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Discussion Starter #1
I've been looking for this info for some time now, with little luck..

Does anyone have specifications for the 90-94 Motronic Spider Intake cams? I've read that they are 11mm lift, but I have no other data on open/close timing.
 

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although I am not sure of the source of the following information, I actually have it written down in one of my files. So either I got the info from here, or I just made it up;).....but somehow doubt i'm smart enough to make up such things!

anyway be it right or be it wrong, these were my notes for the S4 motronic VVT inlet cam:

valve clearance - 0.015-0.018" (0.381-0.4572mm)
nominal lift - 11mm
duration - 299*12'
timing - opens 24*44' to 17*44'. closes 94*28' to 101*28'.
lobe center - 125*30'


I'm sure RJ, if he's looking in, will be able to comment.
 

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Discussion Starter #6
You could drive over to Prescott Valley and we could look at the cam in my spider. :)
I might have to take you up on that! It's starting to heat up down here, so time to take some drives up north!
 

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Discussion Starter #7
That is very useful!!

So this combination, with a Euro exhaust, gives decent overlap with a good lobe angle...

Obviously there is more to it than that--I'm just trying to decipher what my old mechanic recommended to determine if I should do something different or just go with it. The car pulls hard from low, but runs out of steam a bit at the high end. I'm wondering if it just needs more fuel from the SPICA system.


although I am not sure of the source of the following information, I actually have it written down in one of my files. So either I got the info from here, or I just made it up;).....but somehow doubt i'm smart enough to make up such things!

anyway be it right or be it wrong, these were my notes for the S4 motronic VVT inlet cam:

valve clearance - 0.015-0.018" (0.381-0.4572mm)
nominal lift - 11mm
duration - 299*12'
timing - opens 24*44' to 17*44'. closes 94*28' to 101*28'.
lobe center - 125*30'


I'm sure RJ, if he's looking in, will be able to comment.
 

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Richard Jemison
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Cam from Motronic Spider

Obviously there is more to it than that--I'm just trying to decipher what my old mechanic recommended to determine if I should do something different or just go with it. The car pulls hard from low, but runs out of steam a bit at the high end. I'm wondering if it just needs more fuel from the SPICA system.
As well you need to consider the limitations of the Spica for fueling as part of your issue. The 10.5 cam mentioned below, with a Motronic exh might be your best bet. (see below I have both $300.00 )


It is more cam than others, So much more they won`t fit:frown2:

All of the Alfa cams from the 101 series up, including the Motronic exh cam, have base circles of 1.080-1,085. The Motronic INTAKE cam has a base circle of 1.165 (2mm larger!). With any motor other than the Motronic Bosch head your valves will be unable to close. (Nor will the cam rotate due to interference with the cam follower bore )

I have the full profile but the BB system F`s up PDF files so below are the important lobe specs:
.020 286 LC 118 un-advanced
.050 237
.100 217
.300 134
.350 113
.400 28

If you are looking for 11mm lift cams I have 4 new 11 mm Alfa cams with the 10548-51 lobe design. New on factory castings for sprockets, not VVT(not re-ground or hardwelded etc)
Bought the batch to measure. These are "old profile designs,( ie typical Alfa) Although considered "performance cams', they will not match output of modern 11mm cam lobes.
See my last post at:
http://www.alfabb.com/bb/forums/alfa-romeo-parts-sale-wanted/438449-cb47-group1-camshafts.html
$200.00 each shipped in the USA. I also have a new 10.5mm lift cam with a much faster ramp rate that would be a good exh cam for one of these .
 

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Discussion Starter #9
Thanks for the reply, Richard.

SO rather than be lazy, I pulled the cam cover to see what was under there.

It appears that the head was modified to accept the Motronic cams--see attached pics.

Which means two things: first, these are in fact 11mm lift cams with VVT; and second, standard cams will probably not work in this head anymore :)

Which brings me back to square one....will a HP SPICA from Wes give a little more power on the top end? As I mentioned, it pulls hard low--plenty of torque with this combination. I'm just wondering if a bit more fun can be had above 5k.
 

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Discussion Starter #10
Well, apparently the BB is not posting photos correctly.

The intake cam part # is 116.85 0320001, which I believe is the correct # for the motronic cam. I measured the lobes as best as I could, and the are within the range you stated for that cam, and it appears to have ~11mm lift.




Thanks for the reply, Richard.

SO rather than be lazy, I pulled the cam cover to see what was under there.

It appears that the head was modified to accept the Motronic cams--see attached pics.

Which means two things: first, these are in fact 11mm lift cams with VVT; and second, standard cams will probably not work in this head anymore :)

Which brings me back to square one....will a HP SPICA from Wes give a little more power on the top end? As I mentioned, it pulls hard low--plenty of torque with this combination. I'm just wondering if a bit more fun can be had above 5k.
 

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Richard Jemison
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cam

I doubt this really a Motronic cam. Just notching the cam bores won`t make it fit. What is the measurement side to side? (not nose to heel)
If it`s a Motronic cam it will measure over 1.165" as rge ramp starts before the center of the shaft.

It would require short valves and internal clearance mods to fit at all.

Cams for Spica have to be built to a design that does not have much overlap or the Spica`s capacity to make adequate fuel is wasted.
You are not going to get there with any of the stock Alfa cams as they are just too inefficient.
You should reset LCs to 116 (not 114) int and 106 exhaust. That might help.
 

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I doubt this really a Motronic cam.
the alfa motronic/VVT inlet cam (SPIDER 90, Alfa 75 1,6/1,8) is numbered 6054 9786

not sure where that 116***** inlet cam is from, sounds like a tipo '116' alfa (Alfetta GTV maybe?)
 

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Which brings me back to square one....will a HP SPICA from Wes give a little more power on the top end? As I mentioned, it pulls hard low--plenty of torque with this combination. I'm just wondering if a bit more fun can be had above 5k.
I'm afraid nobody but Wes himself could answer...
At high RPM, it's pretty much the same as common high-lift cams; the VVT was made rather for decent low speed torque and smoother transition (and for emissions purposes, of course). It's supposed to switch at ~1600 RPM and 70% throttle, AFAIK, so most time you accelerate it's on; most time you cruise it's off.
 

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Discussion Starter #15 (Edited)
I measured it with calipers, and it came in at 1.17" (give or take, since it was hard to get the caliper arms in the right spot). You can see visually that the base circle is noticeably larger than the exhaust cam, which is a Euro exhaust. When Stewart Jr had the head off and was porting/smoothing everything out, he must have used shorter valves to re-assemble and make it all fit.

Let's see if the images attach this time...

As far as overlap goes--if my calculations are correct, it looks like the overlap is 64 deg and LSA 110, which is a lot lower overlap and wider LSA than the stock cams. I'll stop now before I reach the limit of my knowledge....

Without using a wideband O2 sensor, I have no way of knowing if I am lean at high rpm, and therefore need an HP pump for more fuel. Which is why I'm tying on a keyboard right now instead of in my garage :)


I doubt this really a Motronic cam. Just notching the cam bores won`t make it fit. What is the measurement side to side? (not nose to heel)
If it`s a Motronic cam it will measure over 1.165" as rge ramp starts before the center of the shaft.

It would require short valves and internal clearance mods to fit at all.

Cams for Spica have to be built to a design that does not have much overlap or the Spica`s capacity to make adequate fuel is wasted.
You are not going to get there with any of the stock Alfa cams as they are just too inefficient.
You should reset LCs to 116 (not 114) int and 106 exhaust. That might help.
 

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Discussion Starter #16
Makes sense now. If I remember right, this came from Europe, so it's the same cam with a different part#.



Yep, late (euro) Alfetta with Motronic. Should measure 41x30mm across the lobe (if not reground). IAP used to sell the reground ones; where have they gone now?

P.S. Here's a PDF manual on Euro engines; look for 017.13 specs: http://www.vintagegarage.ru/files/Petrol engines.pdf
 

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Yep, late (euro) Alfetta with Motronic
it is an odd beast that, I was reading it has Bosch Motronic ML 2.1 with the Bosch 0 261 200 044 ECU and (similar to the l-jet spiders) 2 flywheel sensors Bosch 0 261 210 001

wierd.
 

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Makes sense now. If I remember right, this came from Europe, so it's the same cam with a different part#.
Where is the timing mark on this head? It should be 12.45" degrees to the intake side (to give mininum overlap at idle). I see the head has recessed follower wells, cast like that, not milled, so it's (probably) already a VVT version.
 

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although I am not sure of the source of the following information, I actually have it written down in one of my files. So either I got the info from here, or I just made it up;).....but somehow doubt i'm smart enough to make up such things!

anyway be it right or be it wrong, these were my notes for the S4 motronic VVT inlet cam:

valve clearance - 0.015-0.018" (0.381-0.4572mm)
nominal lift - 11mm
duration - 299*12'
timing - opens 24*44' to 17*44'. closes 94*28' to 101*28'.
lobe center - 125*30'


I'm sure RJ, if he's looking in, will be able to comment.
Im not sure I understand the numbers here. Its a total of 299 degrees?

But when does intake open and close? For instance, the QV/S/SZ cams for the 12v V6 is 33-74 intake timing and 67-30 on exhaust. How would those numbers look on the 2.0 VVT NORD engine?
 
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