Recently Aquired Dolomite Sprint - Advice Needed !

[Andy Cawley]

I have bought a 1980 Dolomite Sprint nearly 40 years after running a couple in the seventies, I bought this one with the express intention of running it in the VSCC Pomeroy Trophy. http://www.vscc.co.uk/page/events?eventID=909

It looks reasonably clean and sound and standard in appearance but apparently has received a fair amount of modification in the shape of solid nylon bushes in the suspension and front sub frame. It has Spax adjustable shocks all round and uprated springs. The flywheel has been lightened and a competition clutch fitted, work done to the crank and rods etc.
The head has been flowed and ports enlarged as has the standard cast iron exhaust manifold. A TriumphTune TT106 Sprint 292 degree cam shaft is fitted together with appropriate springs and Weber carbs.
It is due a trip to the rolling road as I haven't a clue about modern carb set up as my main interest lies in my 1925 Frazer Nash.

My first plea for help is can anybody tell me what diameter the standard steering wheel should be. Funny question I know but a very small wheel has been fitted and the steering is tonnes heavier than I remember (OK so I'm tonnes older I know!!!! ) thus making the car unpleasant to drive on the road. ( Its fine at speed) but I would like to change it.

Secondly a more general question; any particular advice about my set up, is there anything in particular that I should be watching for.

[Toledo Man]

Welcome to the forum. It sounds like you have a sound base with a few mods already in place. Something you should seriously consider is the "trackerjack" brake upgrade (named after the forum user who developed it) which consists of Ford Sierra calipers and VW Golf brake discs. The TDC isn't an MSA member so you will need to sort out the paperwork yourself or do it through another club that is a member of MSA. One of my Club Triumph friends is knowledgable about MSA requirements if you need any help in getting your Sprint compliant.

[Galileo]

Outer diameter of my Sprint steering wheel is 365mm.

[Galileo]

Sorry, where are my manners? Yes indeed, welcome!

[Andy Cawley]

Thanks for the steering wheel info.
I already have a competition licence so am familiar with MSA requirements but thanks for the suggestion.
With a 10.7:1 compression ratio and the cam I have fitted any ideas what sort of bhp I should expect?

[Galileo]

A good question, and one that I suspect no one can tell you exactly what to expect by the nature of everyone being different.

You're starting off with an engine that was designed to be 135bhp, only reliably achieved in practice 127bhp but yet managed 150bhp in testing with a hand built engine. According to Piper, their 296° cam gives an additional 12bhp, so guess yours would be nearer the 10bhp.

Their are others on this forum, being your actual living legends, who can give you far more useful real world track gained knowledge than I can only dream to know one day. Off the top of my head there is Mad Mart, Trackerjack, and then there is Ken Wood who appears to have spent his entire life driving sideways for a start!

May I suggest that you post a separate question with a suitable subject line, like "Racing Sprint, BHP advice" or something of the ilk to get their attention?

[Toledo Man]

I've just measured mine and it is the same. I thought Sprint steering wheels were slightly smaller. They're listed in the post-76 parts catalogue under a different part number (TKC1584).

[barry55]

Hello and welcome,the works rally cars were all between 200-220bhp but you can get around 150 without causing to many other problems such as breaking halfshafts.
Good luck and keep us informed.

[gmsclassics]

Hi and welcome. I expect you will remember a lot, even from the seventies, about the Dolomite's quirks.

Just a few comments in no particular order:
• Don't lower the suspension much more than an inch all round or you adversely affect the rear roll centre.
• LSD is pretty essential. For serious racing fit thicker half shafts and/or additional bearing half way along each shaft. Or replace the entire axle with a Capri one.
• front springs need to be double the pounds of rear. 500/550 front, 225/250 lb rear is a good start
• Centre release bearing for clutch is better than standard system
• Std rear drums with race linings are okay but fronts require upgrading depending on what your regulations will allow. I can substitute with alternative pre78 setups only. Vented rotors, bigger pads of the best possible material are essential to increase your braking capacity or you'll get outbraked into corners.
• Nylon bushes sound very hard, I just use the hardest poly bushes that are available.
• 'Quick rack' with less than std 3.75 turns.
• Cooling will be a problem if you are going to make this car perform. Porsche 944 turbo alloy radiator fits and has similar connections. More air vents where no plate usually is. Good thermostatically controlled fan. If you have to stick to standard radiator, get it remade as good as modern technology will allow and make sure with flaps that all air goes through and can't escape. Oil cooler too.
• Accurate and easy to read gauges, temp and pressure for both water and oil, easy read rev counter with blue strobe change light. I also run a big yellow light to indicate when overdrive is on (so I don't make a mistake under pressure)
• adjustable front drag struts and rear tie bars to give sufficient adjustment when doing alignment. Starter for 10 - caster 4.0, camber -3.2, toe 0.0.

I would wait until you've done the rolling road before even thinking about any changes to the motor as a good operator will get the best out of what you have and point you in the best direction for any further gains. I find the Sprint drives well with good torque, being fast off the start line and out of corners often gains the most places.

Hope this helps

Geoff
93 race meetings in the brown Dolly, and counting!

[Galileo]

I've just measured mine and it is the same. I thought Sprint steering wheels were slightly smaller. They're listed in the post-76 parts catalogue under a different part number (TKC1584).

My parts catalog (1975) says 'Germany' for the TKC1584, and 313149 otherwise, which is the same part number as the 1973 on stag? I'm yet to understand the Triumph part numbering scheme I must admit, such as the occasional 'TKC' prefix, give me the VW one anytime!

[Carledo]

I've just measured mine and it is the same. I thought Sprint steering wheels were slightly smaller. They're listed in the post-76 parts catalogue under a different part number (TKC1584).

My parts catalog (1975) says 'Germany' for the TKC1584, and 313149 otherwise, which is the same part number as the 1973 on stag? I'm yet to understand the Triumph part numbering scheme I must admit, such as the occasional 'TKC' prefix, give me the VW one anytime!

Triumph part numbering is only confusing if you don't understand the "why" of it! Standard/Triumph part numbers were all in the 6 figure format, when Triumph joined BL, new parts got Austin/Morris style part numbers (3 letters and 3 or 4 numbers) but with the first letter being T (for Triumph) rather than A (Austin/Morris/ MG/Wolseley/Riley) R (Rover) or U (universal) If and when early numbered parts were superceded they ALWAYS got later style numbers in the process but no attempt was made to change all numbers to conform, so even on Sprints and TR7s that were all made after the amalgamation, S/T style part numbers still abound.

Steve

I used to love the old Ford part numbering system where you could work out what the part number was, just by knowing which part you wanted and for which model. Every part had a unique number, ie a brake disc was always 1002 so if you wanted a brake disc for a 79 Mustang, the part number you wanted was D9ZZ 1002A, which translates:- D9= 1979, ZZ= Mustang, 1002= Brake rotor and the A is first issue, later mods in the same year got B or later suffix which is the only bit you can't work out. English Fords didn't carry a year code in the part number but had a more precise model code instead, ie 3004E 3304A being a centre steering draglink (3304) for a 2000E Corsair (3004E)
Then they went to the 8 or 9 digit "finis code" numbering system and the numbers mean nothing at all! That's progress!

[Galileo]

That is really useful Steve, one of those things I've wondered about but never bothered to ask things. That change to the numbering scheme is actually a really handy way then to know what is original Standard Triumph.

Sorry for digressing on your thread Andy!

[Andy Cawley]

Well!! I did it.
Drove all the way from home near Bawtry to Silverstone, got through scrutineering, completed high speed wiggle-wogle, high speed garage test, straight (nearly) line sprint and 40 minutes high speed trial and drove all the way back home and it is still going like a good 'un.
The trickey bit was the huge pressure needed on the brake pedal owing to servo failure on Wednesday and no replacement available from Rimmers til the end of the month.
Trip to the rolling road was rewarding, 156 bhp at 6100 rpm.
Fitting Michelin TB15 tyres was the best thing however as the track was damp/wet, these tyres, the rally tyres of the 70s, were fantastic.
I was highly delighted with my result, I came 31 out of 65 starters but even more important 2nd out of the four entrants from our pub. Sadly I was beaten by my son in his £1000 4litre Lexus.
Roll cage and slippy diff now on the shopping list. Any one out there got either one they don't need ?