Which would you buy.......opinions please

Which would you buy.......opinions please

Author
Discussion

Green George

316 posts

251 months

Sunday 3rd September 2017
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V7SLR What is your view on an apollo tank equipped VHPD?

What is the service interval on a scavenge pump? Presumably this can be done by a 7 specialist.

Edited by Green George on Monday 4th September 18:23

pmason74

Original Poster:

68 posts

208 months

Sunday 3rd September 2017
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Thanks V7SLR for the tip re: dry sump maintenance, when I see the cars (3 of the ones I am now looking at are dry sumped) I can review the history to see if I can see if this has been done

g7jhp

6,964 posts

238 months

Monday 4th September 2017
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V7SLR said:
g7jhp said:
My perception (rightly or not) was that the K-Series Superlight R is more stressed and I'll heard of more issues.

The Duratec R300/ Supersport R/ 360 R with 175bhp seems most reliable, but these cars have a higher entry point (unless you can find a higher mileage example.
The vhpd engine in the SLR is not particularly stressed, the issues that have arisen are usually related to oil starvation due to the dry sump scavenge pump not being regularly overhauled, the belltank level doesn't keep up with what's needed eventually resulting in bearing failure .... this is applicable to any high powered K-Series Caterham with the Caterham belltank dry sum setup. Keep it maintained and all should be okay.
I was aware it had something to do with the dry sump, thanks for the explanation V7SLR. smile


V7SLR

456 posts

186 months

Monday 4th September 2017
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Titan who made the scavenge pumps will refresh them at a cost of around £100 (last time I had mine done).

Assuming the oil level is correct, if there's some dropping of the oil pressure under heavy breaking, the scavenge pump needs a refresh.

pmason74

Original Poster:

68 posts

208 months

Monday 4th September 2017
quotequote all
V7SLR said:
Titan who made the scavenge pumps will refresh them at a cost of around £100 (last time I had mine done).

Assuming the oil level is correct, if there's some dropping of the oil pressure under heavy breaking, the scavenge pump needs a refresh.
Many thanks for the info V7SLR - will be useful as a couple of cars I am looking at (next week) are dry sumped (and guessing it will be the Caterham system) and one is an Apollo installation. To be honest, for my use I suspect the dry sump is overkill as my meagre cornering speeds on account of limited bravery/talent will not create much centrifugal force, but if they come with it, so much the better and if I ever did take to a track (although unlikely) there's peace of mind its all covered

Also be looking at a very nice looking Duratec car later this week which has an epic looking spec - I'm very lucky in being somewhat spoiled for choice!

Appreciate everyone's help and guidance

Green George

316 posts

251 months

Monday 4th September 2017
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What is the consensus from those in the know about a VHPD K using an Apollo tank as opposed to a dry sump system for mainly road use and 4 = 5 track days per year?

I have an Apollo tank on my Superlight which I like. As I understand it when the oil pressure drops for example in a right-hand bend the reservoir of oil in the tank keeps the engine supplied with oil until the pressure picks up.

V7SLR

456 posts

186 months

Monday 4th September 2017
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Get a dry sump.

Red Seven

156 posts

197 months

Monday 4th September 2017
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Green George said:
As I understand it when the oil pressure drops for example in a right-hand bend the reservoir of oil in the tank keeps the engine supplied with oil until the pressure picks up.
No. The function apollo tank is to de-aerate the oil. It's plumbed after the pump, so, if the pump has nothing to suck, there will be no pressure out.

DCL

1,216 posts

179 months

Tuesday 5th September 2017
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Red Seven said:
Green George said:
As I understand it when the oil pressure drops for example in a right-hand bend the reservoir of oil in the tank keeps the engine supplied with oil until the pressure picks up.
No. The function apollo tank is to de-aerate the oil. It's plumbed after the pump, so, if the pump has nothing to suck, there will be no pressure out.
But it is worth saying that the crank acts like a big centrifugal pump, and as long as the oil is flowing it will tend to be sucked up by the crank. But far from ideal for the mains and valve gear.

Red Seven

156 posts

197 months

Tuesday 5th September 2017
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DCL said:
But it is worth saying that the crank acts like a big centrifugal pump, and as long as the oil is flowing it will tend to be sucked up by the crank. But far from ideal for the mains and valve gear.
I think it gives unrealistic hope to suggest that the crank acts like a pump.
The bearings need oil pressure, not a little splash.

In a wet sump K Caterham, the crank splashing in the oil creates foaming of the oil. The Apollo tank significantly reduces this aeration of the oil, but it does nothing to stop dips in oil pressure due to oil surge.

DCL

1,216 posts

179 months

Tuesday 5th September 2017
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Red Seven said:
I think it gives unrealistic hope to suggest that the crank acts like a pump.
The bearings need oil pressure, not a little splash.

In a wet sump K Caterham, the crank splashing in the oil creates foaming of the oil. The Apollo tank significantly reduces this aeration of the oil, but it does nothing to stop dips in oil pressure due to oil surge.
I think you've missed the point. The oil in the galleries within the crank web are exposed to very high G forces and that pushes the oil outward towards the big end. If the column of oil is unbroken then that will continue to supply the big ends. Oil pressure has nothing to do with the hydrodynamic pressure that separates the the bearing surface - it's merely the means to deliver the oil to the bearing. I could bore you all with the pros an cons of cross drilled cranks but . . . (yawn)

Further more, if the oil pump is not pumping oil, then it will be pumping air, and that will maintain some pressure in the Apollo tank. So the Apollo tank is good news all round, and does provide a degree of protection against surge.

Krismuss

92 posts

187 months

Tuesday 12th September 2017
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The green Tracksport was mine before Knight's and is a very well sorted 7.

Coincidentally, I sold it via S&C to fund an SLR (No.127), which three years later is still a 'work in progress'.

If I compared the two, I'd say the Tracksport was infinitely more sensible, fun on the track but not much top end on faster circuits (not that I did many), whereas the SLR more than makes up for my lack of driving ability!

Rear diff makes a massive difference too, the tracksport came with a 3.9 diff when I bought it and I instantly changed to 3.6 which was probably the right decision for that car, however, my SLR runs the 3.9 and I wouldn't have it any other way, the acceleration is ballistic!

If you want to know any more about the Tracksport let me know as I know most if not all of its history.

Chris

pmason74

Original Poster:

68 posts

208 months

Saturday 7th October 2017
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Just wanted to say a very big thank you to everyone who has given advice both on here and the myriad of PM's I've sent out asking for various bits of info and advice subsequently

Today, I have placed a deposit and it's not on any of the cars I originally asked about! Have seen some fabulous cars and in the end have gone for one which I didn't think I ever would and not one on my original must have's list

But, today, despite my head saying otherwise, I was bowled over by the look of a particular car and then driving it made everything else go out of the window. Felt so right, felt confident and comfortable driving it, felt absolutely spot on, so ignored my head and just did it! Not sure what it was about the car, but it just clicked and I knew it was "the one"

Thanks again everyone, and the Caterham ownership experience starts again! (Well in a week or so anyways!)

pmason74

Original Poster:

68 posts

208 months

Saturday 7th October 2017
quotequote all
Just wanted to say a very big thank you to everyone who has given advice both on here and the myriad of PM's I've sent out asking for various bits of info and advice subsequently

Today, I have placed a deposit and it's not on any of the cars I originally asked about! Have seen some fabulous cars and in the end have gone for one which I didn't think I ever would and not one on my original must have's list

But, today, despite my head saying otherwise, I was bowled over by the look of a particular car and then driving it made everything else go out of the window. Felt so right, felt confident and comfortable driving it, felt absolutely spot on, so ignored my head and just did it! Not sure what it was about the car, but it just clicked and I knew it was "the one"

Thanks again everyone, and the Caterham ownership experience starts again! (Well in a week or so anyways!)

bcr5784

7,109 posts

145 months

Saturday 7th October 2017
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Intrigued! What have you bought?

pmason74

Original Poster:

68 posts

208 months

Saturday 7th October 2017
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A red (not a preferred colour of mine at all but looks stunning on this car), fairly extensively upgraded (again, not something I was looking for) supersport. Fantastic looking and brilliant to drive so I had to do it.


rubystone

11,254 posts

259 months

Saturday 7th October 2017
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From sevens and classics, looking at that picture...

Green George

316 posts

251 months

Sunday 8th October 2017
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Congratulations, that is a very nice looking car.

pmason74

Original Poster:

68 posts

208 months

Sunday 8th October 2017
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Thank you Green George. Would never have thought I would have liked a red car, so surprised when I liked the look of it so much.

Stridey

342 posts

107 months

Sunday 8th October 2017
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That looks lovely. And I've nothing but nice things to say about S&C too. Well done and enjoy!