Sprint head on 1850

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Sprint head on 1850

#1 Post by new to this »

Just curious can you fit a Sprint head on a 1850 engine block ? and how would it run ?
I know you may need to fit a Sprint timing cover
Carledo
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Re: Sprint head on 1850

#2 Post by Carledo »

I'm sure you CAN as you can fit a Sprint head to a TR7 block or use a TR7 block with Sprint internals and head. I gather it's also possible to sleeve an 1850 block and use it in a Sprint.

So it's POSSIBLE, but why would you want to?

You would indeed need to fit the Sprint timing cover, but also do something with the crankshaft timing gear as the 1850 only has a single row chain. Whether you can mix and match bits at the bottom end to match a 2 row gear and pulley to the single row 1850 crank is beyond my wheelhouse. You might also need to do something with pistons as the Sprint has valve cutouts not present on the 1850 pistons. Jeroen would probably know, he does this sort of thing for fun!

Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

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xvivalve
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Re: Sprint head on 1850

#3 Post by xvivalve »

So it's POSSIBLE, but why would you want to?
Lack of availability of suitable Sprint blocks/pistons. Using an 1850 block bored or sleeved to 90.3 mm allows use of plentiful standard Sprint pistons. You'd not put a Sprint head on an 1850 block without bringing it up to Sprint bore as the combustion chamber would have a peculiar shape.

The cranks are identical between Sprint and 1850, so you simply replace the timing gears, chain and tensioner with the duplex varieties along with the cover, but you'd also need a sprint bottom pulley or machine the 1850 one down to size.

Con rods are also different between 1850 and Sprint.
Carledo
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Re: Sprint head on 1850

#4 Post by Carledo »

xvivalve wrote: Sun Apr 23, 2023 1:44 pm
So it's POSSIBLE, but why would you want to?
Lack of availability of suitable Sprint blocks/pistons. Using an 1850 block bored or sleeved to 90.3 mm allows use of plentiful standard Sprint pistons. You'd not put a Sprint head on an 1850 block without bringing it up to Sprint bore as the combustion chamber would have a peculiar shape.

The cranks are identical between Sprint and 1850, so you simply replace the timing gears, chain and tensioner with the duplex varieties along with the cover, but you'd also need a sprint bottom pulley or machine the 1850 one down to size.

Con rods are also different between 1850 and Sprint.
You misunderstand me! I fully appreciate the point of using a sleeved/bored 1850 block or a TR7 block to replace all the Sprint engines that been blown up, cracked, or bored to their limit. Or simply to compensate for the shortage of oversize Sprint pistons.

What I couldn't understand is why anyone would want to create an 1850 16v! Which is what Dave seemed to be implying!

Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.
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soe8m
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Re: Sprint head on 1850

#5 Post by soe8m »

Carledo wrote:
You misunderstand me! I fully appreciate the point of using a sleeved/bored 1850 block or a TR7 block to replace all the Sprint engines that been blown up, cracked, or bored to their limit. Or simply to compensate for the shortage of oversize Sprint pistons.

What I couldn't understand is why anyone would want to create an 1850 16v! Which is what Dave seemed to be implying!

Steve
The difference in cylinderbore and compression ratio won't make that work.

Jeroen
Classic Kabelboom Company. For all your wiring needs. http://www.classickabelboomcompany.com
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