551 A race oddity

Post by **swoakes** » Fri May 18, 2018 8:19 pm

Nice one Ben. Car should go really well with that power and room for more after you get some track time.

Where and when is it's first planned track run

Post by **philhoward** » Fri May 18, 2018 9:15 pm

Nice torque spread there - should make it easy to drive. As you said earlier, the numbers are for pub talk and handicap figures. Looks pretty well mapped (as you’d expect).

Post by **BigBobPilot** » Fri May 18, 2018 9:29 pm

swoakes wrote: ↑
Fri May 18, 2018 8:19 pm
Where and when is it's first planned track run

Silverstone 5th May, but I missed that...

Lets say TBC, but now the car runs & drives, I need to get the bits of body bolted on and get it out there as soon as I can.

Post by **MikeyBikey** » Sat May 19, 2018 9:15 am

Great effort ben.

Post by **turbster** » Sat May 19, 2018 8:59 pm

Looking good Ben!!

Post by **BigBobPilot** » Tue May 22, 2018 10:04 pm

The SS1 has been fuel tight at the rear since I put fuel in the tank. When I got it back from the rolling road, there was a little drip under the pumps / pump pre-filters. I nipped up a jubilee clip. Yesterday, I went in the garage & there was a smell of petrol, there was a small fuel patch under the back. I swapped one jubilee clip and tightened everything else.

I thought I'd check this evening, still a smell, still a little patch of fuel on the ground:

: 20180522_203304[1].jpg (117.04 KiB) Viewed 1306 times

The tail adapter on the lift pump pre-filter outlet (top filter) had just bottomed out before sealing on the taper. Wrapping more PTFE tape round didn't help, so I swapped it for another tail with a longer thread section. However, the fuel weeping through there had got into the end of the rubber pipe, where it's not supposed to see fuel, so that was a bit knackered. I haven't got a piece of fuel pipe the right size, so I temporarily put a piece of coolant pipe on to check I'd found the issue & stopped the leak. It seems to be ok now, but I'll check tomorrow. I'll get a piece of fuel pipe swapped on by the weekend.

Post by **BigBobPilot** » Wed May 23, 2018 7:35 pm

No fuel smell, no petrol patch or wet pipes, so I just need to swap in the section of fuel pipe.

fightingtorque · Post by **fightingtorque** » Thu May 24, 2018 9:05 am

Don't leave it any length of time with a non-petrol hose on it. I used a piece of breather hose as a temporary fit test on a motorcycle system, fitted it on a Friday, nothing left but a strong smell of petrol and a stain on the floor by Monday morning, whole tank had emptied itself, and luckily had evaporated away without major harm. Fuel will destroy certain materials in no time at all.

Post by **BigBobPilot** » Sun May 27, 2018 10:18 pm

The pipe was a very temporary fix, just to stem the leak. The short pipe is now replaced with fuel pipe.

Post by **BigBobPilot** » Sun May 27, 2018 10:47 pm

In place of the original brake servo, I have an adapter for dual master cylinders, as just about seen in the old photo below.

: 20170501_193539.jpg (181.31 KiB) Viewed 1165 times

The front brakes were holding on slightly and the pedal was rock solid. I suspected the the m/c push rod was slightly too long, I couldn't adjust it any further. Slackening off the m/c nuts pushed the m/c forward and let off the front brakes. I've chopped about 6-8mm off both the front & rear rods then bolted it back together, no front brake binding (the rears were ok anyway) and the pedal has some normal movement rather than being solid. I suspect this is why it was so difficult to get fluid through the m/c's when I was bleeding the brakes, the cylinder just wasn't returning to the end & opening to the reservoir.

Post by **BigBobPilot** » Mon May 28, 2018 10:56 pm

I’ve got a bit more done, always less than I’d like to get done though!

I started off thinking I’d just mat in some chop strand around the edges of my bonnet. Where I’d single skined it, I left a little bit around the edges to help stiffen it, matting across from this to the upper skin should stiffen it up a little more for very little weight increase & seal in the remaining little bit of foam. This quickly moved to matting in the louvre & cutting and fitting the NACA duct.

After cuting a hole for the NACA duct, it was tagged in place to mat in underneath.

: 20180527_152006.jpg (112.7 KiB) Viewed 1102 times

With that lot matted underneath, the NACA duct needed attention from the top too, along with some other minor repairs

: 20180527_173647.jpg (124.37 KiB) Viewed 1102 times

After some sanding filling, repeat, etc. it’s primed and lacquered (to be vinyl wrapped)

: 20180528_170225.jpg (145.8 KiB) Viewed 1102 times

The bottom needs painting to seal it from water, but is all joined up and the whole thing does appear to be stiffer

: 20180528_182913.jpg (152.48 KiB) Viewed 1102 times

Here it is on the car

: 20180528_184713.jpg (165.13 KiB) Viewed 1102 times

The big hole is the intercooler outlet, the louvres are turbo outlets (I'll paint this in high temp paint for a little protection, with some heat wrap on the underside), the NACA duct is cooling air in for the turbo, a little ducting will be required around the turbo, but it's to try to keep underbonnet temps down.

Post by **BigBobPilot** » Mon May 28, 2018 10:59 pm

While messing around with the bonnet, I flatted back the previous previously applied primer on the rear wings & had another go, these are now lacquered too and I need to look at why the inner arch was fouling the spring dampers, I have a feeling a little more modification is required.

: 20180528_170236.jpg (167.08 KiB) Viewed 1101 times

Post by **BigBobPilot** » Mon May 28, 2018 11:35 pm

In between sorting the bonnet & rear wings, I’ve flatted back my front ait damn mould a bit more, so it’s just about ready to start waxing up to take a mould. It’s taken quite a bit of effort to salvage that from my impatience!

I have some significant gaping holes in the car. I cut away the complete passenger side floor, to make way for the exhaust. I have reinstated the bulkhead, but a floor is required to separate the exhaust from the cabin, so I’ve made a simple lightweight frame over the exhaust. The heat shield will fit underneath the frame, something like below.

: 20180528_144751.jpg (159.06 KiB) Viewed 1095 times

A few tags need welding on to attach the heat shield and I need to provide some heat shielding for the wiring & battery along the transmission tunnel, but the basic part is in place.

This will then also support the floor, so that when someone (me?) inevitably leans on it, it doesn’t collapse. I’m possibly still going to use the inner skin from the boot lid, although, it may yet be simpler & lighter to make up something to fit the space, rather than trying to modify this:

: 20180528_144825.jpg (134.5 KiB) Viewed 1095 times

A bit of boxing in around the tailpipe is required, there's more to come with the door mods here, so that the exhaust gasses are not drawn in to the cabin. However, this new exhaust tunnel / double floor (there will be a flat floor across the bottom of the chassis rails) will be open to the back of the car, so air flow from the coolant radiator will hopefully been drawn through by the low pressure at the back of the car & also help cool everything - except me in the drivers seat! This is similar to waht we did on Big Bob, although the heat shield was added in after the first run, where burn marks appeared on the floor...

How many extra horsepower can you get by emulating Fred Flintsone? Let’s try:

: 20180528_184529.jpg (209.46 KiB) Viewed 1095 times

The drivers side foot well has been half attached for ages, I’ve just not got around to sorting it. When I’ve tried the brake & throttle pedals, one of the ridges in the original floor is just in the wrong place to allow a smooth transition between the pedals, I kept catching my heel on it. This along with wanting to flat floor the car underside, has made me decide to chop out the original floor. Rather than try to get it fitting back around the edges, where it had been cut by a previous owner, I’ve started again. However, I’m going to put a steel section in to give my feet more protection. This car will eventually be running quite low and I fancy affording my feet a little more protection. It’s a bit more weight , but it’s low down and there for a reason. I started my new steel panel, but it will take a little more sorting yet. This is also a similar solution to Bib Bob, which was also flat floored.

Post by **reliant-reviver** » Tue May 29, 2018 8:02 am

Should have left us to guess on the origin of the donor fibreglass, I didn't see it as "bootlid" till you said it.

Cracking work as ever. Just be nice that it is well on its way to being back together.

Out of interest where did you source your vinyl from? Eldest bro has nearly finished wrapping his new car bit I was surprised by how much the vinyl cost and he said it was difficult to source from companies as a private individual. Might just be fancy vinyl though.

Post by **turbster** » Tue May 29, 2018 8:42 am

reliant-reviver wrote: ↑
Tue May 29, 2018 8:02 am
Should have left us to guess on the origin of the donor fibreglass, I didn't see it as "bootlid" till you said it.

Cracking work as ever. Just be nice that it is well on its way to being back together.

Out of interest where did you source your vinyl from? Eldest bro has nearly finished wrapping his new car bit I was surprised by how much the vinyl cost and he said it was difficult to source from companies as a private individual. Might just be fancy vinyl though.

I ordered a few samples from www.wrapdirect.com They seem pretty reasonable.