engine swap?

[mike91]

hi,
i am just about to start tuning a 1500 dolomite, and have been doing some research into the 1500 engine. and the general consensus is that although you can get some power from it, it is not at all rev happy. and can put some serious strain on the crank.
i was planning to do some fairly serious tuning work on it, so that isn't sound too inviting to me!

what possible engine swaps can you do in a dolomite, other than the obvious, sprint, v8 conversion.
would it be possible, for instance, to fit a ford xflow engine in it?

thanks.

[Clive]

xflow!!!!!
I know vx redtops are used, and I see no reason why a zetec wouldn't go in either. Of course the toyota 4age, maybe the nissan 200sx turbo if you want BIG power!
Re the 1500, what were you thinking of as a target power?
Mine has a "tuned" 1500 fitted, but has not been set up properly yet :B (lack of time, but is my every day car) No sluggard, and will be better. May get 90+bhp, and as long as you do not want to be at 6000+rpm too regularly they are fine. However, not cheap to build :-/ at least compared to a zetec for £50 which can give 150bhp no sweat all day long.

[mike91]

i wasn't going for 'big' power as such.
i was more looking for a mid-powered engine that i can rebuild for more power. so a modern engine wouldn't really be an option for me.
i was looking for around 100 plus or minus.
out of interest, what have you had done to your 1500?  :)

[Darren Sharp]

Dear Mike

The advice about max tuning a 1500 is pretty sound. As the last of the SC series engines it was both bored and  stroked out as far as possible and really does not like to rev. ( It started out as the Herald 948 and that was developed from a mid fifties Standard 8 engine). Also the breathing is quite restricted and no one has yet developed an SU manifold that improves it much so you would need to look at Webers, Spitfire/Midget kits are availiable but are pricey at around £400 but they do look the business. The 1300 Engine is more oversquare and there is lots of advice on the Spitty forum about what can be done from simple stuff right down to blueprinting and big Weber twin 40/45s that can develope massive safe power gains over and above the 1500 spec. Fitting a 1300 lump from a Spitty is a straightforward(ish) swap and has obvious advantages as all the rest of the drivetrain remains unchanged or you can go for Sprint bits which are often availiable on line . Remember that in fine fettle a Sprint was good for 115+MPH and they also did a Quaife limited slip Diff option. I love the Sprint but have always found them to be rather fragile in everyday use.

I have seen a fantastic Vauxhall 2.0 NE  8v conversion that used an Omega 5 speed box and a bespoke ECU. This thing was a real Q car. I owned an Astra SRI with this lump and it had diesel like Torque and was good for massive acceleration in top from a virtual standstill up to 130MPH. ( Discovered when the power steering pump ignited and I had no option but to accelerate as fast as possible and blow it out or stop and watch the car burn). Try to avoid the later 16v as it is revvy and gutless in comparison, (alright in a modern with high gearing but no grunt) The 2.0 NE was fitted to Mark 3 Astra's and Mk 3 Cavaliers up to about 1993 so there are plenty about. I believe The owner is a club member so ask around. It was displayed at Stoneleigh last year.

I have also seen Stag and Rover V8s fitted to Dollies the former required 3" to be added to the front wings so not to practical. The Rover was a good fit but the owner confessed that it caused the car to Torque Steer wildly when provoked as the torque tore at the subframe mountings twisting the steering wheel out of his hands. You will need to replace the Mountings with good racing poly if any serious power gains are applied and an export brace is also a good idea as are Sprint/GT6 brakes or Princess four pot calipers. Bigger engines and massive Carbs will also shrink your journey range as the tank only holds 12.5 Gals.

I am contemplating an engine/drivetrain swap at some future time and I will probably buy another old Dolly as a mule to test it all out. I might have to look for some sponsorship though. Please keep us posted with your project. I am sure it would be very welcome in Club Torque. Triumph 6 cylinder lumps are longer than the Stag so it would unlikely to be an easy fit. They are great but I would think that they would end up making the front of a Dolly like a pendulum as they are staggeringly heavy.

Darren

[Darren Sharp]

Dear Mike

I should also mention that a good Electronic Ignition and a new dizzy (or a 123 Dizzy) will give you significant power and smoothness gains. I think you could achieve 100 quite easily if these were coupled to a four branch manifold and a pair of rebuilt SU's with richer needles. This combo would also sound brilliant in tunnels and give a good powerband.

Don't forget the 1850 as they tend to be far more reliable than sprints and have the power you are looking for as standard. They are getting rare though.

Darren

[Clive]

Unfortuanately no 4 branch manifold is available :'(

Mine was a "luck" find. Having zero oil pressure on my arrival at SEM in May this year, towing a trailer of assorted tat to sell, a Volvo pulls up next to me and opens the tailgate. Inside I noticed a dusty but new looking short engine. Turns out theh owner had it as a goldseal engine back in the early 90's for his spit, decided he wanted more power after only a couple of thousand miles so...
Head went to Kingston Sports Cars, where it had some light porting, bigger valves and a heavy skim to get the CR to 10.5:1. Supplied with a TH5 cam and new OE followers.
Short engine went to Oselli. Crank tuftrided, flywheel lightened, then all fully balanced etc etc. Supplied with new VP2 bearings and uniprt clutch (balanced with the crank/flywheel and front pulley)
This then sat inside his house unused and unassembled until I bought it and put it together. I currently have the 1500 type cast manifold and twin SU's fitted, but hope to "bodge" a 4 branch manifold and fit a single HIF44 carb. I hope 100bhp is attainable, but will require a rolling road to get there with mods to the dizzy etc as well as carb needles. Fitting megajolt would be beneficial, but I am old fashioned sometimes :-/
If you want to avoid the costs associated with modding an engine (do not underestimate them, I suspect that the work on the engine I have would cost about £1000 today, allowing for the fact it had a full rebore/regrind too) then a TR7 lump will go in with an 1850/sprint front subframe.
Regarding uprated brakes the cheapo answer is to use an extra pair of dolly calipers. Unfortuanately the GT6 ones will not fit easily, but Trackerjack produces a conversion kit or indeed just the conversion brackets for fitting bit brakes ;) Mine runs std (new) discs and mintex pads. OK, not brilliant :o

[Toledo Man]

it is possible to get more power out of the 1500 lump. Balancing and lightening the crank & pistons should help it rev better. Porting the head will help with the flow. The 1500 exhaust manifold with the twin pipe outlet is the best of the standard exhaust manifolds despite the troublesome manifold-to-downpipe gasket joint. Unfortunately the Spit's tubular manifold won't fit because it is fouled by the subframe so some "fettling" is needed. One alternative would be to have a manifold specially made but this is costly. If HS4 carbs are to be used with a standard exhaust manifold a heat shield will have to be fitted to avoid fuel vapourization. Stainless ones can be had from eBay for sround £20ish (don't quote me on that. Just had a look and I can't find any) There are other ways of reducing the underbonnet temperature (lagging the exhaust manifold, better airflow management, etc) to avoid fuel vaporization. Clive's already covered the brakes. and the slant-4 swap which would also involve some rewiring because the battery's on the offside in slant-4 engined cars. It is reckoned that a tuned 1500 engine can produce in excess of 100bph. The best thing would be to visit the TDC forum wher you'll find the OHV engine guru who can tell you what can be done. (he can do it for you as well)