Something funny...[Nitro Funny Car build thread]

Chevyonfuel

It seems to have been a layering issue. Ordinarily the blacking agent should go on quite easily and work immeditely. In this instance, it took some extra work, and scotchbrite on the areas where it hadn't taken at all.

The only fundamental difference between this chassis and the previous one that had been blacked, was that back during their original construction, the other one was coated in transmission oil to protect it, and mine wasn't as it went straight off for paint. Whether the subsequent media blasting made a difference is unclear, but it's looking like it should now .

Chevyonfuel

A few quick snaps from this morning. The roll cage still needs treating but requires new side bars to be welded in hence the delay on that. Once the front A-arms are treated it's time to crack on with final assembly of the rolling chassis. Following that will be modifications to the fuel tank to get it to fit under the nose of the body.

Back to the chemical blacking though, looks swish - job's a good'un:

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                       

Chevyonfuel

It'll be a couple of weeks before there's a chunk of stuff to provide an update on, but one development recently that'll become a thing in due course, was the exhaust headers. A while ago I waffled on about the downforce effect they provide - in the NHRA it's been a bone of contention for a while and teams were bringing several sets of headers to an event with varying angles of dangle to adjust the car for different track conditions.

                                                                                                                                                 

The fundamentals of it centre around the angle which the headers point, and their effect on how they push the car, be it down or forwards. The development a few years ago was that if you had a decent track, you could lay the headers down so they sweep back rather than up. This coupled with the amount of force they provide (about 800lbs of thrust per pipe - so a fair bit) pushes the car down the track as well as providing some downforce.

If you downsize those numbers based on output, we're looking at around 240lbs of thrust per pipe on the Vette - enough to make a difference still.

The NHRA have mandated a maximum angle, to peg it back a bit, because A) the cars were going quite fast (having said that, Robert Hight still went 339mph last night) and B) When the car dropped a cylinder or started to move around, the reduction in downforce made the cars quite hard to steer.

Because Nostalgia Funny Cars in the UK aren't goverened by the NHRA, and in the interests of fun, the Corvette headers will be leant over a fair away to help the ET. If it gets a bit sketchy and sideways, I'll just have to muddle my way through .

More piccies in a few weeks; should have a rolling chassis and engine in place ready for final assembly soon.

mavrik64

Keep the updates coming, always a good read - thank you

Chevyonfuel

Wheels!
The front end has been an issue for a while; a change of front wheels necessitated a change of spindles. The original spindles were from the crossover period of 2009/2010 when Strange Engineering swapped from Anglia to Strange bearings and different bore spindle shafts.

To cut a long story sideways, the wheels were for Anglia bearings, but the spindles were for the later Strange bearings. A set of older spindles were sourced, and after much refurbishment and tweaking, they were bolted on today for a trial fit.

                                                                                                                                                 

                                                                                                                                                 

They fit, they spin and they turn; I'll take that at this point - some final tweaks and adjustments for the steering linkage brackets and the front end should be ready for final assembly.

                                                                                                                                                 

Tinwork - anodized with the addition of gold dye. It's not really my thing, so this assortment of panels, covers, boxes and the seat, will be off for re-anodizing shortly. Initially the plan was for black - safe and a bit ordinary. So depending on what's available, a dark green might be in order. Time will tell on that. The hound was confused by all the gold stuff being hosed down outside...

Another update in a week or two hopefully. The rear gears for the diff will be swapped over; one of the more monster spec parts of the car .

Chevyonfuel

A quick trip to the workshop yesterday afternoon to drop off the new rear-end gears. This turned into a nightmare, but more on that later.

                                                                                                                                                 

                                                                                                                                                 

The front wheels mentioned in the last update, now have their steering linkage all in, and the motor plate has receieved the same chemical blacking to tidy that up. I'm a bit closer to getting the tin work anodised, possibly in the next couple of weeks. Things should pick up pace once the rear end is back in the car and the seat's back in.

Speaking of the rear end - it's a famous unit, it was used in Joe Amato's Top Fuel dragster many moons ago. That's a double edged sword however - as a 9.5" gear toploader case, they actually used 9" Ford pro gears, not 9.5" (which is what you'd order today if you needed one). You can see where this is going...

So we have a diff gear that's too big for the casing and the casing cannot be machined to receive a larger gear. It's not the end of the world, but for now the gear set in the axle will stay there and it'll be changed out next year once we have some test laps under our belt.

Some more piccies in a few weeks once the anodising is all done...

Chevyonfuel

Gears!
Going back to my last post, the conundrum of having a 9.5" gear and a 9.0" case has been resolved - where there's a will, there's a way. It's been common practice to take material of ring gears to suit a smaller case, for some time. With the excess of material on the ring gear in this case, taking an 1/8" off isn't an issue as you still aren't into the teeth afterwards.

With that in mind, the ring gear is at a machine shop having the necessary done at the moment. In other news, the car's back on the floor in a rolling state in the meantime. The next bit of work is to fabricate the new steering column...

After moving and rotating the seat, my knees are now in a raised position that fouled on the previous steering column. The new one needs to sit a little higher, and might end up having an additional pair of bars leading back to the front hoop of the roll cage to encase the test monkey a bit better.

I'll hopefully have a more detailed update on this at the weekend . In other news, I'm sorting out the last of the tools that are needed for the more bespoke jobs (little things like clutch stand adjusters, stud installers / removers etc). You can spend a fortune on useless tools you'll never use, but having the right stuff available helps get the car serviced so quickly between rounds.

Speaking of which, a quite fun video from the US, showing how quickly a big show Funny Car can be stripped down, if you're in a hurry...
                               
With the exception of a bigger supercharger and the down nozzles you see plumbed into the heads, for the most parts it's identical kit. Far easier to work on than Chevy and Ford stuff .

Chevyonfuel

Today was spent doing things we hadn't expected to...
So, initially the intention was to fabricate the new steering crossover. Due to some staffing issues (everyone who's normally at the workshop on Saturdays were on holiday), the two of us were left to rearrange everything just to get the workshop in a go state - having the workshop split between a build and a base of operation for racing the big show car, means lots of moving of cars.

With my chassis now back rolling, it made sense to roll it outside in the sunshine. It looks quite tidy, clean and no nonsense. It'll come together quite quickly once the new steering crossover is in.

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

I mentioned the big show car, to explain this a bit further - since it's a nice bit of kit and quite a monster...

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

It uses a chassis similar to my car, but running on 36" tyres, with a 3.20:1 rear gear, direct drive and a 500 cubic inch engine. With a 14/71 blower and near 100 gallon per minute fuel pump, it makes something in the region of 8000 horsepower. Sufficient to hit 280mph in around 4.4 seconds. This is where Funny Cars ended up, it's a different discipline to the 70's equivalent. One day I'll hopefully license in the car - you only live once .

Hopefully another update next weekend.

Chevyonfuel

An update from today... some good progress in a few areas.

Firstly, the cockpit - as mentioned a while back, the changes to the seat area meant that my driving position is altered, moving my knees up into where the steering crossover should be. The fix was to build a new one, but given how my knees are above the top chassis rail, some design flair was needed to make it do two jobs.

                                                                                                                                                 

Elsewhere, the motor is now in the chassis, for mock-up purposes at this stage to confirm what forward visibility is like in the car. I'm used to not seeing much from the driver's seat, so this didn't come as a shock as being that low in the car, you're unlikely to be able to see over the injector.

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

Next up, finishing off the steering box mount (you can see the bracket below the steering crossover, this is where the steering box, column and wheel hang from), then side bars in the cage and the wheelie bar construction.

One tube needs to be slightly moved to allow the oil pump to fully clearance the chassis uprights - this is byproduct of the engine change. The previous engine ran a tri-drive meaning the oil pump was out in front rather than dangling out the side of the block.

All in all, good stuff - we're starting to motor on through the list of jobs

Chevyonfuel

Stuff that happened this week...

                                                                                                                                                 

An assortment of nuts, bolts and washers arrived from the US, along with what are called burn down windows. The bolts are aircraft grade and used to attach the rear axle in its mounting plates at the back of the chassis. You wouldn't want to use standard hardware and have it fall out.

The burn down windows sit in the firewall and allow the driver a view at the bottom end of the engine in the event of a fire - ordinarily a fire will manifest as a rod exiting the block and engine oil and fuel getting on the headers, catching light and producing that bright orange and yellow colour associated with a bonfire - the windows (plexiglass) just clue you in that all is not well, should it not be obvious from an oil pressure drop.

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

The roll cage is now finished in terms of new bars, an adjusted titanium head shield, and subsequent chemical blacking. The side bars in the cage serve a second purpose in being the mounting point for the head pads that are the norm in modern Funny Cars these days (will be mounted shortly).

Next up will be the oil catch can that'll be mounted behind the cage, then the wheelie bar, and that'll complete the chassis fabrication bar for a few bars, tabs and brackets here and there.