Wednesday, 3 April 2019

2019 1st April, New Sprint Engine saga - No Joke

Having decided to build up the original Sprint engine I first started work on in 2014 I began by cleaning up and checking over the block.
"New" block I started in 2014
Cleaned up ready to start work
Checking threads are OK
Bottom end ready for -
the balanced crankshaft
and a set of pistons on balanced rods
Choose your jackshaft
Starting to look like an engine, until -
Curses, pistons are well above the block face
Having made what I thought was good progress with the bottom end of the engine it all came to a sudden stop when I realised the pistons were about 0.025" above the block face at TDC.  This might be OK for a race engine when it is used as a way of getting more compression ratio but I didn't want or need it for a road car.  I discussed the options with Alex at Maynard Engines and we decided it would be possible to machine a small amount off the top of the pistons, so I stripped them back out and took them down to him for machining.
Pistons showing amounts to be machined off.
I also took the head from rally engine head down to be checked for flatness.  The exhaust manifold that came with the engine was also slightly warped where it bolts to the head so that needed to be machined flat as well. 

2019, Daffodil Run

Daffodil Run

Our first trip out in 2019 was the Daffodil Run at the end of March. This is quite local to us and is based on the Gloucestershire/Herefordshire border.  The weather was fairly cold so the FHC was the obvious choice.
Jo standing by our ride at the start.
The 80 mile run started and finished at Hillside Brewery near Longhope and about 50 cars were taking part.
Our route took us out through daffodil lined country lanes to a stop for coffee and cake near Newent.

After the coffee break we followed the River Wye via a quaint little place called Hole in the Wall and back to a nice meal in the brewery cafe.  Lovely day out and the car behaved itself nicely.

2018-2019 Winter Jobs 2. Sprint Engine - Problems

I had found a Sprint engine that had been used in a TR7 rally car and bought it for a "reasonable" price so the plan was to give it a quick check it over and fit the engine in the FHC over the winter.
TR7 Sprint Rally Engine
It was running on 45DCOE carbs with a fast road cam etc etc so should be good for about 160-170bhp. Naturally there were a few things I wanted to check and it turned out to be a bit more work than expected.
First thing I noticed was the cam sprocket support bracket was missing. This holds the sprocket in place and allows you to work on the cam without taking the chain off,  like when you need to alter the tappet shims. Not a good sign.
There should be a guide pin in the middle of that sprocket!
Next thing I spotted was that one of the 14 bolts holding the rocker gear to the head was metric. Just one, but it should have been UNC thread!  Why would you put one odd bolt in?

Metric bolt, that should not be in this engine!
Another bad sign, so I now knew whoever built it was either in a big hurry or they didn't know what they were doing.
Either way it prompted me to completely strip the engine to see if I could find any more things to worry about and I soon noticed there was way too much end float on the crankshaft.  I found it because there was a loud "clonk" when I turned the engine upside down on the stand as the weight of the crank assembly made it to slide sideways in the main bearings . It should have been between 0.003"-0.011" but it was more like 0.020". This meant incorrect size thrust washers were used.

At this point I decided it would be best to "park" this engine for the time being and go back to the one I had started to build back in 2014. The quick swap job was back to being a big build after all.

Friday, 15 March 2019

2018-19. Winter Jobs 1

Lots of little (and large) jobs to do on the FHC to get it ready for some classic runs coming up quite soon.
First job was to sort out a misfire that has got worse recently, especially above 3500-4000rpm.  I was thinking it was a fuel issue but thought it was worth checking the other basics like ignition. Poking around the engine I noticed the points gap looked too small so thought it was worth adjusting them, but I had forgotten how much of a pain that is on a standard TR7 with the AC Delco distributor.  Having got the points set up better (or so I thought) I found the misfire was now much worse, despite checking the timing was spot, on so I decided to bite the bullet and fit the Lumenition set that was on the shelf.  I also had a spare Delco distributor already made up with the Lumenition inside.

This was when I discovered the distributor was held in by the wrong bolts.  All the bolts in the TR7 engine are UNF unless they are into aluminium in which case they are UNC. As you can see from the picture some idiot had used the wong ones.
Correct UNF bolt on the left, wong UNC bolt on the right.
 Luckily new UNF bolts went in OK and I was able to put it all back together OK.  Setting the timing with the strobe light was easy because I now had rock steady timing marks in the beam instead of the old wandering ones.    

Wednesday, 13 March 2019

2019 Calendar. Busy Year

2019 is shaping up to be a busy year.  We have ten classic runs so far with another couple of possibles and a couple of shows thrown in. The calendar so far looks like this:-

23rd March,  Daffodil Run
7th April,  Taith Cymru
14th April,  Corinium Run
28th April,  Drive It Day
5th May,  Wheelnuts Classic Car Show
11th May,  Bluebell Run
19th May,  Hills & Valley Tour
30th June,  Black Mountains Classic Tour
7th July, Aquae Sulis Classic Tour
3rd August, Gloucestershire Extravaganza, South Cerney
4th August,  Valleys & Villages Classic Tour
1st September,  Cotswold Classic Run
19th-20th October,  Lombard Rally Bath

Sunday, 30 December 2018

2018, October 19-20th Lombard Rally Bath

The entry list for the Lombard Rally Bath 2018 looked a bit like a Who's Who of British rallying with illustrious names like Stig Blomquist, Jimmy McRae, Dai Llewellyn, Louise Aitken-Walker, Graham Elsmore etc etc etc. They were driving such classic cars as Audi Quattro, Opel Manta 400, Lancia 037, Alpine Renault 110, Datsun 240Z, Ford Escort Mk. 1&2 and Mini Cooper S to name but a few.   My navigator was my old school friend Oliver Tomlins who I have competed on rallies with since we both discovered cars in the late 1960s.  We had been allocated start number 118 being a relatively modern and standard TR7.  There were four other TR7s doing it as well, all proper TR7V8 rally cars.
Cars were flagged away from the start in Pultney Street in Bath just like back in the 1970s. Lots of people had gathered to watch us which gave the event a nice friendly send off.

The idea of the event was to revisit some of the classic stages used on the 1976 Lombard RAC Rally so our first location to visit was Longleat Safari Park but it was bit foggy here so we couldn't see much!
Longleat House is there in the mist somewhere behind us.

The day brightened up - literally - as we headed down to our next destination at Cricket St Thomas in lovely sunshine with lots of people watching along the route.  Apart from being used on several events this is also best known for being the house in the TV programme "To The Manor Born" and being the Crinkley Bottom house in Noel Edmonds TV show "Noel's House Party".

We were given coffee and biscuits here before a go along the stage.
Selection of cars at Cricket St Thomas
Cricket St Thomas
From Cricket St Thomas the route took us south to the Wiscombe Park Hillclimb course which is close to the coast near Salcombe.  This location was fully marshalled and officially open to paying spectators. We even had a number of the local Police force directing traffic for us.

We had never been to Wiscombe Park before so it was all new to us. The marshalls at the start warned us that several cars had spun at the first corner in front of hundreds of spectators so best to take care on that one.  It was also nice to meet couple of our friends who popped up here, Tim Best (who took the photo below) and Chris Riley who has so often helped me with building my cars.
Start line Wiscombe Park
The hillclimb turned out to be narrow and quite tricky with a slippery hairpin under trees but we attacked it and enjoyed the run, even managing not to spin.
Wiscombe finish line
After Wiscombe there was a longish run from the south coast all the way up to the north coast at Minehead for lunch in the Beach Hotel. There were hundreds of spectators here taking the chance to look at the parked rally cars whilst the crews had something to eat.

Our next destination was the Porlock Toll Road. This is a privately owned road so is not subject to the normal speed limits and is still used on lots of events. Oliver had watched in car videos and used OS maps to make some basic pacenotes for Porlock so we could attack it with a good deal of confidence and we really enjoyed it.  The lower section is twisty under trees but it opens out across moorland nearer the top so is quite fast.
Nearing the top of the Porlock Toll Road.
I was very pleased with how the TR7 handled here as it was the first chance to drive it that hard. Braking and suspension settings were good and the handling inspired confidence. Just needs some more power now so that new Sprint engine cannot come too soon!
One little bit of trivia from Porlock was ex British rally champion who managed to take a front wing off his borrowed Opel Manta 400 on the hairpin.
Ooops! Jimmy McRae loses his wing on Porlock.

From Porlock we had an interesting run across country and via Cheddar Gorge to the finish back in Bath where the organisers gave us a super dinner at the Macdonald Bath Spa Hotel.  During the meal the various celebrity drivers were interviewed and entertained up with anecdotes from their rally history. Some very funny and some scandalous stories were told!

Arriving home next day we had covered about 350 miles so that is a pretty good first test run I think.

Friday, 28 December 2018

October 2018, FHC Final preparations for Lombard Rally Bath

The car was more or less ready to go for the Lombard Rally Bath 2018 on 19th-20th October but I did need to get the tyres replaced as the ones on the wheels were the wrong size and too old anyway.  I run 14" wheels and it turns out that the size I need - 195/60x14 - are not as common nowadays as they used to be. This size has the benefit of being exactly the same rolling diameter as the standard TR7 tyres of 185/70x13.  Budget brands were more common but some searching around found some better quality Firestone Firehawk TZ200 at a local supplier.  These seem to be a good result and feel nice on the car with low noise and decent grip levels.
One of the last jobs was to change the standard sealed beam headlights on the car to some more modern Lucas halogen H4 replacements.  Imagine my surprise when I took the rubber surrounds off the headlights and found all new mountings! My previous TR7 experience has been with nasty rusty ones.
Wow, all new. Never seen that on a TR7 before.
The car was now running, but not very well. The carb mounting rubbers did not look very nice with the usual cracks starting to appear so I swapped them for some better ones which improved things but not enough. I booked a quick session on my local rolling road at Maynard Engines where Martin spent a short time setting the carbs up properly and got it ticking over like a sewing machine. 
Car washed and ready for the Lombard.