B18/B20 camshaft experiences and options.

Hi, I had a couple of cams made in Melbourne to a so called "towing spec" for the b20 and have been very happy. A similar cam to the very popular IPD street cam. They give a much lower down and broader power band, and make a very nice tactile engine. Finding an IPD cam is the cheaper option, but I can find the cam specs I had made. I built tmy engine to remain bullet proof, but with full dynamic balancing, lightened flywheel and lifters, lightened steel timing gear (r sport style) and slightly modified and polished head. I was wanting a nice all rounder car, 100 mph top was still plenty, and I did not want an engine that would be unreliable. I wanted to use standard SU carbs. At a dyno day it had more power at the wheels than modern 240's and an injected 1800ES that had allot spent on it. I think that if I had different carburetors and a higher compression the cam would continue to perform well. IPD cams of this type were very popular on modified engines with success, and had a reputation for performance without being peaky/a pain to drive day to day. I also like the standard D cam in an injected engine, but power comes on too late in a carburetor car. Every engine with a D cam has had a worn cam so far that I have encountered, but possibly modern oil and being sure the lifters are not sticking at all will solve this problem. With a modified setup like you describe, whatever you choose is going to end out a bit of a case of give it a try. It is tricky, but it is possible to change the cam later without removing the head by using using high powered magnets on a stick to lift the followers if they are not jammed.

From memory I think it was a mighty 66 kw, but standard late 80's 240's were delivering around 45 kw I think. There is a write up in a volvo club of Victoria magazine a few years back on their dyno day.

My paperwork is in Melbourne, so I don't have the specs to hand. It will be a couple of weeks.

Yes it was at Swinburn, some years back. I think that 140 and 240 engines do very well with some modest work on reassembley - a little goes a fairly long way. Couple of pic from this engine below. The most complicated bit was lightening the timing gear to r-sport style and keeping it balanced, but I think the overall reduction in rotational mass made a decent difference to the engine being much smoother than a standard b20<img src="https://ozvolvo.org/uploads/FileUpload/79/3d92c2a920689936c951229c2deeee.jpg" /><img src="https://ozvolvo.org/uploads/FileUpload/88/d2f9707a5ff37ee5c1530a8ab35883.jpg" /><img src="https://ozvolvo.org/uploads/FileUpload/cd/56de3f2edfc0c697f3a3c7ae02cdff.jpg" />

Vee_Que;73060 wroteDid you do much work on the exhaust side?
Is the down low torque worth the loss up high?

Just a word of caution on Tighe Cams, his rebuild cams are not very successful and I found as others have that wear is very poor for dollars spent. For my last engine build(1.8) I went with Clive Cams regrind and after speaking with Clive we picked a grind that I would be happy with. The motor was balanced, lightened flywheel, 11 to 1 pistons , big $ rods oil pump etc. Head was done by me with over 100 hrs in welding and porting, bigger valves etc. Cams were dialed in and straight off the bat 145RWHP and when dynoed 185 but pulled back to 165 for reliability. The biggest thing I've found over the years if you want good torque is good sensible cam and big compression and work out what quench you can achieve with your type of engine. On the Mazda my pistons were over 1mm proud on the block, the car would still pull from 1500rpm in top all the way to 7000rpm, so it was a good road car and a bloody quick race car.

Clive is a pretty decent bloke who will work with you but will also tell you if your wrong, he has the knowledge to help you with any machine work theories you may have.

My 2c worth.

Our standard rebuild in the 80's for 8 bolt cranks was std B21 Volvo Pistons k cam with a 10.5 -1 injected cylinder head. Chevy grey white valve springs and upgraded push rods.This worked well on re jetted SU's. We concentrated on porting the exhaust port and just cleaned up the inlets. We un shrouded the valves in the combustion chamber.
Back then Holden Pistons were cheap and prone to failure hence genuine Volvo.
For big horse power race engines on Webers
we used a high lift Kent cam that helped wth the bad exhaust.
You can do a lot better than R sport headers.
If you are going Webers get 48's

Vee_Que;73156 wrote But i will look into Clive. Though its also about cost effectiveness.

That and the ability to talk in plain ol' english without the crapola is the reason I went with Clive. I doubt you have priced a cam from Tighe, if you do make sure you have Ventalin handy, as his prices these days certainly took away my breath!!

Sorry, I didn't know you already had all the parts. The 45's will work well, their is a significant power gain in the 48 when you go bigger in the cam.the factory long runner inlet manifolds worked much better than the short Links manifolds too. Terry Parker in the USA makes replicas.
We only used the K cam on cars with SU's . I think to get a Benifit from the Webers you need to go bigger in the cam. I used a Kent cam with big lift. Originally designed for a Push rod ford.
The Holden piston failures were Gudgeon pin, and the top coming off,separating from the ring groove. This was 30 Yeats ago! Holden Pistons were used because they were so much cheaper than Mahle or Volvo, but back then couldn't handle the Rpm, not many red motors can spin to 8000.
I had a factory set of r sport headers that we played with the length of the secondary pipes.
We kept getting a weird resonance that would crack inlet manifolds and heat shields. I stopped the cracking by supporting the inlet manifold with a brace to the engine mount.
A good 4 into 1 will work better, The Webers give great mid range torque, especially if you build an over 2.0 engine.
I might still have a small alloy front pulley left over if your interested.

To answer your question on the K cam over the D cam, the K revved sweeter for longer.

This is interesting.

Alex Clive cams is who did my cam.

The bracing is interesting, as I had the rear manifold bolts rattle loose resulting is a blown out gasket and severe vac leak. (Since then I've used dome lock nuts with spring washers and high temp lock tight.) going to be a pain in the ass when I want to remove them. But they are on there tight.

Absolutely!the extra torque is awesome. Put some longer runners on the that manifold too.