rod query
Turbo Mini Forums

In my neverending web searches for stuff I cant actually afford, or even need yet....

I posted a while ago, that I was thinking about a longer rod option, with custom piston....

I measure a stock turbo rod at

main width 26.14mm 1.028"

main journal diam 48.25mm 1.900"

Pin 20.67mm 0.814"

length 5.75" stock 146.05mm ( not measured )

I seen these Evo rods on ebay ( Eagle brand, which Im happy enough to use, and have used in a few Subarus )
Dimensions arent exactly the same, but Im guessing with some minor machining, could be useable ? with custom pistons of course

clickyusa
H-Beam Rod Specs
5.900 Rod Length Apprx. Gram Weight 575
1.771" Crank Pin .826" Piston pin
B.E Width 1.117" Bushed Fit Pins - Full Floating

Or UK seller, dims are slightly different, but diff year Evo.
clickyebayuk
4340 Forged Steel

Journal = 48mm
Width = 26.4mm
Pin = 22mm
Length = 150mm

Weight - 533grms each
ARP 3/8" 2000 Bolts Tested to 190000psi
Dowelled Cap for Precision Fit
Precision Sized
Balanced to within 1 gram
Crack tested and Shot peened

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

How much?

Scratch that, just found the links, lol

Edited by Sprocket on 23rd Feb, 2007.

I'll keep it in mind and research it for next years build

One thing I have thought of is, how would we over come the offset of the little end that the A series rod has

Oh and another, im suspecting the big end overall width may be too big to pass down the bore. Not so big an issue as you could assemble the pistons onto the rods through the engine

Good find, im interested

Edited by Sprocket on 23rd Feb, 2007.

There is an offset to both big and little ends of A series rods.
I have a set of steel rods I bought from EBAY which will be usable but not perfect in terms of offset. Fastcarl machined some spacers to rectify the big end offset and width problem but it still leaves the problem?? of the small end with no offset. this will mean the rod is running offset on the piston pin by (from memory) around 2.0mm.
Do you think this may be a problem?
will post some pics in the morning.
Regards
Dave

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

I *think* someone is working on Alloy rods for production at the moment...

I reckon these guys just need convincing that if they manufacture them - we will buy them!

Longer rods will mean the JE piston (which is way too short, but cost-effective) will be a realistic proposition again?

Or, Dave

Were I'm concerned, shorter stroke

JE pistons will do you a piston to your own specs. From what i gathered at the autosport show when i enquired they are supplied with rings, any number of rings, any deck height etc.

All for only $150 a piston, which means you can use proper a series steel rods.

LOL rods can handle 600bhp/9000rpm would be intresting, what else would break first

Here are a few pics of my Ebay rods.
As you can see from the pics they are symmetrical and at first glance they appear to be a non starter.
What I plan to do is to use an ally spacer on one side of the big end to give the required offset at the crank end. These will be fixed to the rod and cap with 3 off 2mm Csk set screws.
The little end should be OK with just one side machined down by 1mm.
It will mean that the rod shank is running offset to the piston centre line by 1.5 - 2.0mm (Do you think this may be a problem)
The rods are bushed and the pistons I am using are Omegas which have large flats on either side. will PTFE buttons be OK to locate the pins or should I put circlip grooves in the piston?
Would a press fit pin be OK if the bush is left in place as an alternative?
How much side clearance between rod little end and piston boss is advisable to allow for crank flex?
I think any input on these questions could prove very useful if alternative rods are to be found and used.
These rods are german made and were bought from ebay for £30 +p&p. No sizes were given and as i work on a few different motors I took a flyer and bought them.
They turned out to be spot on for length, 004" under on big end dia & 012" under on little end dia. Lucky or what!
I contacted the manufacturer to find out there original application but unfortunatly they turned out to be arrogant and totally un cooperative.
I did a little research at the time and the closest match came from a BMW car engine.(cant remember which).
Regards
Dave

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9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Stevie,
I cant see that there is any significant side load on the spacer and it will be swilling in oil which should help.
Time will tell
Regards
Dave

Why bother ? Buy some 970S rods, they are about 1/8" longer and have smaller big end than A+. You can either buy a matching EN40B crank with S big end size or machine an A+ crank to S big end size (offset if you wish more stroke).

Not that this option would be cheap ...

BTW, is the Rover rod somehow questionable in terms of reliability ? Especially with turbo engines that rarely are revved high enough to need high end rods ?

I never had rod problems on any of my mini engines...

Good point....maybe std rods are more than capable of handling any power we throw at them ?

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

so it would seem,

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

It is true that a set of Carrillos, Arrows or whatever brand look really high tech compared to std rods. But when fitted no one sees inside the block.

A bit of OT: I remember a local character who supposedly had a n/a stroker engine, around 1460-1480 cc, that easily ran to 9000 rpm, had hp figure around 130 hp and a single Weber or Dellorto 40 fitted. The only detail that could be verified was the carb. The car was later sold to a new owner but mysteriously the engine blew up beyond salvage before the deal was finalized. Any thoughts ???

Back to the thread; given the fact that factory rods are really sturdy items provided they are prepped and fitted with high quality fasteners I don´t personally see any point in wasting a load of money to " unnecessary" details. If we are talking about high revving race engines then uprated rods may be a necessity. IIRC, with turbos the major loads are compressional loads.

standard rods are fine, but if your after the best Arrow do some nice steel ones and for ultimate they can do titanium.

i saw some of the titanium rods a good few years ago now, and they were £800 then!!! and that was each!!!!!