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v6Max Clio Build Stuff

Not much that's interesting has been going hence no recent updates but..

I had some panels anodised - these panels carry the power and signal connections through the bulkhead. All cut on the little CNC machine then surface prepared in my tumbler prior to anodising. The big connections in the foreground are power, the ones in the background are power feeds to things like lights, horn etc and signal to battery master, brake fluid warnings etc.
[album]4385[/album]

Now I'm getting dangerously close to testing all the loom(s) I went out and collected a temporary heart for the Clio - it'll allow me to test everything electrical including what happens under and over voltage. I should have the programming for the ISIS complete next week so either I'll be posting again or I'll be in orbit above Dover due to an unfortunate wiring incident.
[album]4386[/album]

This is the tandem master cylinder for the car - replaces the existing master cylinder and gives me 2 master cylinders, one for rear and one for front brakes with a balance bar. Nicely(ish) made although needed some "fettling" by a tame machinist I know. As per usual the experience was somewhat sullied by the quoted 3 week delivery time turning into... once again 6 months.
[album]4384[/album]

Work that is in progress at the moment includes full set of drawings for completely re-designed gear stick and linkage mechanism - may have something to show by Christmas.

And hidden at the bottom of this post is the bit engine people will be interested in; the replacement pistons we brought were deliberately oversized so we could increase the compression ration. They've now been milled down to gives us a compression ratio. above 13:1.

Yes - there is a knock sensor, yes it is 3rd party management and yes when it's dynod I'll take some pictures so you can witness the look of fear and abject disappointment on my face as the rods make a bid for freedom from the block at around the same time the heads travel through the roof of the dyno-cell :-o
 
"short" engine has finally been put back together - I should have taken pictures I guess but I'd passed out from the shock of something actually happening as I'd actually gone down to officially call the project off.

Anyhow - I've recieved some re-assurances that the heads will be back on this week but it was nice to see at least part of it back together. The custom pistons looking particularly fine. New Trophy mains went in and some Mercedes bearings found their way into the engine as well.

Kind of OT and yet not because it's about Renaults - part of the delay has been the magical ability for well heeled racers to jump the queue. A customer with a Clio 200 Cup had dropped his car off for some development at the end of last years race season. Now bear in mind we're talking about a 2 litre 4 cylinder naturally aspirated engine here ...

The engine was dynoed 2 weeks ago and I've seen the run - 279.2 bhp at 7.5kRPM - this is not a rolling road, this is a proper engine dyno. The engine sits on a special cradle coupled to a water brake assembly which needs a huge water tank and and an external cooling tower to handle. The dyno is calibrated very accurately and you can't supply "magic" numbers to it (e.g. claiming the ambient temp was 100 degrees or that drive train losses were 200 bhp).

That this particular engine then did 100 laps at BH during testing and was run on the wrong fuel (95 ron!) and didn't consume itself is even more impressive - I'm hoping this is a good sign and that my tenacity/patience may be rewarded.
 
Great to hear you've had some progress. Have you got any idea what the final weight of your Vee when it's reconstructed? It
will be great to have an estimated power/weight when the engine is dyno'd...
 
I've no idea to be honest but if it finally gets done I will know for certain because it will be corner weighted during setup.

I will elaborate a little more on my expectations though with regards the engine which may cause some debate because in doing so I'll be unable to avoid expressing some contentious opinions so here goes:

So as we know the Phase 1 version of the v6 had a stated power of 230bhp with anecdotal evidence suggesting that once packaged in the car it actually produced something around the 220bhp mark. This is pretty understandable given that Renaults' figures would have come from an engine on a dyno where considerations such as packaging, airflow and air temperature, having the AC turned on or the stereo turned up etc would not be a factor.

The Trophy engines had more "engineering" thrown at them, ran Magnetti management where the focus was on performance and not on getting value for money from 95 ron petrol. The heads were different, induction and exhaust was completely different - twin TBs, much better plenum design due to not needing to meet with certain packaging constraints imposed in the road car, no catalytic converters, different CAM profiles (both inlet and exhaust), different inlet ports and a lighter flywheel. There were probably other differences but that's enough for now.

With these changes the Trophy's made 280bhp so a 50bhp uplift on the production engine which is very significant (say around +20%) given we're talking NA here - so on my engine the changes are broadly similar: multiple TBs using the Trophy plenum, Trophy spec inlet and exhaust cams, custom pistons to lift CR, lighter flywheel and 3rd party management - my expectation is 280ish and that's it.

I'm being realistic here - I have a problem believing that 3rd party management + improved exhaust = +300bhp which would represent a 50bhp uplift over a Ph2 engines' stated output which dont' forget is already apparently delivering a +20bhp uplift over the original engine due to revised induction and some other changes. I get asked the question about how much power quite often and I know some people will be surprised that I'm not claiming it's going to be 330bhp and I'll be looking like JC driving an Arial Atom everytime I go to the shops in the car but my opinion is based on a few things:

1) Look at what the Trophy cars actually made and understand that this was with a lot more engineering and an understanding that they were built to race and not survive 120k miles day to day driving with 20,000 mile service intervals

2) Does it sound likely that Renault designed an engine with so many inherent design flaws that finding an additional 50bhp is just a matter of changing the ECU and bolting on a few bits and some shiny pipes?

3) There were later versions of the the trophy engine and I know a team that were running an engine purporting to deliver something towards the high end of 380bhp - it never finished a race and broke down continously and beared little resemblance to the original engine by that point

To expand on what those changes are on my car just so you get a sense of what I mean by "considerable engineering":
1) Completely re-desgined inlet using ITBs grafted to the Trophy inlet plenum - custom designed and cut in house
2) Inlet -> Head spacer/mounting plate - custom design designed and cut in house
3) Completely new fuel rail, injectors, fuel system - custom designed and cut in house
4) 4 new cam covers to accomodate revised oil filler mounting point, oil drains and new inlet design - custom designed and cut in house
5) Trophy "spec" inlet and exhaust cams with removal of VVC mechanism requiring new cam pulleys and various custom bungs
6) Re-bored block (slight rebore to address bore wear thought to be due to bore wash)
7) New custom pistons - re-profiled and cut in house
8) New mains/bearing, rod bolts
9) Extended sump
10) Lightweight flywheel - not lightened a brand new custom cut lightweight flywheel one piece design
11) 3rd party management

Yes all that and a bunch of detail stuff I didn't include and I'm still "only" expecting to hit 280bhp but then I think that's realistic but does demonstrate what I mean about the sort of engineering I think you actually have to do to gain the sort of power gains some are attributing to far, far less.

As I said some of this attitude is down to not believing that Renault/Citreon/Peugeot actually designed such an appalling engine that 50bhp is in there just dying to be let out and also knowing what the Trophy's made alongside of an appreciation of what compromises you make when desiging a race engine and how those compromises simply would not be compatible with most peoples needs from an everyday car.

Obviously there's a part of me that would love to wrong and that if the engine finally bursts into life it's shown to produce 1gigabhp but in reality I think my expectation is realistic and if it's gets close to that point I'll actually be a happy v6 driver.

I also hope that I'm wrong for the sake of others who have, like me, invested time and effort in these cars but again I've got a sneaking feeling that my cynical attitude to claims of pulling the siginificant kinds of power increase out of the existing engine without very significant engineering (as per the Trophy engines or going down thje FI route) is perhaps correct.
 
Follow Colin Chapman's ethos to "add lightness" and ultimately BHP becomes less relevant anyhow.

280 reliable bhp is better than 320 unrealiable bhp. I'd imagine with a completely stripped out interior/mags/perspex etc with fluids and driver onboard you've got to be getting close to around 1,150kg, which comes out to around 245bhp/ton, which is up about 80bhp/ton on a standard ph1.

Substantial, (hopefully) reliable gains :approve:
 
You wait years for 1 photo then you get 6 at the same time

Seems like one of my motivational talks has had some results and spanners have been found and even wielded in earnest:

Cleaned block ready for rebuild - see those shiny shells? They took nearly as long as the last ice age to get hold of
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Rods ready for crankshaft
[album]5206[/album]

Crankshaft goes back in
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Extra special pistons (well they came all the way from Argentina so I guess that makes them special)
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Another view shows how they've been machined down (that's how they tuned the CR)
[album]5209[/album]

Can this truly be a head!
[album]5210[/album]

I'd prefer 2 but I settle for one for now
[album]5211[/album]
 
Yummy!
That's one shiny engine block. I can't wait to see the final install! Keep up the momentum fella!
 
I'm not sure Oldskool = I'm braving a visit to the builder and will ask him - looking at my list of things I've paid for I don't see any mention of new rods so I suspect OEM rods.
 
Thats fair enough Max. It was just that when I looked at your bottom end pics, they didn't look to be the i or H beam type. Not that there's anything wrong with that I'll add as I'm sure they are up to the job if they are in there. Would just be nice to know that the OEM ones are up to abit more abuse. :approve:


Everything looks awsome by the way. Top stuff.
 
Oldskool - they're are the standard rods, I've been assured they're good enough for NA without stupidly high rev limit, bolts are not oem; ARP.

I did what I always do, even though I know it's a mistake, and engaged in a full on conversation/discussion about the engine and for some reason we went from how the new cam covers are being cut to finding a large 6082 T6 plate to make a sump spacer plate to lowering the engine in the car to get the COG lower to considering dry sumping - why can't I keep my mouth closed?

When I proposed dry-sumping the initial reaction was in the form of "f**k that" but then we got talking about the potential benefits in terms of allowing much greater oil volume, some easier plumbing/routing for oil drains and the possibility of dropping the engine by 25mm -> 50mm.

Probably won't happen because I can see the cost being very high if there's no existing sump design "out there" but we'll research it anyway.
 
I agree with Tim too Max. As good as both ideas are they are big changes to something that is no doubt coming together nicely.

Just out of curiosity Max, if you do go ahead with it, lower the engine in the shell and then lower the ride height, would it not effect the driveshaft pot joints?
 
That was one of the concerns about the idea - you could end up with the driveshafts running at extreme angles but we're not talking about a massive change here; 50mm is probably not really achievable it would more likely be 25mm and at that the angle change would not be huge. Driveshafts are going to an "issue" whatever I do because I've got to go from production gearbox on one end to Trophy hubs on the other.

What would be useful... can any one measure the gap between the underfloor and the bottom of the sump - this is what will ultimately determine the practicality of lowering the engine; the 2 lowest components being the sump and the exhaust from the front bank.

Going for a dry-sump is not neccessarily a pre-requisite of lowering the engine. I mentioned it because the conversation originally started from a viewpoint of how to make the sump bigger to increase oil volume (which we'd do via a 25mm spacer plate) - although as I typed this it's reminded me he's clearly forgotten about the oil cooler + associated pipe work which will increase oil volume anyway.

I think the "right" solution will likely to be to accept that we can yield a decent volume increase from the oil cooler + pipework and look to drop the engine by +25mm which will yield a small, but worthy, lowering of the weightiest component (other than me lol) but not require the massive expense of going down the dry sump route.
 
2 images; one an STL model the 2nd the actual object in 6082. Can you guess what it is?

STL
[album]6040[/album]

6082
[album]6041[/album]
 
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