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Discussion Starter #1 (Edited)
Hi.

I am looking for a set of new camshafts for my SPICA engine. I have read numerous threads on this topic but they are either so old that the cams in question are not available any more or they all end with "use euro cams".

I already have "euro cams" installed in the engine. I am looking for something hotter but still works with the stock pump. I want something that is good up to 6000 rpm. Not looking for a screamer.

The engine was restored a few years ago (it has run less than 3000km since then).
The top is very mildly ported. Mostly cleaning up the intake and exhaust channels and at the same time removing any lip on the intake manifold and exhaust.

It has Borgo 10.4 pistons and the stainless exhaust from Alfaholics, including their headers.
And currently 10548xxx standard 2000 euro camshafts.


Have anybody tested centerline 11.1mm camshafts or their 10.5mm euro+?
Also piper cams are available
and Kent cams.(didn't find any suitable cams)

and Cat cams.

Alfaholics have their own design as well but they don't give any information on their website (except price).


Do they any of these work on a stock spica and if so what kind of increase, compared to what I have now, would I get?

I know C&B have a few options as well but many complain about their design being old.


I anybody has tried any of these I would really like to hear your thought.
I also know that Richard Jemison here on the board make good cams but no info on price or availability.

Thanks
/Jens
 

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I suggest that you contact Richard Jemison - Alfar7. I have his cams in my road motor that makes lots of torque and at least 170 HP at 6200 rpm.
 

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Cams

I run a pair of mystery cams with the marking "11-1/2" and 10.4 Borgos with a Sperry head on my Spica injected Alfetta ChumpCar. I suspect they are the 11.1mm cams offered by the big retailer as that is what the lift measures. Duration is similar. We have been successful in tweaking the stock Spica pump to deliver enough fuel to be workable but we are right on the ragged edge. We have not yet dyno'd the car in this configuration but I can attest that it pulls like a freight train from 2-6k (our redline).

The ideal answer would be a pair of Richard's cams with a an Ingram modified pump but our budget won't permit that at this time.
 

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Richard Jemison
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Cams

I run a pair of mystery cams with the marking "11-1/2" and 10.4 Borgos with a Sperry head on my Spica injected Alfetta ChumpCar. I suspect they are the 11.1mm cams offered by the big retailer as that is what the lift measures. Duration is similar. We have been successful in tweaking the stock Spica pump to deliver enough fuel to be workable but we are right on the ragged edge. We have not yet dyno'd the car in this configuration but I can attest that it pulls like a freight train from 2-6k (our redline).
Fuel capacities on ALL Spica pumps is limited even with modified versions. To reduce fuel consumption from waste out the exhaust due to the excessive overlap on those cams open the LCs a few degrees. Start with 104/106 and test.
Another (cheapskate) solution is to call Larry at APE and get a 91-94 exhaust cam from the late motronic engines. Those have less early duration than earlier exh cams and you will not find much loss in power. Using 2 of the 11.5 lift aftermarket cams are over exhausting the engine. If the exhaust ports and header inlets are black that`s a clue to do something less radical on the exh side, as your fuel wasted is still burning as it`s leaving. (poor exhaust valve timing events). That is why correctly designed exh cams have much less early opening durations and faster ramp rates (& more duration above .200 lift) to control the power stroke.
 

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Discussion Starter #5
Thanks for your replies. So it is apparently possible to run something in the lines of a 11mm intake cam with stock spica.

Richard what would your suggestion be? Including your own cams. (of course I understand that you preferre your own work, otherwise you would be doing it)
Still.. perhaps you could give an objective view on this.
Price is of course also a factor here. This is not a race car, I can't justify the more then double price of the cat cams compared to centerline if the difference is just a couple of HP.

Richard, did you look at the complete profile of the cat cams? They are provided in the link.

Thanks again.

/J
 

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71 Berlina 74 GTV 17 Giulia Q4
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I use Wes Ingram's 12mm lift on the intake Centerline 11mm cam on the exhaust on one motor and one of Richard's intake and a Centerline cam on another with great results. A few more mods though. In addition to the aforementioned I would also contact Wes Ingram, no one knows SPICA better and he is very helpful.
 

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Last time I talked to Wes, he did not recommend anything over 10.2 mm cams on a stock Spica system (Euro cam is 10.1). His 10.2 mm cam is called the A2 cam. I installed these when I rebuilt the motor and kept the Spica stock. It was a mild performance bump and was a little happier in the higher rpms.

Beyond that, he will rebuild the pump to the cams you pick. I later picked his 10.9 mm cam for the intake and left the 10.2 on the exhaust. I sent him the pump and he rebuilt it to those cams. When my mechanic changed the cam and the pump and tuned it all up, he sent me this nice email which I kept:

the car is running like a scared rabbit when you dip the throttle. ready to go.
 

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71 Berlina 74 GTV 17 Giulia Q4
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There ya go! :)
 

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Richard Jemison
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CatCam profile

Richard, did you look at the complete profile of the cat cams? They are provided in the link.
As I have repeated there is no good data there to compare cams comming from Euro cam builders..
They quote overlap at 1mm (.040) in data and at .050 (1.2mmon the "graph" ?? Actually overlap should be at lash setting (Valve opening) based on Lobe centers. When you look at overlap at lash setting you see the result of the old cam lobe`s large overlap.

What is duration during "open valve" lifts so you can see what they are selling you?
 

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Richard Jemison
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Cams

Last time I talked to Wes, he did not recommend anything over 10.2 mm cams on a stock Spica system (Euro cam is 10.1). His 10.2 mm cam is called the A2 cam. I installed these when I rebuilt the motor and kept the Spica stock. It was a mild performance bump and was a little happier in the higher rpms.
Lift says nothing about the cams capacity to make more power, where it makes power or it`s drivability. Neither will base #s given by other builders reflect on how they alter fuel demands.

I have a PDF file with full profiles of my cams, all Alfa stock cams and many competitor cams that have been tested and profiled on the CamDoctor.

Cam pairings, both intake and exhaust are suggested based on degree of engine preparation and how it is going to be used. No fixed pairings that should "fit everything".
Typically any pair of 4 cyl Nord cams regardless of the profiles they are built with are $500.00 + $40.00 core charge and shipping. V6 12V cams are typically 950.00 plus charge for the correct cores based on application and shipping cost. Regardless of profiles for intake and exh or lobe center repositioning.

Have a question email is how to get info. Not a PM as the BB rearranges PDF files..
[email protected]
 

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Discussion Starter #11
Thanks for everybody's input on the matter.

I am a bit surprised that no I cannot find more owner testimonies on the centerline cams. I thought they they were a big distributor in the US.
I read now that gigem75 (thanks btw) uses these with good results.

Richard, I mailed you just now concerning this.

regards
/Jens
 

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Fuel capacities on ALL Spica pumps is limited even with modified versions. To reduce fuel consumption from waste out the exhaust due to the excessive overlap on those cams open the LCs a few degrees. Start with 104/106 and test.
Another (cheapskate) solution is to call Larry at APE and get a 91-94 exhaust cam from the late motronic engines. Those have less early duration than earlier exh cams and you will not find much loss in power. Using 2 of the 11.5 lift aftermarket cams are over exhausting the engine. If the exhaust ports and header inlets are black that`s a clue to do something less radical on the exh side, as your fuel wasted is still burning as it`s leaving. (poor exhaust valve timing events). That is why correctly designed exh cams have much less early opening durations and faster ramp rates (& more duration above .200 lift) to control the power stroke.
Richard- I am prepping the car for our first race this season. I am planning on following your advice for cam timing. I have determined that our current timing is 96 intake, and 102 exh (using paper templates, is there a better way?). The exhaust ports do exhibit black sooty residue. I wanted to clarify the numbers you mentioned above, do you mean 104 intake and 106 exhaust, or are you suggesting start the exhaust from 104- 106 and test? We have a dyno session scheduled next week and I don't want to waste time by being dumb.
 

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Richard- I am prepping the car for our first race this season. I am planning on following your advice for cam timing. I have determined that our current timing is 96 intake, and 102 exh (using paper templates, is there a better way?). The exhaust ports do exhibit black sooty residue. I wanted to clarify the numbers you mentioned above, do you mean 104 intake and 106 exhaust, or are you suggesting start the exhaust from 104- 106 and test? We have a dyno session scheduled next week and I don't want to waste time by being dumb.
I am currently monitoring the effect of exhaust cam timing on AFR with my 2L Weber motor. This is what I have so far and I will happily share detail with you if it might be useful.
I was running a RJR785 ex cam - 11.7 lift, first with a RJR136 (12.3) intake and more recently a RJR575 (12.8) lift. It was timed at 104. Last week I installed a RJR1291 ex cam (12.1). It has a bigger lobe - more duration at mid and high lift but with less duration at very low lift. With the same timing the whole AFR curve was shifted rich with more shift at mid range (3000 - 5000 rpm). It was then too rich and the car seemd to be a bit slower. I moved the LC to 105.5 today and it lifted the AFR in the mid range and had no effect at 6000 and up. The car seemed a bit faster. I have now moved the LC to 107 and I will repeat the test tomorrow.
 

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Richard Jemison
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Cam timing

Richard- I am prepping the car for our first race this season. I am planning on following your advice for cam timing. I have determined that our current timing is 96 intake, and 102 exh (using paper templates, is there a better way?). The exhaust ports do exhibit black sooty residue. I wanted to clarify the numbers you mentioned above, do you mean 104 intake and 106 exhaust, or are you suggesting start the exhaust from 104- 106 and test? We have a dyno session scheduled next week and I don't want to waste time by being dumb.
How did it get set to 96 LC on the intake?
I`m surprised it runs and hasn`t bent a valve.
Set the intake to 104 and exh to 106.
Yes you are pretty well stuck with using a template as using a degree wheel is about impossible with the motor installed.
What cams are you using? Nothing should be set at 96 LC!
 

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The cams are the 11.5s mentioned above, of unknown origin. I had the same reaction you did when I checked them today. According to my records the were set to 102/102 when I assembled the motor. My crank timing pointer was checked to be spot on at assembly. I will double check my double check of my markings on the bearing caps tomorrow.
 

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Richard Jemison
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Cams

The cams are the 11.5s mentioned above, of unknown origin. I had the same reaction you did when I checked them today. According to my records the were set to 102/102 when I assembled the motor. My crank timing pointer was checked to be spot on at assembly. I will double check my double check of my markings on the bearing caps tomorrow.
If I were you I would set them at 104/106 to get better torque from a wider LSA.
 

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Coming from a different automotive background, I find it odd that Alfa cams seem to be just identified by their ultimate lift.

So many other things are important. Is this just a result of the way they are advertised?
 

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71 Berlina 74 GTV 17 Giulia Q4
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Richard brought up an interesting point. If the ex ports and manifold are black and it's pushing unburned fuel out the exhaust wouldn't that throw off any afr ratio readings and would one be better off running a nearer stock ex cam and keep all that fuel in the cc to be burned?
 

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Richard Jemison
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issues

Richard brought up an interesting point. If the ex ports and manifold are black and it's pushing unburned fuel out the exhaust wouldn't that throw off any afr ratio readings and would one be better off running a nearer stock ex cam and keep all that fuel in the cc to be burned?
Yes the reason exhaust cams should have a very fast opening rate and much less early duration is to reduce the overlap that causes it. Thus the retarded LC on his exh cam to reduce the overlap.

However if you look at the profiles of stock cams at .020 lift (which is lash setting and the point the valve starts to open) most are in the 284 degree area. That would be good, except they have no duration to clear the exhaust created by a decent intake cam.
Intake cams and exhaust cams are (should be) totally different lobes by design. Using the same on both sides isn`t going to maximize power or efficiency. Just be cheap to build..
 
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