JPS Project

[Djs44]

20 minutes ago, LOTUSMAN33 said:

I would get the socket machined on the lathe to remove the chamfer, had to get this done a few times over the years. 
Any machine shop will oblige as literally a couple minutes work in a 3 jaw Chuck.

Dave  

Machine my sockets ? How very dare you . 😂

[Fridge]

I'm still investigating what options I have for the 907 engine to make improvements without going to far.

I'd like to improve the cam timing side of things by upgrading to HTD pulleys and the uprated cambelt. I've been advised that the Gary Kemp tensioner is better than the semi-automatic version that I fitted. I think that this is only available in manual form and that fitting requires a conversion.

I'm also not sure about switching to a lightweight flywheel, which may improve accleration and general drivability within usual driving situations.

I think I'll get the distributor refurbished also whilst I'm at it. It was converted to Luminition Magnatronic and works well, but I suspect it's ready for an overhaul. Along with the one from my other classic, which will remain on points.

I need to ask around and see what is best. I had considered the possibility of upgrading further, but having now driven the car, the engine is quite rorty with a good turn of speed. Certainly for me, and I don't need to chase a load more horsepower.

[drdoom]

I can relate the views shared by one mate, a long time Esprit S1 owner and enthusiastic supporter of the 907, who worked the lump up from humble Federal tune to something better. Step one was to convert carbs to 45DCOE, change pistons to DOM spec 9.5 and flip the inlet cam wheel to red dot timing. This brought joy, particularly in the upper range, so further work included big bore 4-2-1 manifold with various silencers tried, aftermarket 10.5 pistons and the flywheel lightened sensibly. Ever more pleased with the car's performance but pressing on nonetheless a dry sump MBP was adapted and aftermarket pump/tank added quite successfully. Notable change in the engine's power curve was realised with a change to 104 ( green dot ) timing on new HTD wheels and belt with a sense that the engine wanted an earlier change of gear when given its head. Both chaps I've known to run these cars locally found the red dot timed 907 wants to rev out skyward with shift points in mid-upper 7k's when allowed to breathe well, fine on track but less than ideal in traffic. So it seems that 104 timing yields more mid range grunt, predictably moving peak torque to a lower RPM point and liking shift points sub-7k during full-on runs. FWIW.   

[Fridge]

Fortunately euro cars have decent carbs to begin with.

I need to do more investigation, but I don't rev any of my cars to anything like 7,000rpm. As I live in North Yorkshire not Laguna Seca.

[Djs44]

Deposit going down on new engine tomorrow

[LOTUSMAN33]

Brilliant, what did you go for in the end?

This is going to be a cracking JPS when finished!

Dave  

[Rudi K]

On 06/10/2020 at 17:34, LOTUSMAN33 said:

They have a single dash mount woofer Offset from centre, the leather trim in front of the screen should be perforated with lots of holes, the Oval speaker sits behind.

SJ sell the looms but I’m sure I came across another place doing the old google search when I looked.

Dave  

Hi @LOTUSMAN33. I do not seem to be able to hear any sound from the woofer in JPS #40, although the two door speakers (non-original) work. The Service Parts List for the JPS indicates that there should be a crossover unit fitted. Any idea where it should be located and any thoughts on trouble shooting a silent woofer?

[LOTUSMAN33]

I am tackling my dash build over Xmas and replacing the stereo along with aerial, I will investigate for you then 👍

Dave  

[Djs44]

17 hours ago, LOTUSMAN33 said:

Brilliant, what did you go for in the end?

This is going to be a cracking JPS when finished!

Dave  

2.5 l from Lotusbits inc their exhaust , mapped ignition ,light weight flywheel - will keep the original engine as is .

Since having a red top Vauxhall engine on carbs in a Westfield I've always fancied a really nice all steel n/a engine on carbs ... bring it on. 

I also checked the chassis squareness the other night and it all seems good - I have a slight bend in one of the lower rear wishbones so I think I'll replace both to be sure. 

On 21/11/2020 at 17:28, Fridge said:

Fortunately euro cars have decent carbs to begin with.

I need to do more investigation, but I don't rev any of my cars to anything like 7,000rpm. As I live in North Yorkshire not Laguna Seca.

Having driven modern diesels for years I know what you mean about revs . In contrast, after a winter of not driving my bike-engined single seater I always wonder why it seems slow reving to 8000rpm  and then realise it pulls to 12500rpm

[Fridge]

Do they recommend upgrading the engine mountings to account for the greater torque?

[Djs44]

Dave 

I did check and the answer was no. Is it just the rubber elements on the uprated mounts or brackets etc too ? 

[drdoom]

That 2.5 should be more than the original biscuit style mounts will withstand, if driven with spirit. 

 

[v8vantage]

Would also make sure the driveshaft UJs are up to spec with all the extra power. LotusBits does the stronger version of UJ so pick some of those up with the engine. In the USA Claudius does the uprated engine mount as well as a weld in kit for adding an upper link to the rear suspension so all the loads are transferred from the driveshaft. I have their engine mounts on my "JPS", essentially the turbo mounts adapted for use on the 907 engine. 

[Djs44]

26 minutes ago, v8vantage said:

Would also make sure the driveshaft UJs are up to spec with all the extra power. LotusBits does the stronger version of UJ so pick some of those up with the engine. In the USA Claudius does the uprated engine mount as well as a weld in kit for adding an upper link to the rear suspension so all the loads are transferred from the driveshaft. I have their engine mounts on my "JPS", essentially the turbo mounts adapted for use on the 907 engine. 

I am having Dana u/j’s fitted and will investigate the engine mounts following comment here thanks 

[skiing]

I would definitely recommend the flywheel and exhaust from Lotusbits - I have them on mine and it sounds fantastic and goes very well. Mine is also a High Compression engine standard so not the full 2.5 with all the extra goodies but I bet it will be a lot of fun. 

[Fridge]

40 minutes ago, skiing said:

I would definitely recommend the flywheel and exhaust from Lotusbits - I have them on mine and it sounds fantastic and goes very well. Mine is also a High Compression engine standard so not the full 2.5 with all the extra goodies but I bet it will be a lot of fun. 

Since I understand that Gary Kemp did a lot of the development work, the flywheels and internal upgrades are available direct from him. He sells direct through eBay.co.uk 

[EXCEL V8]

21 hours ago, v8vantage said:

Would also make sure the driveshaft UJs are up to spec with all the extra power. LotusBits does the stronger version of UJ so pick some of those up with the engine. In the USA Claudius does the uprated engine mount as well as a weld in kit for adding an upper link to the rear suspension so all the loads are transferred from the driveshaft. I have their engine mounts on my "JPS", essentially the turbo mounts adapted for use on the 907 engine. 

Presumably you need plunging drive shafts with the upper links - is that a spline collar I can see in the photo?  I can't see any details on their site, but looks very interesting.

Pete

[Djs44]

Little progress on the car but bought this recently 

Test car kept blowing fuses , lol 

Also bought this 

but ended up drilling the boot lock bolt out. 
How do you get the boot catch out ?? 

[Fridge]

The catch comes out from behind the body shell luggage area lip. Towards the number plate, then out and away. Assuming you have removed the thread machine screws and your boot boards of course. 

Edited November 27, 2020 by Fridge

[Djs44]

21 hours ago, Fridge said:

The catch comes out from behind the body shell luggage area lip. Towards the number plate, then out and away. Assuming you have removed the thread machine screws and your boot boards of course. 

I can’t get it out . The catch bit won’t come through the body 

[Fridge]

It pushes in, then out.

However it is just over 4 years since I removed mine.

Is it just stuck in place? You've removed the three machine screws.

[Djs44]

I've been cleaning the seat covers every so often and they are starting to look ok . 

I get a feeling that the gold always shows shadows such that it never looks consistent but I'll keep trying .

Before and after . Leather off to be redone starting this week along with the dash etc . 

 

Still can't get that pesky boot catch out ....

[LOTUSMAN33]

They are coming up well, what are you using?

Dave  

[Fridge]

Wow. They're coming up great.

Thought about getting them finished professionally?

[v8vantage]

2 hours ago, Djs44 said:

I've been cleaning the seat covers every so often and they are starting to look ok . 

I get a feeling that the gold always shows shadows such that it never looks consistent but I'll keep trying .

Before and after . Leather off to be redone starting this week along with the dash etc . 

 

Still can't get that pesky boot catch out ....

After vacuuming the seats, I then get the steamer out and hit the fabric with some steaming hot goodness. Next I use a solution of Windex window cleaner ( the one with ammonia) mixed with a teaspoon of Dawn dishwashing liquid. Mix in a spray bottle and shake the cleaning solution vigourously then spray the fabric until fully wetted. Use a soft brush to scrub the material. Let sit for 5 minutes then get it wet with clean water. Use a microfiber cloth to soak up the solution then vacuum up the residue with a wet/dry shop vac. Let it dry overnight.

For the leather I give it a good clean with Gliptone cleaner and then treat it with leather conditioner. Every couple of days I treat it until the leather is supple again. Once it's soft I clean it again then do a colour touchup with a airbrush where needed. Final stage is another treatment of conditioner after a few weeks when the colour is fully dried. Seats look like new.