B20e cam profile
 

Hi, Rebuilding B20e engine for 1800es. Cam needs replacing and I believe the original profile is a D. Is there any reason to consider a K profile or is it best to remain stock? Usage when restored will mainly be regular road use so I'm after good easy response in traffic.
Thanks in advance.

Quite a bit of information here =>

https://www.volvoforums.org.uk/showthread.php?t=19989

And here:

http://www.1800philes.com/ianr/_superlist_grinds.html

Thank you both for responding. It is appreciated.
I have seen both of those items and the one seems to be addressing possibilities on carbs more than injection. The second item is very in depth technically but I can't work out if the info I am after is in there.
I intend sticking with ths injection system so any feedback on the differences in performance of the 2 profiles on injection would be greatly appreciated.
If no advice to the contrary I will stick with the factory D profile.

I'm not going to pretend I understand all the complexities of the second technical link: But the only difference I see between the Volvo D and K cams in that link is a slight change in timing - the numbers look pretty similar to me.

If I were you I'd go for the cheaper option and see how you get on. The slight increase in displacement of the B20 is going to be a bit of a boost - you're also probably going to have a few irritating issues that could soak up the cash which is bound to happen when fitting a different engine so I'd save the dosh for that...

...you can always modify things later on

EDIT: I posted this here by accident, but not sure how to delete.


harpgirl's thread on the 1800 B20e cam profile has been truly enlightening. :regular_smile:

Although I'm wanting to soup up my B-16B engine, I haven' found any sort of special tuning or competition preparation manual to guide me. And when I see advice about the B-18 or B-20 engines, I see somewhat vague suggestions of different lettered camshafts. In one of the linked threads, this was a complete summary posted by ClassicSwede

"A cam is for single carb engines
B cam twin carb engines
C cam P1800 and 123 GT
D fuel injection cam
K cam fast road B18 or mild street B20
R cam Very fast road B18 or fast road B20
S & T full race B18 Very fast road B20
U & V full race B20

I hope that explains all the cam profiles"


Well, of course, it doesn't explain anything about the cam profiles, e.g. duration, lift, lobe separation angles and the like.

But the link by Ian R., also linked in that thread, has outstanding camshaft information.

http://www.1800philes.com/ianr/_superlist_grinds.html

So, for example, I can now see that a Volvo K cam has 222 degrees of duration at 0.50" lift, lobe separation of 111 degrees and a max lift of .420" at standard rocker arm ratios. (This is useful because, although I am a mere rank amateur engine builder, I can still relate the information to the camshafts in my primary and spare MGA engines.)

So even if the B-20 camshaft information doesn't translate directly to the B-16B engine, Ian R's data gives me a huge jumpstart on the data that I'll need to start developing to build up my engine.

That's a couple years away most likely. In the meanwhile, I'll keep looking to develop the information for the B-16B and in the meanwhile try to get that lump humming like a well oiled sewing machine.

D cam goes with the D-Jet FI and the K cam goes with the K-Jet FI. Not much between them but the K is designed to run a bit quieter and also help with emissions. With the K cam, the starting and closing ramps on the cam are a bit less abrupt than the D. This is also a bit kinder on the rest of the valve train.

With this in mind and the vehicle retaining its D-jet injection would you say just stay stock and use a D?

Sticking with the D is fine. You must use new cam followers with it. Run the engine for 20 - 30 minutes at 2000rpm at the first startup to bed in the cam and followers. Heavily coat the cam lobes and cam follower faces with cam lube when fitting. Change oil after this first run and then run in the whole engine for about 500 miles before changing the oil again. New filters too. You can retorque the head bolts after the initial running. Loosen bolts a fraction and then re-torque. Rocker gear will have to come off to do this unless you have a crows foot spanner to do the hidden central bolt. With that, you have to compensate for the extra length so rockers off is easier. Reset valve gaps after final torquing.

My .02¢

I recently put together a B18 bored for B20 pistons, with B20 head @ 9.5 CR, and lightened flywheel to mate with a M41/J-OD to go into my '62 sedan with it's original 4:10 rear.

As I specifically wanted to be able to easily power the .80 OD between 1.5-3.5K rpms/50-80mph, I wanted a cam with as much "grunt" in that range as possible i.e. torque...

Based on my knowledge over many years, the K cam (developed in response to increasing avoirdupois across 140/1800 line) will produce more torque in the 1500-4000 range than any other factory cam, with a slight drop-off of >4K rpm hp compared to the D. That's why I chose the K.

No reason you won't be happy with either.

For these cars I like more torque; there are better cars to enjoy more horsepower.