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1632499907588.thumb.jpg.935a63ab3e97c8354a37ee94dfd46f96.jpgHi all

 

I am fitting maxpeeding rods and have numerous questions

1 Inotice there is no oil way through the rod to the little end bearing I realise this is standard for maxpeed rod but why is it OK? 

 

2 The instalation instructions suggest moly bolt lube on the bolts.. Is this the same as molycoat(see picture) 

3 The bolts are 3/8 and the instructions state 45 ft/lbs but then state torque may change depending on application, has anybody fitted these and what torque was used. 

Thanks for help in advance

Adrian

1632499881140.jpg

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Not sure if this is identical but likely much the same. ARP assembly lube is easily obtained. I think it’s a mix of moly and graphite grease. 

The 45ftlbs is the recommendation with ARP lube. In theory they are stretch bolts so the most absolutely correct torque is what is required to achieve the exact stretch. Impractical  for most of us to do and the torque to 45 ftlbs is just fine.

The absence of a hole is indicative of the the rods not being drilled. I believe the drilling weakens the rods and splash oiling is considered adequate.

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Adrian,

To make your search for info easier you’ll find all your questions answered by using the search facility for Maxpeeding rods on the Tr3 forum. The threads there will produce information
This includes

Lube for the rods

Torquing the rods

The reasoning for the Maxpeeding rods not having a little end oiling drilling through the rod eg…

 

“One thing about the Maxpeeding rods is that unlike the original ST rods they have no oil feed to the small end, or the liners. I guess they rely on splash lubrication from the oil emerging from the big end being thrown upwards ? “

There is no direct pressure feed, the Triumph Conrod internal drilling and the liner oil hole midway up the rod are missing...thank goodness. I broke a race prepared rod when it fractured across the rod directly through the oil hole, On a stressed member it is likely to be the weak spot.
The Maxpeeding rods do have a small end oil hole which is directly on the outer curve of the little end about 3mm dia, Also inside the bronze little end, from the oil hole a cut oil distribution channel about 1mm deep around the circumference to distribute oil around the gudgeon pin.
As you say, the oil splash from the big ends and the general mist of oil being thrashed around inside is assumed to be enough for the other surfaces. There’s been enough of these sold now to assume bad results would have surfaced if the assumption is wrong.

Also

So just to be clear Peter, the stretch of the bolt when torqued to 45 lb ft has grown by 0.004 when measured in the conrod clamped...Yes ? 

So you are continuing to increase the torque clamped as recommended ?

..."If necessary increase torque until you reach the recommended stretch.

Once the bolt is stretched to the recommended spec, loosen the opposing bolt and retighten carefully until the recommended stretch is achieved."..

This should then give a torque figure which when applied to ALL the ARP bolts in the conrods should achieve an equalised stretch figure for the bolts that matches that specified as required by ARP. 

When the ARP bolts are then relaxed and undone they should return to their original non stretched length within a maximum of 1 thou increase.

All this info is no more than 4 months old and listed under Maxpeeding rods. If you have a question not answered there don’t be shy.

Mick Richards

Edited by Motorsport Mickey
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As Mick has stated.  
We set the torque to 45 ft lbs as recommended using lashings of ARP bolt lube. ( Remember to stir it up properly)   Stretch was 0.004” to 0.0045”.  We upped the torque to 48 ft lbs and recoated with the lube.   Stretch came in at 0.005 to 0.006    Continuous undoing and re-torquing with lots of lube, ( thanks for the tip Mick) brought all the bolt stretches to a consistent amount within the specified range.

I watched an USA video of bolt stretch checking and concluded I could make my own stretch gauge from an aluminium plate and a digital dial gauge, rather than shell out the thick end of £100.    I had to load the plunger of the dial gauge onto the bolt stem by the use of an elastic band or measurements were inconsistent  Simple solution.

I bought some slave cap screws to use for pre assembly so I was not likely to damage the ARP bolts, that are used in final assembly.  See in photo.

Peter W

image.jpeg.ea0b38cc2fb79935e644fed3b9e7c67b.jpeg

 

image.jpeg.e82d6822d2d8df6de566a82ea2692922.jpeg

Edited by BlueTR3A-5EKT
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On 9/24/2021 at 5:12 PM, Adrian Fuller said:

1632499907588.thumb.jpg.935a63ab3e97c8354a37ee94dfd46f96.jpgHi all

 

I am fitting maxpeeding rods and have numerous questions

1 Inotice there is no oil way through the rod to the little end bearing I realise this is standard for maxpeed rod but why is it OK? 

 

2 The instalation instructions suggest moly bolt lube on the bolts.. Is this the same as molycoat(see picture) 

3 The bolts are 3/8 and the instructions state 45 ft/lbs but then state torque may change depending on application, has anybody fitted these and what torque was used. 

Thanks for help in advance

Adrian

1632499881140.jpg

Any idea what size sockets are used on the 3/8  ARP bolts ????

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9 hours ago, roy53 said:

Was it mentioned that the rods can connect with the bottom of the liners which will need to be relieved to avoid this, or was that on the 6 cyl engine.

Roy

Bob completed part rebuilds checking the Maxpeeding rods for clearance on his 87mm liner rebuild and found good clearance that didn't require ANY relieving on the liners or other interior parts. Use the search facility on the Tr2/3/3a forum under the title TR3 Engine and gearbox rebuild. It comes complete with pictures.

Mick Richards  

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On 9/26/2021 at 8:48 PM, Motorsport Mickey said:

Bob completed part rebuilds checking the Maxpeeding rods for clearance on his 87mm liner rebuild and found good clearance that didn't require ANY relieving on the liners or other interior parts. Use the search facility on the Tr2/3/3a forum under the title TR3 Engine and gearbox rebuild. It comes complete with pictures.

Mick Richards  

I thought there was a post by Roger Murray-Evans which mentioned this issue, perhaps his was for a standard spec TR2 engine with 1991 liners .

Roy

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15 hours ago, roy53 said:

I thought there was a post by Roger Murray-Evans which mentioned this issue, perhaps his was for a standard spec TR2 engine with 1991 liners .

Roy

You are right Roy,

I used the MSRods but with 89mm liners in an early (non cam bearing) block.All the rods hit their respective liners and had to be relieved.(2 had already had a small lump chipped off whilst carefully rotating the crank!) It could be that the sources for the liners varies from supplier to supplier and have a longer spigot?.Mine came from TRGB.

Roger M-E

 

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Worked fine with original AE 87mm PowerMax liners.  Bags of clearance and that block had the liner seats cut 0.030” deeper due to corrosion and welding repairs 

Edited by BlueTR3A-5EKT
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very interesting, have just purchased the same set of the same rods ready to fit,   looking at the rods its not entirely clear which way they  are fitted  . Looking  at the crank with the engine inverted do the  conrod  numbers face the n/s or off side of the engine...its  not exactly technical but its the easiest to describe it  

cheers 

Steve

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Many Thanks Adrian  that's good enough for me . The  shot of the instructions were also very helpful as they were  missing from my set of rods

all the best 

steve

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On 9/29/2021 at 9:41 AM, roger murray-evans said:

You are right Roy,

I used the MSRods but with 89mm liners in an early (non cam bearing) block.All the rods hit their respective liners and had to be relieved.(2 had already had a small lump chipped off whilst carefully rotating the crank!) It could be that the sources for the liners varies from supplier to supplier and have a longer spigot?.Mine came from TRGB.

Roger M-E

 

Don’t think so when they were out of stock earlier in the year, they were out everywhere and I was told there was one importer for the 89mm liner and piston sets.  Might be different for those sets sold with forged pistons.

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On 10/3/2021 at 10:30 AM, Nobbysr said:

Many Thanks Adrian  that's good enough for me . The  shot of the instructions were also very helpful as they were  missing from my set of rods

all the best 

steve

Hi you might find the detail on piston ring gaps in my post on Bastuck rear oil seal useful. 

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  • 4 weeks later...
On 9/25/2021 at 9:57 PM, Nobbysr said:

Any idea what size sockets are used on the 3/8  ARP bolts ????

Sorry for late reply 

7/16” AF 12 point or bi-hexagon socket.  


I had to buy a replacement as I exploded my old Britool one that I had ground the wall thin on to fit a certain application in the past 
I bought 3/8 sq drive as that enables me more clearance over using the heavier and more agricultural 1/2” drive.  Personal choice of course to match with other tooling.  Look at Snap-On F141 or SF141 for deep pattern.

 

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Thanks Peter

Oddly i had the same issue my issue was cheap socket..  but picked up a Brittol one second hand on Ebay 

I had a real pain in the proverbial with my ring compressor  which slipped the gear ratchet  every time i tapped the piston down..  A Draper one arrive 3 days later   and was a significantly better device .. you'd have thought that i would realised  by now that you get what you pay for

all the best 

Steve

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A Draper one arrive 3 days later   and was a significantly better device 
 

How bad was your original !

Mick Richards

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