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TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Sunday 14th October 2012 quote quote all
I should stop this reading bit... Have been looking tonight at this...

http://books.google.co.uk/books?id=gmSavy1RPxEC&am...

bottom of page 36 onto 37 its saying max power is produced at 75 deg c?.. it so I'm going to get MA to re-do my chip and lower my temps?......

What everyone else running??

spend

12,468 posts

137 months

[news] 
Sunday 14th October 2012 quote quote all
74C has been my target for years....


TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Monday 15th October 2012 quote quote all
Interesting.... Mark Adams will say 'run it as hot as you can' but then you read about bearing cap issues and the obviouse liner problems... I'm assuming he's doing this to get rid of things mixing with the oil like any un-burnt fuel etc.. but my oil gets changed every 2000 miles or so anyway so is it a problem??...
I may ask him to mod my chip to take it off fuel enrichment at 70 deg?..

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Tuesday 16th October 2012 quote quote all
Had a word with Mark yesterday... his concern was water in the oil .. and the hotter you get it, the easier it boils off....
Happen cross bolting is the best fix laugh

spend

12,468 posts

137 months

[news] 
Tuesday 16th October 2012 quote quote all
Mapping the water temp to various spot temps around the engine is very complicated.

Same applies to oil temps as well.

Maybe good crankcase ventilation is more important than water temp for preventing water (& acids) in the oil? Are you really going to believe that 75C vs 82/5C water temp near the stat is making that much difference to the oil temp in the crankcase? Even when the temps are high enough to 'boil off' the water it will only condense back in again as the engine cools unless you have positive ventilation drawing it out. Also remember the correct Positive crankcase ventilation is creating vacuum in the crankcase - so the water will boil off at lower temps.

Arguably the larger crank in cross-bolted blocks is stealing block material that holds the vee together... which is one of the oft proposed causes of the liner problems (coupled with the higher temps those engines run at).
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TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Tuesday 16th October 2012 quote quote all
Yes… I guess to can read a lot into scenarios without it actually happening… as you say a reported 85 or 90 deg water temp at the stat.. who knows what it will be at the mains or what the liner will see. I may bring it down a tad or run my 82 stat with 84 otter.. I know the fans will be on a lot but not sure I like seeing 90!

I want to clean the engine up this winter so will make these changes but I think one of the key areas to preserve bearings and may be even the crank on small journal motors is the have the thing internally balanced?... That way internal harmonics are not as lightly to start up and cause problems…



spend

12,468 posts

137 months

[news] 
Tuesday 16th October 2012 quote quote all
TVR Beaver said:
I want to clean the engine up this winter so will make these changes but I think one of the key areas to preserve bearings and may be even the crank on small journal motors is the have the thing internally balanced?... That way internal harmonics are not as lightly to start up and cause problems…
Rarely commented upon is the harmonic damper - read cruddy bit of tatty rubber band.... Fitting a proper fluid damper is the best way to dampen the nasty things going on in the crank AFIK (and ensure it always works as the ring in fluid won't deteriorate like the glued rubber). Don't be fooled by some of the 'competition' dampers offered by well known suppliers they are still rubber bands.


TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Tuesday 16th October 2012 quote quote all
Would you have any recomendations for units that fit at all smile

spend

12,468 posts

137 months

[news] 
Tuesday 16th October 2012 quote quote all
I used 6.25" Pontiac fluid damper as a basis since its the same bore to suit the crank nose...

Required:

Keyway recut to suit timing marks.
Rear shortening to sit correct depth.
Different size oil seal.
Pulleys redrilled to suit bolt pattern.
Timing cover ground out to allow clearance.

I think however real steel sell one ready to fit?

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Tuesday 16th October 2012 quote quote all
cheers Dave.. great info.. will take a look!
so your a supporter of the smaller journal crank are you?.. I'm guessing you got yours internaly balanced?

spend

12,468 posts

137 months

[news] 
Tuesday 16th October 2012 quote quote all
Not really fussed John, probably just prefer the small journal (fatter block bottom). Having the crank bigger (heavier + increased bearing speed although spread load ((not in proportion to diameter unfortunately) than required for strength needed just seems a bit pointless?

However strong you make it the crank is still likely to be flexible IMO, so damping the nasty harmonics effectively would seem more sensible than trying to make a crank bigger & stronger? Obviously the better balanced the smoother it will run, both of these will result in an effectively stronger crank & longer lasting bearings I reckon.

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Tuesday 16th October 2012 quote quote all
Have mailed Real Steel so see what they come back with... I'm with you.. it's amazing how detrimental frequancy vibration can be... When I worked in Aerospace we did a lot of work in this area (obviously).. and you can actualy drill holes using a solid piece of steel if subjected to the right frequancy.. so what indeed could it do to a crank....

Internal balance and a good damper as you say yes

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Thursday 18th October 2012 quote quote all
Hi John!
No sorry we can't help with this as we do not stock any type of fluid dampers.
Thanks!
Regards... Mark.
..........................

So nothing at Real Steel?....

Simon says

11,446 posts

107 months

[news] 
Thursday 18th October 2012 quote quote all
What about the JE Dev Competiton Harmonic Damper then? winkhttp://www.johnealesroverv8.co.uk/9.html

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Thursday 18th October 2012 quote quote all
Not sure how it works?.. is it rubber or fluid??

spend

12,468 posts

137 months

[news] 
Thursday 18th October 2012 quote quote all
spend said:
Don't be fooled by some of the 'competition' dampers offered by well known suppliers they are still rubber bands.

Simon says

11,446 posts

107 months

[news] 
Thursday 18th October 2012 quote quote all
Thank you Dave thumbup I run a 74 degree Wahler stat (I am a fair weather user only) which according to the MS software my running temps are usually around the 78/82ish rolling and I am content with this wink

ChimpofDarkness

4,618 posts

65 months

[news] 
Thursday 18th October 2012 quote quote all
With an 82c thermostat my Canems software displays a consistent 95c at hot idle.

The hottest I've seen it go is 98c about 5 seconds after the fans have cut in, at which point it immediately starts to fall to a low of 92c, before settling back up to 95c (all at idle).

On the move it holds a very consistent 88c on a cold day & 92c on a hot day.

The TVR gauge responds significantly slower to temperature rise than the Canems software displays during the warm up phase.

Remember the gauge & ECU have their own separate dedicated senders, I'm using the better Range Rover temp sender tuned to the TVR gauge with a variable resistor.

When the TVR gauge eventually catches up, it displays a figure that's almost exactly 10 degrees lower than the true coolant temperature displayed on the Canems software.

Actually I chose to set it up this way because it suits the gauge scale better & it's easier to add 10 wink

Some may prefer to run a cooler true temperature than my fan regulated 95 but I've had no issues with my car overheating even in South of France ambient temperatures of 40 degrees plus.

This year between Montpelier & Carcassonne I got stuck in the mother of all stop start crawling traffic jams on the hottest day of the year, with no issues whatsoever.

I tuned my nose to it's highest sensitivity fully expecting that tell tale sweet smell of cooking ethylene glycol to start wafting into the cabin, but I'm pleased to say it never came and true figure never rose beyond 98c on my netbook screen.

I was always taught; cooler for performance, hotter for economy.

And for safety never let your coolant go over 100c, most healthy engines (even old ally ones) with a good fresh antifreeze mix & a decent pressure cap can run up to 110 degrees before you start running into issues.

Just remember, if you're taking your coolant temperature readings from the TVR gauge and it's still using the original TVR located sender you will not be seeing anything like the true picture.

TVR Beaver

Original Poster:

2,653 posts

66 months

[news] 
Thursday 18th October 2012 quote quote all
Mmmm Sounds like your system as you say is reading a tad high... With an 82 stat on the motorway and a cold day you will probably find the stat starting to close to keep the engine temp up... so it’s strange you are seeing 88 deg.. I would have thought more like 78 / 80 deg?
The reason for not running the engine too hot is to stop expansion especially around the crank and mains. If blocks are not cross bolted you can have gaps opening up that allow the caps to move and in turn can wear out their locations and / or crack. also you can have liner problems the hotter you go also...
It's all in the balance as to what end you support... Hot runs the risk as above... but too cold messes the oil up which in turn can then be detrimental to your engines internals....
I guess there is no right answer but if you are actually running at the temps your stating, it may not over-heat, but I would be careful as to what else it could be doing internally... smile

Simon says

11,446 posts

107 months

[news] 
Thursday 18th October 2012 quote quote all
I use to run a serious Ford X Flow with a 74 degree stat (Jag) and an oil cooler with dual to atmosphere crank case breathing and never had a problem with moisture/mayonnaise in the oil scratchchin I dont see why the RV8 would in these cars as the engine is well insulated from the outside air/cooling anyway and the crankcase ventilation is not bad either which helps avoid the problem wink short runs and those silly winter starts in storage that some owners insist on are what puts nasties into the oil rolleyes if you don't intend to take it out for a proper run leave it alone it won't seize up or dry out whistle

Edited by Simon says on Thursday 18th October 17:07

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