The Triumph Dolomite Club - Discussion Forum

DavePoth wrote:....I'd start with renewing the shocks and springs for now. I imagine they're original and they'll be pretty tired.

Good call. Fitting single piston, sliding callipers in place of the original twin pot ones would be a bit of a waste if the thing would simply bounce off the road rather than stop, not that uprated brakes are necessary for road use.

And if I'd come close to provoking deploymerisation with stock Dolly brakes in a total of a shade over 200,000 miles (161k in ACU, 41k in PKE) of daily driving between my two early autos (same calipers as the 1300 uses), then believe me, I'd be the first to say they were an essential upgrade area, but in good condition, with all pistons free and decent pads fitted (I.E. not cheapies with soap and feathers in their makeup), the relatively light Dolomite will stop perfectly well.
I'm sure that Jon's conversion must be great for track work, but then I've not done that with a Dolomite and he has.

Hi Rob,

Sounds like you've similar plans to me, getting more power out of an ohv engine (mine's a 1500 but same principal). I've got a build thread on here called "my 1500hl project". With hindsight I can say it would be far cheaper to put sprint running gear into your car. But it would be pretty dull round here if we all did the same thing!
The trackerjack brake conversion is superb and well worth the money.

JPB wrote:Fitting single piston, sliding callipers in place of the original twin pot ones would be a bit of a waste if the thing would simply bounce off the road rather than stop, not that uprated brakes are necessary for road use.

And if I'd come close to provoking deploymerisation with stock Dolly brakes in a total of a shade over 200,000 miles (161k in ACU, 41k in PKE) of daily driving between my two early autos (same calipers as the 1300 uses), then believe me, I'd be the first to say they were an essential upgrade area, but in good condition, with all pistons free and decent pads fitted (I.E. not cheapies with soap and feathers in their makeup), the relatively light Dolomite will stop perfectly well.
I'm sure that Jon's conversion must be great for track work, but then I've not done that with a Dolomite and he has.

Sorry John, I have to disagree.
Try driving a Dolomite with uprated brakes just once and the cost of the conversion seems cheap indeed.


Four years ago when I considered buying another Dolomite, the availability of improved brakes was a big factor.
Having run a Sprint for ten years on standard brakes I didn't want to go back to the locked wheels in passing places scenario.

JPB wrote:

DavePoth wrote:....I'd start with renewing the shocks and springs for now. I imagine they're original and they'll be pretty tired.

Good call. Fitting single piston, sliding callipers in place of the original twin pot ones would be a bit of a waste if the thing would simply bounce off the road rather than stop, not that uprated brakes are necessary for road use.

And if I'd come close to provoking deploymerisation with stock Dolly brakes in a total of a shade over 200,000 miles (161k in ACU, 41k in PKE) of daily driving between my two early autos (same calipers as the 1300 uses), then believe me, I'd be the first to say they were an essential upgrade area, but in good condition, with all pistons free and decent pads fitted (I.E. not cheapies with soap and feathers in their makeup), the relatively light Dolomite will stop perfectly well.
I'm sure that Jon's conversion must be great for track work, but then I've not done that with a Dolomite and he has.

I think that depends on how you drive on the road.

I know full well that I will end up with glowing brakes on the Sprint...I suspect it's possible to overcome them with 60hp too with a few consecutive hard stops.
It would certainly be in the back of my mind....so I can understand wanting an upgrade, particularly when you consider how much better tyres are than when the car was new.

Twin pot pistons serve no advantage over single pot sliders either. It's just added weight, imbalance and more seals.
I have to admit, I don't understand these 10 pot multi pad calipers...it's the other end of the scale where it's nothing more than for pub talk.

I've completely cooked the brakes of a ford puma and a ford probe so far. The puma isn't much heavier than a dolomite and it has larger, vented disks.

I have had a think about this.
The 1300 tuned to 110bhp+, that makes it more or less a race engine, very high lift cam, massive amount of headwork and so on. Any such engine will need to rev to what, 8000rpm?? so the diff will need to be low enough ratio (ie 4.11) there will not be a great deal of torque at "normal" rpm, so you may not achieve what you want. The other alternative is supercharging, but a whole different kettle of fish. Lots of torque though.

If you want more grunt, the easiest way is simply a bigger engine. Really, it is. Plus MUCH cheaper and will last many time longer. Sounds like a sprint would be a better bet TBH (or an engine swap, I like zetecs!)

Not meant to be a downer, but having had cars with high lift cams (my 1500 toledo has a TH5 cam) I know they are not usually what you expect. You really need to try some out.

ponchoj wrote: I know full well that I will end up with glowing brakes on the Sprint
I've completely cooked the brakes of a ford puma and a ford probe so far. The puma isn't much heavier than a dolomite and it has larger, vented disks.

These two sentences say it all.

Oh and multi pot calipers DO serve a purpose other than a wallet emptying device.

Oli_88 wrote:...multi pot calipers DO serve a purpose other than a wallet emptying device.

Agreed; they look bangin' under a nice set of bling rims, innit.

Sorry, I'll put the Duck tape back over my face now.

Oli_88 wrote:

ponchoj wrote: I know full well that I will end up with glowing brakes on the Sprint
I've completely cooked the brakes of a ford puma and a ford probe so far. The puma isn't much heavier than a dolomite and it has larger, vented disks.

These two sentences say it all.

Oh and multi pot calipers DO serve a purpose other than a wallet emptying device.

It certainly does say it all. Cooked brakes aren't fun and they're easier to get than a lot of people realise.


Multi-piston, ie. 4 and 6 pot calipers certainly do serve a purpose, I agree.
Twelve piston water-cooled titanium finished calipers don't though. All they do is increase unsprung weight and look wikkid.

NASCAR fit their 6 pots under 15" wheels and brake from 180mph to 90mph 4 times a minute - extreme. They still don't cook their brakes and still can lock their wheels at such speeds. You don't need pads that cover half the disk for any application...and as a result you don't need 12 pistons in your calipers....it's for show.

Most racing series have seen the scaling back of brakes, for simplification, reliability and because there's a limit to how much you need.


Tiny solid disks with calipers from a capri are quite simply going to be terrible though. An upgrade is very wise if you want to drive the car with a bit of spirit. I think you'll see from the cooling system thread that I won't modify something unless it warrants it.

Andybrad wrote:Hi Rob,

Sounds like you've similar plans to me, getting more power out of an ohv engine (mine's a 1500 but same principal). I've got a build thread on here called "my 1500hl project". With hindsight I can say it would be far cheaper to put sprint running gear into your car. But it would be pretty dull round here if we all did the same thing!
The trackerjack brake conversion is superb and well worth the money.

Hi Andy

Well... after much thought whilst at work I've come to the conclusion that yes 100HP+ from the dolomite 1300 OHV is possible (from an already "good" running engine) doing the modifications isn't a hard task either but...
Taking into consideration you have "Disturb" an already good running engine to take the modifications might not be such a good thing.. after all obtaining the horse power is easy is with the correct engine that is setup correctly for the use to which it would used eg (normal road driving with the occasionally heavy foot moment).
But its creating a lot more stress on the engine,block and other components for a design that is now over 30 years old! eg suspension components,while this can be upgraded to firmer dampers and shorter springs and so on,you will then have to upgrade the brakes to which then the replacement parts such as pads,discs will cost more.

To acheive 100-120HP wouldn't necesarrily require a "race cam" or anything else that inclines "racing use" But much higher uprated parts that fitted from standard. and well.. that kind of power in such a light car would be fun to some,Come the time when something breaks internally its going to be very expensive!

It would be nice to have my own "personal" mark placed into the car such as tuning etc but.. if your going to attempt to tune a car - perhaps the dolomite isn't such a "great" car to start out with... all you have to do is look back into the pages of history and look how it did in the days of racing. (ok ok, they maybe great setup for a track and so on but.. if money is going to be spent on tuning a car,it has to be a car that has the pedigree to follow.) and the 1300 dosen't have this racing pedigree... and pushing such HP from the 1300 engine(which started out as an 800cc engine many moons ago which over the years has been bored out until we get to this stage of being a 1300 and 1500 engine.. its putting massive amounts of pressure and stress on an already old design to which - such high power will most certainly end the life of the engine much faster than it would if left standard...

So... for these reasons alone... im actually not going to bother with the modifications

1) my taste may not always suit others taste's (which is going to be useless if im ever to sell up)
2) the current engine could easily last another 20 years, if modified that could be shortened to probably less than 5 years! due to the extensive added pressures and stress caused by the modifications
3) it probably isn't worth it... want a fast car with power,buy a bigger engined car,designed to give bigger outputs from standard (as the parts are designed for that particular job already,coping with the higher HP figures etc)
and finally.. "i personally wouldn't like to begin attracting un-wanted attention by any thieving scrote because it looks good,with alloy and looks as if its had money spent on it, as everyone knows classics are easy to steal "don't give anybody any reason to steal a classic!"

Rob

Welll I've seen a lot of noise on this thread, but some good advice from the usual suspects who have spent a lifetime of dolomiting.

A dolomite 1300 is in no way under braked out of the box. A sprint one could say possibly was and will definitely be now if it isnt fitted with the right pads and has one seized piston on each calliper...in which condition it will happily pass the MoT roller test.
Ergo if you wnat to fly about on the road in a Sprint or live in the alps or do a lot of track work, then the trackerjack conversion is the way to go and is one of the first places to spend money on a go faster sprint.

In the case of a young one's 1300 a TJ brake conversion is a waste of time and money no matter what you do to the engine. Ensure all 4 pistons slide freely and fit some decent mintex or ferodo pads on reasonable condition disks and ensure the rear drums are adjusted up well and all will be fine.

Now regarding the diff ratio, 4.11 is a screaming ratio leaving you at over 4 k at motorway cruise.
What you want is a 3.89 or the more common 3.63. Both will transform the car and its quite capable of pulling that unless you do a lot of 4 up work in welsh valleys. I know this to be true cos I've done it to ours....

If you do have a regular quota of lardies on board and you live in a hilly area and never go near a motorway then stick with the 4.11

The ford type 9 box is a great way to go but is dear. Best is to bag an overdrive box if you do a lot of m-way stuff.

Jonners

Just to add ma two penneth.

Standard brakes on a Sprint are up to the job for normal driving, but with a bit of spirited driving with lots of hard braking you will get brake fade, been there a couple of times. I've never driven a 1300 but with similar brakes as the Sprint I think if you are doing a lot of hard braking you could well get brake fade. So if you are thinking about taking it on track then definitely upgrade the front brakes. There are a few different setups out there but you are going to be hard pushed to beat Jon's Sierra/Golf conversion price wise. If you don't intend tracking it, strip/rebuild the calipers with new seals & make sure the pistons move smoothly in the bores and fit better brake pads.

And here's my two penneth worth,

I recently returned my sprint to the road after a long lay up and spent a long time wondering what to do the brakes. I bought my fast road engine from IanDollySprint (currently doing a cracking vauxhall red top conversion) anyway I went out in his car to test the engine and his is fitted with a trackerjack conversion and I must say it was really impressive. However I really did want to see how good the standard set up could be made work with a few tweeks, in the long term I may well go over the trakerjack brakes but I had that itch to see what could be done. So here's what I did;
Brake calipers overhaulled by Biggred
Ferodo DS2500 pads
Braided brake hoses - I know some will say this only improves 'feel' however I was thinking if I'm wasting effort expanding the rubber hoses then that effort is not available at the pads.
Motul high boiling point brake fluid
New rear wheel cylinders

Anyway I must admit after bedding the pads in the brakes are really good, I took the car for a blat across country and didn't get any brake fade or sponginess. I know all of this is subjective dependant on driving style and what you like and are prepared to except in your brakes. It took a while to remind myself that the brakes are not as instant as I have been used too, however for brake 'feel' and modulation under braking I'm more than happy.