve into a pistoon finally got to me and I uprated te valve springs,

But the 2.5 Liter has smaller lighter valves than the 3.0 liter, this was an unecessary modification that cost me two DNF's and a lot of bent valves and work. For the record I think the mechanical tensioner is OK for a stock street car, or you can adjust it all the way to take the spring out of the picture for a fixed action or go some of the other ways people have done. Belt technology has come a long way since the 1970's whem Busso designed the engine and detensioner.

So Brian, I geuss I should have just left the old springs in and run it no? But you know my middle name is Greg "f%&k with it" Seferian.

Greg
 

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Hey Guys

Even while trying to unload a bunch of my V6 stuff including my LeMons/Chump roadster I acquired the #27 "slammer" orange Milano LeMons car...it is much nicer than my current car and has lots of fresh parts. I plan to run it at the CHump VIR and Charlotte races.

I have so much V6 stuff it only makes sense to burn it up on the race track. The old "Black Barf-Cheddar" will be used for local rally crosses until something major breaks on it.

Anyone else planning to do the VIR races, my shop is 4 miles from the track and I have parts cars there....


Thanks

Al Taylor
 

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Hey Guys

Even while trying to unload a bunch of my V6 stuff including my LeMons/Chump roadster I acquired the #27 "slammer" orange Milano LeMons car...it is much nicer than my current car and has lots of fresh parts. I plan to run it at the CHump VIR and Charlotte races.

Anyone else planning to do the VIR races, my shop is 4 miles from the track and I have parts cars there....
Hi Al,

Which Milano is the car you are talking about? Is it those guys that were running it at CMP?

Are you going to do LeMons at CMP or just Chump?

Greg
 

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The car ran CMP and Charlotte I believe. I only run Chumpcar...along with SCCA NASA SVRA etc...Lets just say I had a disagreement with Jay Lamm, who is a pretty good promoter but not much of an engineer.

Yall need to come down to VIR.

Al
 

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Anyone here running a 3.0? I am about to pick up a bunch of spares....might drop a 3 liter in next but I think would make sense to burn up all my 2.5's and sell off the "good" motors...Anyone running Motronic? I cruise a lot of junkyards and can pick up 164 parts pretty reasonably.

Al
 

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I have had a 3.0 liter S motor on an engine stand for a good 2 years now. I need to open it up and take a look around in it. But it is really hard to give up on my 2.5 liter motor in the LeMons Milano when it can run with everything except the big V8's and the turbocharged cheaters.

That said, there is no replacement for displacement...

I am just not looking forward to the new engine note when we have so many track workers coming to our Pasta parties and telling me " your car is the best sounding car out there" "Its awesome"

Greg
 

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Anyone here running a 3.0? I am about to pick up a bunch of spares....might drop a 3 liter in next but I think would make sense to burn up all my 2.5's and sell off the "good" motors...Anyone running Motronic? I cruise a lot of junkyards and can pick up 164 parts pretty reasonably.

Al
We are running a 3.0. I wouldn't waste my time with a 2.5. We've drag raced Greg Sef once or twice, I think the cars are fairly close, but I can also tell you that we're shifting at 5000 - 5500 RPM, and he's revving the bejesus out of his 2.5 (which I will admit is the best sounding LeMons car ever, east or west coast).

Greg drove our 3.0 once, and the best comment when he got out of it was "that rev limiter was effing killing me".

Couple of points of reference for you. First, the transaxle. We started life with the 3.55 limited slip. The 2.5 Milanos with the 4.10's could out drag us. When we swapped in a 4.10, we could for the most part out drag them. But we sacrificed mileage. With the 3.55 on the right track we could drive over 4 hours. With the 4.10 the most we've seen is 3:15. The car is more fun with the 4.10, and faster, but I think we'd be better off with the 3.55 and longer driving stints/less pit stops.

Second, the motor. We can go pretty fast and not push the 3.0 too hard at all. We've left in the stock ECU and rev limiter. In 5 years and 15 races, we've had *one* catastrophic engine failure, and that was a fuse/cooling fan problem that led to overheating. I'm pretty sure that motor would still be running if not for that fuse. Our second motor is holding up just fine since 2010, and probably 8-9 races. I've never so much as looked at a spark plug.

hth,

bs
 

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hmm...I have running 2.5's in each car and one spare with fresh heads....will probab ly be a while before I could swap in a 3L so I probably should just sell them.

I have to check out the rules, I thought the longest stint allowed was 3 hrs, I may be confused, would be nice to do the VIR 10 hour with 2 stops. Not sure what trans is in the orange car, will have to check that out.

Sound...yes, one of the reasons I continue to own V6 Alfa's. The exhaust needs work on the orange car, what set up do you guys use?? I would like a side exit to keep things out of the way in the back...


Thanks

Al
 

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Discussion Starter #57
Driving stints

I have to check out the rules, I thought the longest stint allowed was 3 hrs, I may be confused, would be nice to do the VIR 10 hour with 2 stops. Not sure what trans is in the orange car, will have to check that out.
Al
Driving stints in Chump can't be more than two hours according to the rules. That and the mandatory 5 minute fuel stops are the big reasons we haven't run with them. We can run three hours plus on fuel (depending on the track) and can fuel the car in under 2 minutes. Take that away and you take away our big advantage and we have a hard time running with them on power with a stock 2.5 motor.
 

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Interesting.....allowing longer stints evens the playing field as far as power goes...of course then people with juice will rig in a 35 gal cell....I won a NASA endurance season championship on mileage....used one less gallon an hour than the other team and that is all it took, well really came down to the fact they had to change pads in an 8 hour race and we didn't...seems like they would allow 3 hour stints as the less time in the pits the safer it is for everyone.


Al
 

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Discussion Starter #59
Lemons rules limit the fuel cell size at 24 gallons. I know that you had some differences with Jay but almost all the rule changes lately have been safety related and driven by the Insurance company. If that is what it takes to keep the series alive then so be it. At least I have a relatively cheap place to go racing.
 

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Miss fire and loss of power- at least partially related to the charging system failure. Low voltage followed by burning the points after hot wiring the alternator.

Did a leak down on the engine today, results were not good. Pulled the head and the pistons, found broken compression rings on #2 and #4. I think I found the power loss!
 
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