Daimler 250 V8 engine mods
Discussion
Nick_F said:
Would the 4.5 be any heavier than a Jag XK unit?
I've been thinking on this again Nick. I haven't found any actual figures of relative weights of the 4.5 V8 and, say, a 3.8 XK but you're right in suggesting there can't be much between them. Also, if the transmissions are in the same location longitudinally, the the C of G of the V8 might actually be further back than the six. Hmmmm. I have spoken to somebody over a year ago who was selling a 4.5 on eBay. He seemed to confirm that he knew it would fit into a Mk2 with some mods to the inner wings so it must have been done. Wish I'd kept his number!!Nick_F said:
This suggests 400lbs minimum for the Daimler, and a more accurately defined 570lbs or more for the XK including bolt-ons - perhaps not much in it?
Interesting link - thanks Nick.I see a page on Wickipeadia gives 419lbs for the 2.5 and 498lbs for the 4.5. All these figures are, of course, relative to how the engines are dressed.
Carsie said:
Dave, read your posting with interest 
I seem to recall something about the pistons on a Triumph Bonneville Motorbike being suitable for tuning a Daimler 2.5. I'm sorry I don't remember anything much more than that or the context. By the way don't forget the fabulous story of the Majestic engine being put into the Mk10 for evaluation (as well as the XJ13 Quad Cam of course) - Have fun!
I seem to recall something about the pistons on a Triumph Bonneville Motorbike being suitable for tuning a Daimler 2.5. I'm sorry I don't remember anything much more than that or the context. By the way don't forget the fabulous story of the Majestic engine being put into the Mk10 for evaluation (as well as the XJ13 Quad Cam of course) - Have fun!Hi Carsie
Yes, I recall the consternation caused when the 4.5 was tested in the Mk10 and apparently blew the socks off the Jag engined car. However, the idea was swiftly dumped to avoid any damage to the Jag brand' image - or so we're told. There seems to be a lot of mythology going on here which gets reinforced every time the story is told. Same with the 'Bonneville' connection. Whilst there is a general similarity in the piston/combustion chamber shape between the Daimler and this Triumph motorcycle engine (no surprise due to Edward Turner's involvement in both) I don't think there are any actual commonalities between the two engines. I have seen it written that Bonneville pistons were used as the basis for the 2.5 Daimler engine. I'm not sure if this is actually true - anybody know for sure?
However, I have read in a more reliable article re the development of the Daimler engine (Brian Long?) that, at one time, a cam profile based on the Bonny was tried in the Daimler and produced spectacular results.
RW774 said:
I`m amazed sometimes that the average person knows more these days than the factory did back in then! .
Hi RW, Exactly what I was trying to get across in my recent post"consternation caused when the 4.5 was tested in the Mk10 and "apparently" blew the socks off the Jag engined car. However, the idea was swiftly dumped to avoid any damage to the Jag brand's image - "or so we're told". There seems to be a lot of "mythology" going on here which gets reinforced every time the story is told. Same with the 'Bonneville' connection. Whilst there is a general similarity in the piston/combustion chamber shape between the Daimler and this Triumph motorcycle engine (no surprise due to Edward Turner's involvement in both) I don't think there are any actual commonalities between the two engines. I have seen it written that Bonneville pistons were used as the basis for the 2.5 Daimler engine. "I'm not sure if this is actually true" - anybody know for sure?
However, I have read in a more reliable article re the development of the Daimler engine (Brian Long?) that, at one time, a cam profile based on the Bonny was tried in the Daimler and produced spectacular results."
Yep, a lot of crap gets put in writing by journalists and contributors alike. Trouble is, it gets taken in as gospel then gets regurgitated as a good story and the myth is established to confuse good souls even 50 years down the line! That's why I'm treading carefully here.
Anyway, as interesting as this all has been, I'm sticking with the 2.5, I am going to look at sleeving to up the capacity as you suggested but am still uncertain about pistons to suit, I am determined to build my own inlet system with fuel injection, will look at the heads and exhaust manifolds and go from there.
Always good to hear from you! Dave.
Well, thanks for that guys. I need some ideas here. I, of couse, know the basics of EFI but have never had to apply it to a new project before. My starting thoughts were to try and adapt an existing production system - plenty available in scrapyards! However, I have taken in all the points made by various posters to this thread with great interest. Maybe an aftermarket system would give me better flexibility? I know these exist but have no experience of them so I'm all ears!
(Will be out for the rest of the day. Have to move my '69 XJ6 Mk1 (manual) from friend's garage before his wife goes spare! Problem - where the hell am I going to put it?? Then there's the '65 MGB GT and the Humber Sceptre round at Bob's - his wife none too happy either. Then there's the XJ12C and the Daimler 4.2 at ...... oh my goodness, what have I done!!!)
(Will be out for the rest of the day. Have to move my '69 XJ6 Mk1 (manual) from friend's garage before his wife goes spare! Problem - where the hell am I going to put it?? Then there's the '65 MGB GT and the Humber Sceptre round at Bob's - his wife none too happy either. Then there's the XJ12C and the Daimler 4.2 at ...... oh my goodness, what have I done!!!)
jith said:
But whatever you do Dave, don't even consider using K-Jet with its rock solid, tried and proven, almost 40 year totally dependable history on such mundane cars as the Quattro and Saab turbo!! It would be too much trouble! And all of it available second hand! 
(Sorry lads, couldn't resist it!)
Not ruling anything out at this point. I have sung the praises of K-Jet myself in years gone by. Had a run of Sciroccos (Scalas, Storms and Gtx) and a couple of Golf Gtis, all with K-Jet. Totally reliable as far as I was concerned and much fun had. But is it the best way to optimise my project in 2009 (2010 more realistic!). Must dash - Jag to move! (Sorry lads, couldn't resist it!)
[quote=aeropilot
Brave man......
But......turbo charging a Daimler Hemi will be interesting, and expensive too with having to get new low compression pistons made for it, and a whole new carb/inj/manifolding system for it.
Just put a small block Ford V8 into, a very compact V8 (as per the Sunbeam-Tiger) ......... easy horspower (more than you'll ever get out of the much rarer Daimler) for an awful lots less hassle.
[/quote]
Whilst this is an aside from my original topic, it's an interesting idea nontheless! A few comments: nice idea but dont think the Daimler unit is really appropriate for an 'Arrocuda'. Agree with the above that a small block Ford would be an easier and more rewarding conversion. You might read earlier in my thread that I had a mildly breathed on 260 ci Sunbeam Tiger at one time and performance up to about 80 mph was incredible. After that, it was f***in' dangerous, wouldn't stop easily or go round corners but made a glorious sound. All this was in central Africa. I once set off for work at five past seven and still managed to get there at seven o'clock - that's fast! Just by the way, the standard compression ratio of the Daimler is only 8.2:1. I've been searching for suitable pistons to cope with a possible rebore to 3.0 litres but no luck so far. Also, I'm seriously doubting the feasibility anyway of sleeveing the Daimler to up the capacity. As far as I can see, it would mean cutting right into the waterways and, although this is dimensionally possible (if I can find some pistons!), I think it would weaken the block considerably. But no doubt, someone will tell me different!
Brave man......
But......turbo charging a Daimler Hemi will be interesting, and expensive too with having to get new low compression pistons made for it, and a whole new carb/inj/manifolding system for it.
Just put a small block Ford V8 into, a very compact V8 (as per the Sunbeam-Tiger) ......... easy horspower (more than you'll ever get out of the much rarer Daimler) for an awful lots less hassle.
[/quote]
Whilst this is an aside from my original topic, it's an interesting idea nontheless! A few comments: nice idea but dont think the Daimler unit is really appropriate for an 'Arrocuda'. Agree with the above that a small block Ford would be an easier and more rewarding conversion. You might read earlier in my thread that I had a mildly breathed on 260 ci Sunbeam Tiger at one time and performance up to about 80 mph was incredible. After that, it was f***in' dangerous, wouldn't stop easily or go round corners but made a glorious sound. All this was in central Africa. I once set off for work at five past seven and still managed to get there at seven o'clock - that's fast! Just by the way, the standard compression ratio of the Daimler is only 8.2:1. I've been searching for suitable pistons to cope with a possible rebore to 3.0 litres but no luck so far. Also, I'm seriously doubting the feasibility anyway of sleeveing the Daimler to up the capacity. As far as I can see, it would mean cutting right into the waterways and, although this is dimensionally possible (if I can find some pistons!), I think it would weaken the block considerably. But no doubt, someone will tell me different!
arrow v8 said:
Hi Dave..... For me the 5.7 litre Ford unit is not a practical solution as I would have to do some serious mods to physically get it in. The Sunbeam Tiger isn't really a fair comparison as the Rapier was designed for a four pot banger which had to be slant mounted for the bonnet to shut but would probably have been different if they had intended to put a larger engine option in the sales brochure.
Tim.
Hi Tim, Well, you certainly have some ambitious projects in your mind! Take some advice from an old bodger and focus on one project at a time. That way you stand a chance of actually achieveing your dream. Made the mistake myself of having too much on the go all at one time (always tempted to buy 'bargain' classics just because they were there) you end up going nowhere!Tim.
As for the Ford V8, the one in the old Tiger was actually only 4.2 litres and as a cooking engine pumped out less than 200bhp in stock form. The Tiger was basically the original Sunbeam Alpine sportscar, made with the same basic four-pot Rootes engine as in your Arrow. Your Arrow engine bay is slightly wider but they had to slant the engine to gain a lower bonnet line as you say. So there's definitely room to fit the small block Ford (wasn't suggesting the larger 5.7 and ++ V8's).
For better economy and ease of sourcing parts, the Rover is a better bet or you should really consider a modern V6. All I was saying is that, in this instance, I really don't think the Daimler is the way to go - but its your choice! I have plenty of experience with XJ's (got 6 at the moment) and suggest you go easy before chopping one. Sills and floors are always suspect, even when they look solid, esp on the coupes. Same with XJS's. Take some time and learn to weld properly. Its easy enough these days with MIG and TIG etc and will pay you back a fortune over a lifetime plus open the door to some of your wilder schemes! Good luck anway.
Dave.
tevie54 said:
Hi, just logged on and was interested in the Daimler V8 subject, i've been a fan of these engines for many many years and as far as i remember, the designer, Edward Turner worked for Triumph motorcycles for many years and used his experience in this field when designing the V8, it is rumoured that during development, the engine was fitted with eight Amal bike carbs, it revved to 9000 rpm and produced 400 bhp. It is a very strong engine. I remember reading an article in Custom Car magazine back in the early 80's about drag racing using a Daimler V8 and the use of Triumph Bonneville pistons goes somthing like this. The Triumph came with 'standard' compression at about 8.5 to 1 or 'high' compression which was about 10.5 to 1. The gudgeon pins were the same size as the Daimler and the design of the combustion chamber was the same, why change an excellent design? The problem with using Bonneville high comp pistons is the bore size of a standard Daimler engine is slightly too big, so you have to use oversize Bonneville pistons, but the next size up is then too big for the standard Daimler bore so you end up boring out the Daimler block and using +25 or +50 Triumph Bonneville High compression pistons. There will obviously be a performance gain from the higher compression but alternative fueling and exhaust systems will bring extra power as well. As a Triumph Stag owner i could never understand why the factory didnt use the Daimler engine, seeing as it was designed by a Triumph man, this would have eliminated much development time and cost, and with a little more fettling would easily have put out as much if not more power than the stag unit.
Hope this helps a little.
Steve Hill
Hope this helps a little.
Steve Hill
Thanks for that Steve,
I'm still scratching my head on this one but want to make a start after Easter when I will have more time on my hands (65 on 5th April!) and will have sold a house so have some cash to play with!
If you read the full thread, you will note all sorts of advice as to what I might do. One idea was to increase the capacity to ideally 3 litres by boring and sleeving. But a look at the drawings would seem to indicate there isnt enough meat in the block to do this - would mean breaking right into the waterways and, even if the new liners could be sealed, cooling flow would be reduced and general block strength compromised. Has anyone any experience of this type of thing? Also, what pistons could I possibly use? Have searched in vain for anything standard with a pent top and the right gudgeon pin position - or even close to modify.
As for the up-sized Bonny racing pistons, these sound a good idea if I stick to circa 2.5 litres but again, are these still available?
This whole thread started because I wanted to increase the power of my Daimler 250V8 manual by adding fuel injection for a serious road car I'm restoring (dont want dragster performance or anything too silly!). I'd like to stay true to the Daimler heritage but would like to end up with maybe 250 bhp. Have considered but rejected fitting the 4.5 Daimler V8 and now even looking at a modern Jag 3.2/4.0 litre V8. Will be chucking the original manual box for something more appropriate.
My quest goes on!
Thanks for that Steve,
I'm still scratching my head on this one but want to make a start after Easter when I will have more time on my hands (65 on 5th April!) and will have sold a house so have some cash to play with!
If you read the full thread, you will note all sorts of advice as to what I might do. One idea was to increase the capacity to ideally 3 litres by boring and sleeving. But a look at the drawings would seem to indicate there isnt enough meat in the block to do this - would mean breaking right into the waterways and, even if the new liners could be sealed, cooling flow would be reduced and general block strength compromised. Has anyone any experience of this type of thing? Also, what pistons could I possibly use? Have searched in vain for anything standard with a pent top and the right gudgeon pin position - or even close to modify.
As for the up-sized Bonny racing pistons, these sound a good idea if I stick to circa 2.5 litres but again, are these still available?
This whole thread started because I wanted to increase the power of my Daimler 250V8 manual by adding fuel injection for a serious road car I'm restoring (dont want dragster performance or anything too silly!). I'd like to stay true to the Daimler heritage but would like to end up with maybe 250 bhp. Have considered but rejected fitting the 4.5 Daimler V8 and now even looking at a modern Jag 3.2/4.0 litre V8. Will be chucking the original manual box for something more appropriate.
My quest goes on!
[/quote]
Thanks for the call John. Will be in touch soonest!
I'm still scratching my head on this one but want to make a start after Easter when I will have more time on my hands (65 on 5th April!) and will have sold a house so have some cash to play with!
If you read the full thread, you will note all sorts of advice as to what I might do. One idea was to increase the capacity to ideally 3 litres by boring and sleeving. But a look at the drawings would seem to indicate there isnt enough meat in the block to do this - would mean breaking right into the waterways and, even if the new liners could be sealed, cooling flow would be reduced and general block strength compromised. Has anyone any experience of this type of thing? Also, what pistons could I possibly use? Have searched in vain for anything standard with a pent top and the right gudgeon pin position - or even close to modify.
As for the up-sized Bonny racing pistons, these sound a good idea if I stick to circa 2.5 litres but again, are these still available?
This whole thread started because I wanted to increase the power of my Daimler 250V8 manual by adding fuel injection for a serious road car I'm restoring (dont want dragster performance or anything too silly!). I'd like to stay true to the Daimler heritage but would like to end up with maybe 250 bhp. Have considered but rejected fitting the 4.5 Daimler V8 and now even looking at a modern Jag 3.2/4.0 litre V8. Will be chucking the original manual box for something more appropriate.
My quest goes on!
[/quote]
Thanks for the call John. Will be in touch soonest!
BMWChris said:
I think 100bhp from a 2 valve road engine is a very tall order! It would be interesting - and if the design is as similar to the Triumph as people think then you could probably copy cam profiles, valve sizes and gas flowing from the bikes but then you would run into issues of driveability.
I think a modern engine would be easier, cheaper and better. Assuming you we willing to sacarafice originality. Jags, BMWs and Mercs all have smallish, lightish V8s though I understand that the electronics can be a little complex.
Hi Chris,I think a modern engine would be easier, cheaper and better. Assuming you we willing to sacarafice originality. Jags, BMWs and Mercs all have smallish, lightish V8s though I understand that the electronics can be a little complex.
I'm sure I've read somewhere that the Daimler factory tried a cam based on the Bonny with good results. The challenge I've set myself is really to get the most I can sensibly extract out of the original engine including adding fuel injection of some sort. But if I do eventually go for an engine transplant, I'd want to keep it in the family so would go for the new Jag/Daimler, if it would fit, rather than a BMW etc.
Cheers,
David
Hey V8250,
Thanks for that. Nice motor you had!
I am an experienced engineer but it's amazing what info and ideas this thread has brought up.
As I've said before, massive power isn't exactly what I'm after here. But I do think there is room for considerable improvement on the standard engine by using more up-to-date technology, especially fuel injection. I have always been a classic car nut, especially for Jaguars and have owned plenty (still do - see my other threads!).
But, as one of my final projects (65th birthday comin' up) I want to treat my lovely '67 250V8 to a proper make-over. Got the wires, some Coombes arches etc. I've had all sorts of advice including sticking in 8-litre Viper lumps to adding nitrous injection! Nope, that's not what I'm at. Just want to do one of two things:
either
1) professionally rebuild the existing engine, balance it as you suggest, gas-flow the heads, maybe add custom exhaust manifolds, maybe increase the capacity a bit if that is feasible, but principally to add fuel injection probably with a completely new inlet manifold. Despite some earlier postings, I don't see why 250 bhp is out of reach, maybe a tad more? And I'd probably want to replace the existing manual 4-speed + overdrive box with something a bit more modern.
or
2) might just consider putting in a modern Jaguar V8, at least keeping the heritage in tact.
Grateful for the thoughts and links.
Cheers
Thanks for that. Nice motor you had!
I am an experienced engineer but it's amazing what info and ideas this thread has brought up.
As I've said before, massive power isn't exactly what I'm after here. But I do think there is room for considerable improvement on the standard engine by using more up-to-date technology, especially fuel injection. I have always been a classic car nut, especially for Jaguars and have owned plenty (still do - see my other threads!).
But, as one of my final projects (65th birthday comin' up) I want to treat my lovely '67 250V8 to a proper make-over. Got the wires, some Coombes arches etc. I've had all sorts of advice including sticking in 8-litre Viper lumps to adding nitrous injection! Nope, that's not what I'm at. Just want to do one of two things:
either
1) professionally rebuild the existing engine, balance it as you suggest, gas-flow the heads, maybe add custom exhaust manifolds, maybe increase the capacity a bit if that is feasible, but principally to add fuel injection probably with a completely new inlet manifold. Despite some earlier postings, I don't see why 250 bhp is out of reach, maybe a tad more? And I'd probably want to replace the existing manual 4-speed + overdrive box with something a bit more modern.
or
2) might just consider putting in a modern Jaguar V8, at least keeping the heritage in tact.
Grateful for the thoughts and links.
Cheers
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