Solved - NEH 3873: Lester-MG Jeff Sparrowe Special (sometimes referred to as Morgan-MG)

[Carnut]

What's this car exactly, who built it and when - for 1 point?:

Remember - solving puzzles using 'Google Search by Image' is BANNED on AutoPuzzles!

[Carnut]

Experts?

[Carnut]

Pro's will have this one in a jiffy..

[Paul Jaray]

Morgan-MG Jeff Sparrowe Special, 1959.

[nicanary]

Your photo shows a Sebring Sprite 

[Paul Jaray]

Oops..fixed

[Carnut]

You've identified the right car, but I'm not sure the photo you've posted is the same one (note the completely different windscreen..)
The puzzle picture shows it racing at Goodwood in 1959.
There is some discussion about the basis of this car.  Whilst is does seem to have a Morgan chassis (Jeff Sparrowe was a well-known Morgan racer) and is registered as having a 1098 cc MG engine, there are those who think it used the chassis and engine of an MG K-type!  I'll go with the Morgan ID..

[Paul Jaray]

I changed the pic...I got the wrong one.
Jeff Sparrowe built at least other 2 specials in late 40s, SMS I and SMS II...one was a Rudge-engined special with an Austin chassis and the other was a modified Marwyn.

[barrett]

This car is actually a Lester - The chassis is the eighth Lester T51 chassis, fitted with 1100xx XPAG and GRP body by Sparrowe, so no Morgan connection here. Apparently it survives in running order, though I don't know what it looks like today

[Carnut]

This car is actually a Lester - The chassis is the eighth Lester T51 chassis, fitted with 1100xx XPAG and GRP body by Sparrowe, so no Morgan connection here. Apparently it survives in running order, though I don't know what it looks like today

I knew there was some doubt about whether it really did have a Morgan chassis (as I posted above).
It's probably better to change the heading..