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

Chevyonfuel

In most cases it's because they aren't DoT approved in the US. They're strong enough (these are forged and pass SFI 15.1 tech), but I guess the manufacturer doesn't want to hassle of all that. They'd end up having to add more strength and therefore weight, and us racers like our pizza so lightweight parts are always welcome .

The main issue I'd expect, certainly with Funny Cars and dragsters is the mounts are spindles rather than studs, so it's only held on by a split pin. I'll try and get some piccies of the spindles when I'm at the workshop next weekend.

outoftheknow

Thanks and I suspect the attachment is as much of the issue as anything else as well. Single securing though on the road (single nut) is permitted - certainly was in the  old days of Jags with wire basket wheels and central nuts IIRC.

Anyway back on topic and looking forward to the next instalment

Chevyonfuel

Carrying on from where I left off; some more hardware has been sorted, which helps things along a little.

                                                                                                                                                  

The spare short block which is in race ready condition, has been prepped for shipping. This is identical to the first engine with the exception of the bearing sizes. Currently the crank is a std/std grind, whereas the first engine has a 10/10 grind. Long term the plan would be to get the crank ground 10 thou and keep the whole inventory the same. A spare pair of heads (BAE fuel heads as per the other engine) are being sorted at present. The plan is to get a full 2nd motor built up with a more punchy fuel system to get the car running where I’d like it once the ‘probation’ season is under the belt. My intention is just to get laps on the car this year and iron out the bugs, before stepping it up at all.
  
Elsewhere, the data acquisition has been taken care of with a Racepak PRO-1A.

                                                                                                                                                  

This is an older generation datalogger (I say older…it would run Windows 95!). The ability to see what happens on a run throughout the car is invaluable, as reading bearings and spark plugs, whilst vital doesn’t tell the whole story. The Racepak sensors will measure:

Oil pressure
Fuel pressure
Fuel nozzle pressure
Engine RPM
Engine cylinder temperature
Driveshaft RPM
Boost pressure

Onto the body – this is been a challenge / adventure. After lots of running around, it eventually left New York on Thursday. This is rather later than hoped for, but a combination of Christmas & New Year, and then the snow storm recently delayed things a little. I’m glued to the Marine Traffic website to keep updated with where the big lump of a boat is. The body should arrive in the UK between the 7th and 12th of Feb, so it’s almost become an actual thing.

It’s a similar story for the first engine and associated large parts; that’s floating its way here for the end of Feb. The next update will be with a large lump of fibreglass mocked up on a rolling chassis hopefully; then the complicated and fiddly work can begin.

Chevyonfuel

Brace yourself...photos, waffle...get a coffee and read on

On Friday the first crate containing the engine, transmission, spare clutch and some miscellaneous spares arrived. That was a relief, the ship appeared to be passing all those pirate islands - I've seen Captain Phillips, and I knew Tom Hanks couldn't bail me out of trouble.

                                                                                                                                                 

                                                                                                                                                 

The bug catcher injector is currently in my lounge - since it arrived not bolted on, I didn't want to risk it falling off the first time somebody leaned on it...
The frost on the valve covers and manifold is where the salty sea air has had a go at the magnesium. This will clean up and hasn't damaged it (I had a bit of a panic when I first saw it).

Today, some sexy looking fibreglass arrived. It's taken months, but was worth the wait.

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

The elephant in the room was that the roll cage on the car is (now was) too tall. To explain this - the chassis was built to a more modern take on Funny Car construction, with an almost bolt-upright seating position, for clear visibility above the engine.

Back in the 1970's, appearance was of equal importance to performance, therefore the style of roll cage and driver orientation in the car was somewhat different. Drivers sat far more laid back (which coined the term 'layback chassis'. This allowed roll cages to be lower, and bodies to hunker down a little lower.

With the body dropped on top to see how big the elephant in the room was (along with something else I'll come onto in a second), it was obvious we had an issue. A big, 10 inch issue to be precise. I still have to squeeze into the seat, so it wasn't just a case of lopping off the cage - other bits need to change.

The fix, to get the body to sit low enough to cover up part of the back tyre, is to reduce the cage height a bit, along with lowering the seat and adjusting my seating angle (semi-layback style). This should get us as near as practicable to an aesthetic that works. The cage that was cut off, can be saved in part, it's just the front hoop that's likely to have to be re-made.

In addition, the front end of the chassis was protruding beyond the tip of the body. This is an easier fix in some ways, and a pain in others...

                                                                                                                                                 

Cutting off the front to tuck it under the body was easy enough, a loss of 6" is by no means the end of the world. The knock on effect though is having to move the fuel tank back - and with how low the body sits in that area, it's likely we'll have to re-make the tank (it's a bit too tall at present).

                                                                                                                                                 

The next update will be in a few weeks hopefully. I'll be having a proper seat fitment so we can finalise the height of the new cage, and then it's full steam ahead to mount the body, and once the injector opening in the bonnet is cut, I'll be going through the engine before it gets properly installed. Good times

RBZ5416

Great stuff Jon.

Chevyonfuel

Some stuff that isn't car related (safety first, kids). In the early hours of this morning I got the first glimpse of my crash helmet. This had some custom paint, pinstriping & lettering courtesy of my main parts source, Brendan Murry (who also has been compiling the engine hardware - talented bloke).
                                                                                                                                                 

                                                                                                                                                 

Funny Car helmets have quite a lot of stuff going on when you get beyond the mere function of protecting your noggin. HANS posts and a chin strap are fitted, personally I find the HANS to be brilliant - back when we only had the option of a neck brace, I hated the feel of it (plus it tended to leave your head canted backwards in an awkward fashion).

The built in respirators help keep some of the nitro fumes away, and the air line will be piped into the onboard fresh air system to provide much need oxygen in the event of the cockpit being engulfed in flames. Job's a good'un .

RBZ5416

Let's hope you never get to test it...

Chevyonfuel

To bring things up to date, last week saw some good progress, albeit I was on holiday a few days later so couldn’t compile all the photos and type up any of it.

The 14th of March was the SFI tour UK stop. Certain bits of cars and bikes, along with safety kit have a certification sticker. These vary in expiry dates from 1 to 6 years. It’s much like an MoT for specific racing related parts. In this instance, I only had a bellhousing that needed re-tagging. Bearing in mind it last saw service in 1986, I wasn’t sure whether it would easily get a new sticker. No problem at all as it turned out, so job’s a good’un.

With the bellhousing now legal again, it was time to get it mocked up in the chassis now the engine was in. The function of the day was mainly to ensure the drivetrain was in a straight line after all the jiggery-pokery regarding the centreline of the drivetrain. This went better than expected and everything bolted in snuggly – the driveshaft needs a slither of material removed to provide some clearance inside the coupler, but other than that it looks excellent.

                                                                                                                                                 

                                                                                                                                                 

To the most complicated, time consuming part – the cockpit / roll cage / seat…

Going back a few weeks, the roll cage was cut off to make way for a new, lower one to try and get the body to sit better over the rear end. To add more complexity to this, there was going to be a need to lower and rotate my seating position. With the drivetrain now in we could mock up a seat location in terms of height and rotation. After a quick fitting to see what we were dealing with, there was a way forward, which on the face of it doesn’t look as extreme as it might.

I’m trying to avoid having to cut into the body to allow the top vertical hoops of the cage to protrude slightly, as I dislike the looks of it. In terms of the numbers involved, the lowering, cutting, stretching etc has gained us near enough the 10 inches needed to get the body down low on the tyre.

                                                                                                                                                 

                                                                                                                                                 

                                                                                                                                                 

However…more work is required. The steering column arrangement now fouls around my knees – so that needs raising, which isn’t an issue, but the laydown chassis layout created another issue back in period, which still exists now; with the driver stretched out, their legs sit quite high in the cockpit as the pedals need to be raised to duck around the transmission and bellhousing.

                                                                                                                                                 

The solution to add some protection around the legs, will be quite radical, and it might be the only chassis to adopt this type of solution, or it might start a trend; we don’t know, but it’ll certainly create a talking point. Once fabrication has been completed it’ll make more sense in photos, as it’s difficult to explain all the tube placement. I’m due to receive a bundle of parts at the end of the week, so I’ll try and update things after the weekend. In theory all the safety kit should be here so I can a proper seat fitment sorted and the roll cage height can be finalised within in a couple of weeks.

Chevyonfuel

The first batch of hardware / software / misc arrived today.

                                                                                                                                                 

Some of the bits are worth a waffle about, firstly the ignition system, in this case a hopped up points activated magneto. This pumps out 8.3 amps, which when measured in the same fashion as MSD do with their promags, make it almost as potent as a 44amp magneto found on a current big show fuel car. It'll work well with 'just' 21 gallons of fuel to burn per minute .

                                                                                                                                                 

The Racepak computer and the wiring associated with it, is as congested as a poorly thought home cinema install (I'm guilty of having one of those).

                                                                                                                                                 

I mentioned before the channels that it records data for; this was state of the art about a decade ago (if not longer). Things have moved on, but when it comes to data, it's numbers and this was built for blown nitro combinations so job's a good'un.

                                                                                                                                                 

The data is stored on a memory card and then downloaded to a laptop via the Racepak software. Prevention is better than cure, especially in this game, so it's quite common to see teams run the datalogger in a warm-up to get info about fuel flow rates, oil pressure and the like.

Next week the last of the hardware to complete the first engine should arrive, including the blower restraint which is all sorts of straps, bags, clips etc, and a quite swish carbon fibre diaper to handle lower containment issues around the oil pan.

Have a good Easter folks .

RBZ5416

A little OT but just catching a little NHRA action on ESPN. Good to see John Force still racing FC at 66 but was amazed the Chris Karamasines is still running a DSR TF at 84!