Other Cars (British & British-Inspired)

a place to discuss all our other favorite cars, especially the modified and/or V8 ones

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Roy McKnight

(5 posts)

04/07/2010 08:05AM

Main British Car:

Daimler Dart SP250 upgrades
Posted by: roymck
Date: October 12, 2010 05:44AM

Hi Anybody got any tips on getting more power from the Daimler 2.5 Hemi engine . Thanks Roy

Bernard Holzberg

(59 posts)

07/18/2008 11:12AM

Main British Car:
1975 TVR M series Ford 331

Re: Daimler Dart SP250 upgrades
Posted by: slow_M
Date: October 15, 2010 12:46PM

Yup, [www.youtube.com]
Check Grassroots Motorsports forums, talk to vintage racers....

What's your plan? Vintage racing?

Art Gertz
Winchester, CA.
(3170 posts)

04/24/2009 11:02AM

Main British Car:
74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L

Re: Daimler Dart SP250 upgrades
Posted by: roverman
Date: December 26, 2010 01:01PM

Roy, Your "Mighty Mite", hemi design was campaigned quite successfully in USAC "Midget" racing. A full feature in Hot Rod Magazine, 4 decades ago ? Owner/designer/builder, used "AutoCad" and maybe FEA. to design the cahssis,(very early application). Lil' hemi loved alchohol and embarrased a lot of race designed engines, like Offy. You may find article in "Hot Rod" archives. I don't know if you can use any 4.5L (Majestic) engine pieces for up-grades. Good Luck, roverman.

Terry Handley

(4 posts)

11/07/2011 07:33PM

Main British Car:

Re: Daimler Dart SP250 upgrades
Posted by: Jagpro
Date: November 13, 2011 10:44AM

Hi Roy,

Most of the performance mods that have been done to the Wee Daimler V/8 have been to either comply with race rules or very simple things that can be done easily with the biggest mod being a camshaft with slightly more duration, save that in years gone the Brits were big on Supercharging the 2.5 V/8 for drag racing, tough little critters when prepared properly and the longevity is good too.

My approach to the Daimler 2.5 V/8 is to bore and stroke it to 3.3 + litre, the forged steel crankshaft lends itself to being offset ground and welded on it's four conrod journals, the bore can from memory be bored .060".

The rest of the mods are as one would do to any engine, the standard Daimler headers are not too bad for most applications fine until the camshaft duration is over about 270 degs @ about .050" drop.

The Triumph Bonneville Thruxton or the Triumph Trident 750 Camshaft Grinds work well, one has to keep in mind the cam followers "lifters" guides have to be extended by welding and then machined depending on the camshaft lift and how much the base circle has been changed.

The steel camshaft really needs to be hardfaced welded on the lobes to get any decent grind on it.

There is not much if any over the counter hot up parts for either of the V/8's.

The 4.5 litre variant is a wee bit wider and longer then the 2.5 engine but not as long as some dodgy specs say it is.

The 4.5 V/8 will not bolt straight upto the SP250 Bellhousing, the gearbox that was usually fitted to the 4.5 V/8 SP 250's was the Jaguar Moss G/Box, the one I saw was the early Xk120, MK5 type Jag Moss box with the large flat rear mount.

Once one takes the heavy Dynamo off the 4.5 V/8 it's weight is down to the same as the 2.5 V/8 with it's Dynamo fitted give or take a couple of lbs.

I have a Daimler 450.... a Daimler 240 "Mk2 Jaguar style Daimler" with a 4.5 V/8 fitted, an absolutely awesome performer -v- any Hotted up Mk2 Jag whether it be 3.8 or 4.2.

There has been over the years many Daimler Darts/ SP250's with 4.5 V/8's fitted mostly unsuspecting onlookers did not know nor were they told. There was a bunch of new 4.5 engines and parts of shipped to the US and the majority of those engines found their way into low mileage and some brand new SP250's, cheater engines if you like, although the so kitted SP's had heaps of power and went like scaldd cats down the straights the chassis and rear end was not upto the extra power and torque of the larger engine.

Most folk that have ever pushed any Daimler SP's to their limits either on the road or at the track know that it has a few hinges in it's chassis that hold it back from being able to show the full potential of any V/8 engine nevertheless there was in years gone one that won it's class on many occasions and won a major race at Bathurst Australia's Mount Panorama, from memory the same car was used to win a Racing Championship mind you the driver was thought by some to be the best driver in OZ at that time, this was in realtime 1960's not vintage racing.

Whatever route you take to improve the performance of the Daimler 2.5 litre V/8 at the end of the day it would have to be the best sounding V/8 of all time and it's probably fair comment to say that the Daimlers hinges would be no less or no more then those Corvette Whales that could be beaten by a good MGB when there was a few twisty bits.

I will maybe post some pics of our Daimler 450 some time.


from Down Under

David Witham
Warwick UK
(115 posts)

06/12/2008 11:20AM

Main British Car:
MGB 1974 and MG ZT 160 turbo 2005

Re: Daimler Dart SP250 upgrades
Posted by: djw090
Date: November 14, 2011 08:17AM

I would be very interested in pictures and more info on your Daimler 450. It is unusual to find someone who knows so much about modifying Daimler V8s.
I have never seen a 4.5L Dart at a car show in the UK.

Martin Sinclair
Dorset, UK
(1 posts)

08/16/2018 09:11PM

Main British Car:
Daimler SP250 1962 v8 2.5

Re: Daimler Dart SP250 upgrades
Posted by: Hawkyork
Date: August 16, 2018 09:22PM

Has anyone details of Russ Carpenter’s mod to add a header tank to the Dart cooling system?

Had various replies, thanks to all!

Edited 1 time(s). Last edit at 11/07/2018 08:59AM by Hawkyork.

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