I'm putting together a basic small block engine to use as a run around.
I have a 175 barrel (not sure if it is a 175 or a bored out 150) going to get a 175 2 ring piston off ebay and use a 30mm manifold i have in the shed.
Questions are;
Can I use the port timings in Dave Websters book for the 150 tune? exhaust 170 transfer 120 inlet160
Because of the poor rings going to open exhaust port to 62% of bore 39mm, this ok?
What width and shape to use for the inlet port?
What bore clearence to run?
Is it worth cross hatching the piston skirt inline with barrel studs to aid lubrication?
Is it still ok to get squish as close to 1mm as possible?
Going to run a clubman/ indian big bore/ fresco
Thoughts and tips please, Dave
Basic tune to a cast iron 175
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Can I use the port timings in Dave Websters book for the 150 tune? exhaust 170 transfer 120 inlet160
Don't see why not!
Because of the poor rings going to open exhaust port to 62% of bore 39mm, this ok?
Yes, as you say it's only a run around.
What width and shape to use for the inlet port?
Just match it up to the manifold for good flow, it's only a run around
What bore clearence to run?
3-4 Thou max
Is it worth cross hatching the piston skirt inline with barrel studs to aid lubrication?
Wouldn't bother myself
Is it still ok to get squish as close to 1mm as possible?
1.2-1.5 would be safer
Going to run a clubman/ indian big bore/ fresco
I'd go for the Clubman. I have had a go on a cast cylinder at opening up the transfers (with a Dremel) (and only from the bottom up, not inside the cylinder)and then matching the casings
Don't see why not!
Because of the poor rings going to open exhaust port to 62% of bore 39mm, this ok?
Yes, as you say it's only a run around.
What width and shape to use for the inlet port?
Just match it up to the manifold for good flow, it's only a run around
What bore clearence to run?
3-4 Thou max
Is it worth cross hatching the piston skirt inline with barrel studs to aid lubrication?
Wouldn't bother myself
Is it still ok to get squish as close to 1mm as possible?
1.2-1.5 would be safer
Going to run a clubman/ indian big bore/ fresco
I'd go for the Clubman. I have had a go on a cast cylinder at opening up the transfers (with a Dremel) (and only from the bottom up, not inside the cylinder)and then matching the casings
Compact Toolbox Flywheel Holder
Try and use a genuine 175 head if you can, as it will make getting the compression somewhere near usable. Some 150 heads that are skimmed & reprofiled to 175 are so high that they can cause engines to run hot.
Personally I'd cut the inlet timing to 150° otherwise it will spit back a lot of fuel at low revs, and at £1.36 a litre you need to save as much as possible. You also want to keep as much low down torque as possible on a 175, remember it s lot easier to take some more iron off or cut the piston skirt than it is to put it back on.
Good info also here:
http://sites.google.com/site/drunkmunke ... nceporting
Good info also here:
http://sites.google.com/site/drunkmunke ... nceporting
Best Regards
Chris
Chris
If you don`t fancy doing the work yourself,then give mick Abbey a call.A fantastic fella and a sh!t hot tuner. I have a 150cc barrell that he has is hands on and i`ve done over 70mph(gps) with it.I also was running a cheapo ebay piston which did me proud for over 3000 miles.
Was due for another dyno run last friday but on way up to ripon(from norfolk) the head came loose and piston siezed its rings in groove. F`ing gutted.
Anyway Mick abbey is the man for the job . 07802896103.
Was due for another dyno run last friday but on way up to ripon(from norfolk) the head came loose and piston siezed its rings in groove. F`ing gutted.
Anyway Mick abbey is the man for the job . 07802896103.
Aussie - if its an original tv 175 barrel, try to use a crank with a 115 / 116mm rod. Overbored to 64mm, you can then you can use the shorter crown height TS 185 piston (£40 piston kit brand new c/w quality rings) and have all the in built torque benefits / adaptability of port timings ,of the longer rod combo. just a thought
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Thanks for all your comments.
How can I identify what barrel I have? Cant find any casting marks on it but the transfers on the base gasket face do look quite small so dont think it is a TV175 barrel
How can I identify what barrel I have? Cant find any casting marks on it but the transfers on the base gasket face do look quite small so dont think it is a TV175 barrel