h beam rods for small bore
Turbo Mini Forums

Hi
I'm currently building my 998 turbo engine up and im busy gathering parts and i was considering upgrading the standard conrods after having one fail in a previous engine not totally sure why? Anyway i was interested in the conrods produced by specialist components for the 1275 engines after seeing some really nice parts and having bought some in the past. So i emailed them asking about the possibility of producing a similar set for small bore engines, the reply i got from simon was that there were no official plans to produce them but they would consider a batch if there were at least three set ordered. the price as quoted was to be around the £350 plus vat with a lead time of 4 weeks. so my question is, would anyone be interested in these??

You really only need better rods if you are going to rev the tits off it. We run standard rods in the hillclimber and that has plenty or bananas, never had a failure. I know it is not a high miler, but it is very stressed.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

ive read in numerous places that in theory con rods are less stressing in a forced induction engine than an NA engine, im just going to use arp's in my build as an insurance measure for the gearbox

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Not actually less joey. The maximum stress (at tdc on the exhaust stroke) is slightly more.

The main increase in stress with a turbo motor is mid stroke, but this dosen't generally exceed the maximum seen at other points in the cycle. So it's an increase that you don't need to worry too much about.

Better to spend the money on ARPs and maybe modding the standard A+ item.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

Agree with the above.

Probably better off spending money on modifying the standard item.

These are my 998 rods for my 9000rpm K100 engine:



Cost about half the above price.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

If you are dead set on H section rods, I remember John Kimmins posting that SC would shortly be producing H setion S rods,

you could use these and machine them to fit, cant remeber the details of the mods, but IIRC you remove the offset, I'm sure there is info in the Big yellow bible.

Small bore ones would be a bit more tricky to make due to the angled cap i would have thought.

then again they get the S ones to fit so maybe you dont need it

Edited by slater on 13th Nov, 2008.

Are all these fancy rods really needed, or are they just worth bar room bragging points?

Seeing as the DON revs to 9200rpm on a modified standard rod I'd suggest they are not needed.

how much boost tom?

Paul, are those shot-peened?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

To ask an obvious question (but the stupid ones are the ones you don't ask...), what exactly IS shot peening, and why is it done ?

It's one of those phrases that gets bandied about a lot in the comics.

Metric is for people who can't do fractions.

Its basicly like sand blasting only with shot that hammers the surface of the rod and forms a work hardened skin that stops cracks starting and closes up any stress raisers etc.

http://en.wikipedia.org/wiki/Shot_peening

Thanks chaps - all is now clear.

Metric is for people who can't do fractions.

managed to dodge my question Tom!! haha