Amazon: Race prep a B16 for historic racing

[worksvolvo]

I am building (another) race Amazon - this time for late '50's racing with the B16 engine and front drum brakes. I have previously built a B18 for tarmac rallying (see Youtube 'volvo' & 'targa')
Has anyone had experience with modifying the B16 engine for racing - HS6 carbs?, big valves, head work? crank?, cam specs. The Group Na class of racing allows boring to 1642cc. Any information, advice welcome.

[arcturus]

The B16 is a really good torque-y engine but remember it has only three bearing crankshaft as against b18/b20 five bearing. The guys on the Swedish PV club should be able to help you. Most of them speak good English.
https://www.facebook.com/groups/3100...00258373256324

[Volvorama]

Did a 444KS in 1990 for a Monte Carlo rally historic (pre 1960 supposedly) with Pete Fluitman. Regularity run but we got carried away with the engine. Very powerful but threw a rod after 5000 miles.
Good things we did:
Used a B16 engine from an early 122S
Aldon Automotive distributor based on a BMC A-series unit to match a modified camshaft.
Flywheel modified to fit a B18 clutch.
Other stuff common to the usual engine mods.
It was a very, very hot engine but it was done in a hurry.
Lovely smooth, revvy engines but much more delicate than a B18 and the parts were appallingly expensive and hard to find.
Things we learned:
The original B16B exhaust manifold fries the starter motor as it gets red hot so we had to add heat insulation.
Make manual brake adjusters as the automatic ones were not good (doesn't apply to an Amazon anyway).
Many other things to say if you're interested.....

[worksvolvo]

Thanks for that info Mark. Interested to hear more. 5000 miles not bad but did it get to the finish? I have a motor from an early 122 (one of only eleven cars imported into Melbourne in 1961). I am thinking about forged pistons. Am interested to know best carbs, porting, extractor design, camshaft specs - I see Isky list a cam VV-71. Any info/photos on engine mods appreciated.

[blueosprey90]

Was there any denouement to your build? I would like to find a source for some performance modifications for my very stock '57 PV444 B16B.

Never likely to race it competitively, but I have many opportunities to get it on track.

I probably need to start with taller differential gearing.

[davidw6092]

I looked after a pv rally car with a B16 in it for a couple of seasons.Ran well on twin su,s and a ported head.Eventually broke the crank just behind number one main bearing in Austria on the Liege-Sofia- Liege rally.Replaced it with a B18 for easier availability of parts.Again good insulation over exhaust manifold is well worth looking at.

[blueosprey90]

Thanks David,

Is there any sort of competition or performance tuning manual out there for the B16?

Although I think my differential is my primary limitation at present, I do anticipate that I must make the engine breath better. I'd hate to have to use the string method for porting if someone has already determined the best porting options. http://www.diyporting.com/thread.html

On my MG B type engines, there is a large valve guide boss behind the exhaust valve. Cutting that down properly and installing a larger exhaust valve causes a major improvement.

I could anticipate the crank weakness of the B-16 engine, having broken the crank on my 3 main MGA engine.


https://youtu.be/86U864g4xpQ

[Vintagewrench]

Originally Posted by blueosprey90

On my MG B type engines, there is a large valve guide boss behind the exhaust valve. Cutting that down properly and installing a larger exhaust valve causes a major improvement.

B18 intake valve guides and stems are also restrictive. I machine new guides and use B20 valves with smaller stems, you can view the finished product here:
https://www.volvoforums.org.uk/showp...5&postcount=80

Are you going to the Spring Sprints at Lime Rock? I'm getting the 1800s ready now.

[blueosprey90]

"Are you going to the Spring Sprints at Lime Rock? I'm getting the 1800s ready now."

Not with the Volvo.

I think I've missed only 1 race event in 9 years - much to my wife's annoyance. Wedding or funeral, I'll do my best to get a few laps in on Friday morning and come back for the all comer's race Saturday afternoon.

But I must admit that the pesky Volvo is keeping me off balance. I'm putzing around trying to get that heap back on the road with seat belts while I have an engine to build - well actually three.

I broke my crankshaft in Sept. 2017 (3 main bearing), and although damaged, I'm rebuilding that block with a hybrid, ghost main crankshaft. I think I now have most of the machining done, so I hope to start the test assembly soon (like Christmas eve).

Whether it gets into the car by the Spring Sprints is open to question as I also hope to prepare a new transmission and drive shaft to go with it.

Then I also have a 1622 block with a very high lift camshaft (and domed pistons) that I need to figure out. My guess is that it needs custom rocker arms or at least pedestals for the valve train. There are two well known MGB engine builders who, from the documentation, have their finger prints on the engine with whom I will need to consult.

Finally, I have a 1500 block with a fast street cam. The block is bored out .080! I've been tripping over that one for years. Just bought new pistons and plan to take it all into the machine shop this winter.

But don't worry. You'll be faster than me. I'm on skinny tires and stock suspension.

[Vintagewrench]

Originally Posted by blueosprey90

I broke my crankshaft in Sept. 2017 (3 main bearing), and although damaged, I'm rebuilding that block with a hybrid, ghost main crankshaft.

Unfortunately, most three main bearing crankshafts after a long duty cycle are subject to breaking in due time. Have replaced a number of them here in the machine shop before breaking with new ones, or after an original breaks.

Care to tell us more about the hybrid ghost crankshaft?