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02-01-2008, 02:08 PM
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Richard Jemison
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Join Date: Apr 2005
Location: Pensacola, Fl. U.S.A.
Posts: 799
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Cam info;
Actually the cam doctor #`s for the "S" measures max lift at .3874 not
.398, dur at .050 of 233 and lobe separation angle of 111.25 ??? 
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
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02-02-2008, 09:59 AM
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Join Date: Jan 2007
Location: Illinois
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Interesting. AR pub displays Intake cam lift at 10.1(.396) so I guess the Italians round down (10.1mm =.3976 by my calculation or .398 rounded up as in your exhibit). So, the "S" cam you scoped with cam dr. was actually 9.84mm lift? What a jip!
There's been discussion about the revving characteristics and sound differences between the 2.5 and 3.0 12V motors. Some of this might be due to the displacement differences, but I think it's mostly due to the cam and final drive differences. (slap 2.5L cams and a 4.10 in there and I bet the 3.0 will rev like the 2.5!)
I've owned both and and prefer the 3.0 12v in the Verde. Though, with the Platinum 4.10 it would be something off the line! On the other hand, It's more relaxed on the highway.
Last edited by ToonRboy; 02-02-2008 at 02:33 PM.
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02-02-2008, 10:50 AM
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Join Date: Jul 2005
Location: Oslo, Norway
Posts: 459
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--------------left cam:------------------------right cam---- in millimeters
height--------37,59-----37,59----37,61---------37,47---37,48----37,48
width---------27,65-----27,65----27,67---------27,53----27,55---27,55
lift------------9,94------9,94-----9,94------------9,94-----9,93----9,93
Measuments I made before installing SZ cams in my GTV 3.0 Same stock numbers as the US S.cams.
These cams have been tried here in a 2.5. It was reported some loss in bottom power, however it revs very freely on top, just like in the 3L.
Also here there has been believers that the 2.5L revs better than the 3L, but that is from people who had been to much on the internet and no own experience. The 3L feels much better to drive and revs just as well! 
The data lists submitted above seem to be correct as far as I have checked, unfortunately too much in and thous, so I have to calculate everything to get understandable values
Last edited by Gabor K.; 02-02-2008 at 10:59 AM.
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02-02-2008, 03:22 PM
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Registered User
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Join Date: Dec 2004
Posts: 310
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 Quote:
Originally Posted by Greg Gordon
I have put the Autodelta instuctions for building a 200hp V6 back on my site at Performance Page . These are instructions from the real Autodelta, which was a performance division of Alfa Romeo, not to be confused with the UK based tuner that has latched onto the name.
Greg Gordon |
~Benjamin
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Daily Drivers
-'91 Alfa 33 series 3 16v
-'90 Alfa 164 3L 12V
Projects
-'82 Alfasud Ti mid-engine Alfa V6 project coming soon!
For Sale
-'82 Alfetta Sedan - in bits, take me, I'm free!
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02-03-2008, 08:57 AM
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Richard Jemison
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Join Date: Apr 2005
Location: Pensacola, Fl. U.S.A.
Posts: 799
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V6 cam info
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Hahaha - you funny! Much like the soup nazi in the Seinfeld series. "arrgh, no soup for you!"
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On the Sg website spread there are some #`s out of place. I hadn`t cought them but my webmaster is a friend and I try to keep changes minimal as she provided this gratis! The out of place & obvious "S" cam`s duration #s for one. The #28 cam profiled is actually the RJR 28+5 cam which adds 10-12 degrees to the upper lobe of the cam. This is not the 28 grind being noted as West Coast "E" friendly.
When a builder has the capapability of spreading a lobe to get more duration from it in the middle & upper lobe there are nice bebefits. The results can best be described by immagining having two cutouts of a full lobe profile. If you overlay them, then stick a pin through both at the basecircle`s center, and separate the lobes at the top by 2 degrees (or whatever amount) you can see the growth in the lobe profile. The profile will expand more in the upper areas, diminishing as it gets closer to the centerline, resulting in no great increase in overlap. The growth will be on both sides of the lobe so duration will be increased at the upper areas by 2x the amount of spread initiated (4). The grind will then be described as a (for instance) 28+5 (10).
Of course this is a US industry standard and ToonR will want it converted to Brittish Standard fer sure)
And for TuneR`s edification, I have never bothered with converting all that foreigh data to US Std. Why? It is lobe profile that matters. ("It is the Lobe stupid!) Why don`t they publish there`s??? Why don`t you contact them at their sites provided and ask them. God! I love stirring sh*t !!
I`ve tried to download some pictures of the Valve seat cuts, bowl cleaning, valve shapes but my images are too "large" to attach. Any one know how to smallify them? Email me, PM`s are a pain...
I`ll attach a pic of the correct setting up of a pair of race cams. I will say this up front. On smaller HP street cams this is hardly necessary. But testing/measuring valve to piston clearance is critical in all cases. Using a plastic wire tie of .075 to .090 exhaust and .040-.050 on the intake side
slipped through the sparkplug hole can save a motor.
I swear I`ll get back to where we left off on the heads when I have more time.
The adjustable sprockets allow infinite corrections of cam timing, absolutelly necessary when the decks are shortened, heads milled. belt stretch etc. and belts do stretch, not much after the first serious run or 1000 miles, but race cams need constant attention to this as correctly designed cams leave little clearance to play with when designed to fit...
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
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02-03-2008, 09:32 AM
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Registered User
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Join Date: May 2004
Posts: 2,109
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Benjamin, my site will be back up on Monday,
Greg,
www.hiperformancestore.com |
02-03-2008, 09:58 AM
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Join Date: Jan 2007
Location: Illinois
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That de-tensioner looks like it's been modified (to be a manual tensioner). Very nice.
I say this because when I was reading the webcam's "Degreeing in your camshaft" article, Web Cam Inc - Performance and Racing Camshafts to determine true TDC, it says "Install your positive stop device into the spark plug hole and extend the bolt. Now hand turn the engine, rotating it until the piston comes up and stops against the piston stop bolt. Look at the degree wheel and write down the number of degrees shown by the pointer. Hand turn the engine in the opposite direction until the piston comes up and stops on the piston stop bolt again. Go back to the degree wheel and write down the degrees it now reads. Add these two readings together and divide the answer by two"
The reason I bring this up is because so many Alfa V6's have the mechanical de-tensioner unit installed & turning the crank counter-clockwise is not advised. Alfa 164 TSB 01.93.04
Oh, and thanks for those lines posted for my edification - most helpful. One thing I can say for sure. Hypocracy holds no bounds.
Last edited by ToonRboy; 02-04-2008 at 07:26 AM.
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02-03-2008, 10:43 AM
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Join Date: Oct 2004
Location: Columbia SC
Posts: 1,246
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It looks like a Zat tensioner. I have one on one of my Verde's and I would like to get another to replace the mechanical type on my second car. Tom Zat recommends adjustment after 15k miles and replacement of the belt at 30k.
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Ed Prytherch
79 Spider Veloce
88 Milano Verde
88 Milano Verde
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02-03-2008, 10:51 AM
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Registered User
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Join Date: Jul 2005
Location: Oslo, Norway
Posts: 459
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"Hand turn the engine in the opposite direction" Ha-ha that was a real expert to listen to! Never turn the engine the opposite direction regardless of what kind of detentioner you have! Thatīs really basic!!!!
Last edited by Gabor K.; 02-03-2008 at 11:21 AM.
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02-03-2008, 03:25 PM
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Senior Member
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Join Date: Oct 2004
Location: Columbia SC
Posts: 1,246
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Ok Gabor. Please explain why turning the engine backwards is risky with a fixed tensioner.
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Ed Prytherch
79 Spider Veloce
88 Milano Verde
88 Milano Verde
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02-03-2008, 04:22 PM
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Registered User
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Join Date: Jul 2005
Location: Oslo, Norway
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A good reson is that the factory manual advises to avoid that! You must always turn the engine the correct way!
The reason for this is with the hydraulic detentioner the belt will be slackened and belt can jump over and there is possibility of contact.
With the mechanical detensioner the problem is it does not take up slack. After some use and lenthening of belt a reverse turn could result in the same.
Matter of fact the mechanical detensioner is way overrated. In a case here the belt jumped over 2 teeth in a newly assembled engine, and torqued tensioner. The engine barely survived the contact betw. valves/pistons!
Well, better play safe and follow factory standards of work and a lot of problems are avoided!
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02-03-2008, 05:04 PM
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Senior Member
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Join Date: Oct 2004
Location: Columbia SC
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Gabor:
You have not answered my question. This is a FIXED tensioner. We all know that belts can jump with the hydraulic and spring loaded tensioners. This is not one of those. It was designed and manufactured in the USA to avoid this problem. Maybe they never made it to Norway. Here is a challenge: Find someone who has had a belt jump while using a Zat fixed tensioner.
__________________
Ed Prytherch
79 Spider Veloce
88 Milano Verde
88 Milano Verde
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02-03-2008, 08:14 PM
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Richard Jemison
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Join Date: Apr 2005
Location: Pensacola, Fl. U.S.A.
Posts: 799
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Zat designed tensioner
the fixed (but adjustable mechanical tensioner Tom designed years ago is the best of the bunch. PERIOD" the BS about block growth is a myth as far as belt tensioning goes. For goodness sake! Don`t believe all the bullsh*t you read regarding this stuff. I only use ZAT type on my racecars.. No slack no jump! Spin off the track, see if your motor doen`t spin backwards.
The next bet is the later mechanical tensioner tightened to the point it can`t back off. Check every 2500 miles to tighten..
The oil pressure detensioners should be in the trash, other than the base & bearing to make a ZAT copy!
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
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02-03-2008, 09:50 PM
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Registered User
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Join Date: Aug 2004
Location: Portland, OR
Posts: 489
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Quote:
Originally Posted by alfaparticle
Gabor:
You have not answered my question. This is a FIXED tensioner. We all know that belts can jump with the hydraulic and spring loaded tensioners. This is not one of those. It was designed and manufactured in the USA to avoid this problem. Maybe they never made it to Norway. Here is a challenge: Find someone who has had a belt jump while using a Zat fixed tensioner.
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I like the idea of the Zat tensioner. But, I ordered a Zat tensioner 5-6 years ago. The quality was terrible. The shaft that held the bearing was not at a perfect right angle to the face of the base plate and hence the belt wandered slowly off the pulley as I cranked the motor over by hand. I figured out what was going on, took it off and checked the angle. I sent it back. They sent me another one. Same problem. In the trash it went. I was really disappointed. I liked the simplicity and had never heard of anything going wrong with one. Admittedly many fewer users, but still no bad stories. But the execution was horrendous. I hope it has improved since then.
Karl
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Have: 1969 1750 GTV under restoration
1969 1750 Berlina
1968 Giulia Sprint GTV (very rough, no motor)
Had: 1982 GTV6 3.0 w/4.10 rear, Stebro (imported engine from UK in 2002) -- Rear-ended 8/2004.
1988 Milano Verde
Non-Alfas:1984 Volvo 244
Last edited by karmat; 02-03-2008 at 09:53 PM.
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02-04-2008, 06:48 AM
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Richard Jemison
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Join Date: Apr 2005
Location: Pensacola, Fl. U.S.A.
Posts: 799
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Tensioner not detensioner
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A good reson is that the factory manual advises to avoid that!
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You think maybe it was because of the designs they tried to make work???
The fixed tensioner in the picture is a Zat unit. It can not back off. You can turn the motor backwards no problem. It it the only "safe" type of tensioner.
But, if you tighten the mechanical spring type to the limit of lever movement it can`t back off enough to jump time either.
The old oil pressure type units are a real hazard to the motors. Run them at your risk.
As to turning motors backward in cam timing, thats done as a norm .
Gabor, you need to "STUDY UP"! Or don`t type your lack of knowledge on these things that you are "behind the curve" on, so the rest of us know how little you really know!!
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
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