seeking advice on 402 engine upgrades

[chas]

4 advice

Many mahalos to you all for your sage advice on the care and feeding of my still dormant 402.

[chiefj48]

i had my 440 out today, and it sure runs sweet!!

[JURIS R.]

Peter,

I have been reading your posts very carefully as I am based in Latvia, a Baltic state in Europe and with regard to restoration of my 1929 Indian 402 I am in complete isolation, like living on an island. However I do have a well equipped workshop (www.ramoto.lv) which is busy with modern cylinder head work and block rebores, line boring, etc., so basically I need some know-how and a few spares to rebuild my cherished machines...

My 1929 402 rolling chassis was found locally and the engine/transmission bottom half was bought unseen in the USA a while back following a 10-year search. As it turned out the rods that came with the egine are a 1936-1937 type and not suitable for conversion to B-850 alutin I am going to use. They are perfect rods, but the distance between the studs is much narrower than in the 1929-1935 type rods -- they had been babbited direct without using a babbit lined bronze bearing. I have read recommendations about using conrods of the Indian Vertical twin 243 or Warrior in the older type 402 engine and noticed that you have mentioned the same vertical twin rods. I have only seen these vertical twins in photographs, never in flesh. Could you please advise where a set of 4 such rods could be obtained? Do they have the same dimensions -- between centres of small end and bigend as on the 402? I.e. if comp. height remains the same? What material are they made of and what needs to be done to convert them? Am I right in assuming that comp. height on early Indian fours at 27.5 mm is different from later Indian fours at 38.1 mm? Would you recommend fitting forged full skirt pistons with modern rings to a 1929 Indian 4 engine? Would 0.06" running clearance for forged piston be adequate enough?
I have done extensive repair welding of the crankcases and will soon be doing lineboring of the mainbearing seats. I am going to use NOS mainbearings which are babbit lined bronze. My 5-bearing crankshaft has been built up with welding and reground to standard size, 4 additional oil holes drilled and then the crankshaft has been nitrided to improve its hardness to HRC 55.
I will appreciate any advice you can kindly share.
With best wishes,

Juris R. in Latvia

1926 Indian Prince
1926 Indian Chief
1929 Indian 4
1928 Henderson De Luxe
1937 Harley-Davidson 61E