TR7 Sprint conversion - engine rebuild help

[jeffremj]

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by moodyblue</i>

Strange, with the deeper timing cover on the Sprint I would have thought that the Sprint pulley would be the long one.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">Don't forget that the 16V was designed to fit in a Dolomite, and there was no extra room in front, so that is why the distance from the sump to the end of the pulley is the same for the 8V and 16V.

[moodyblue]

Good point! I'll compare flywheels, oil pick-ups and the pulleys at the weekend if I have time. My job is getting in the way of my restoration, but I've loads of parts to buy so I'd better go and earn some wedge tokens.

[Stag76]

You have to use the TR7 sump, so maybe the TR7 oil pickup is made to fit into the lowest point of that sump.

TR7 Convertible
Sprint Motor
MegaSquirt EFI

[dursleyman]

From the engines I have looked at the oil pick ups seem to be the same on both TR7 and Sprint, I think the different sump doesn't affect that area.
On flywheels, the TR7 ones I have are about 2kg heavier than the Dolly Sprint made up by more material on the back of the flywheel - see pictures.




Russ

1980 TR7 Sprint DHC, 1981 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

[img]http://i1040.photobucket.com/albums/b410/dursleyman/TR7%20web%20picture/IMG_0479-Optimized.jpg[img]

[moodyblue]

Excellent, thanks for posting the pictures, I can't go wrong now, and it will be the Sprint flywheel I'll use. I agree about the oil pick-up as I didn't notice any difference and they have the same part ID. Thanks again to all of you for taking the time to respond. It's good to get answers to these questions as so much rubbish is written in books and online.

TR7 or Sprint oil pick-up
Sprint pulley
Sprint Flywheel
[:)]

[FI Spyder]

It is a good idea to grind out the rough machined oil holes in the block as they don't match the holes in the pump, partially blocking off the flow. It's something Dolomite owners do and can make up to a 25% difference in flow.





- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[moodyblue]

I never thought of that. You would think that they would have machined the blocks correctly in the factory. Is that a picture of one that's been done?

[FI Spyder]

No, you can see it roughly marked off with a marker for demonstration purposes. I would trace the holes on the pump then cut them out and trace the holes on the block. You want to make sure no grindings get in the engine or do it before it goes to the engine shop for hot bath. That's not the only area. There is also a rough opening to water pump that should be ground if your in that position to maximize water flow and cooling (at the top). It's all in the manufacturing philosophy of "good enough".



- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[moodyblue]

Thanks for the tip. Time to get the pencil grinder out!

[moodyblue]

I'm going to fit the sprint flywheel this week, but my workshop manual isn't very clear about this task. Should the mark on the flywheel hub align with the mark on the engine/gearbox backplate when piston No.1 is at TDC?

[FI Spyder]

Re: difference of 16V flywheel. A lighter flywheel allows the engine to rev quicker, a plus in the higher reving 16V engine that's why the Sprint flywheel is lighter. The trade off is a heavier flywheel smooths out the idle a bit. It's a trade off. Heavier flywheels can be machined to be lighter by a machine shop that knows what they are doing (where to machine and by how much). A friend had his Spitfire machined lighter when he changed to UK spec to get a quicker reving engine.

[moodyblue]

I see, that explains why the TR7 one is so heavy. I'm going for the revs with the lighter sprint flywheel. I was looking at the engine today and by aligning the mark on the flywheel hub with the mark on the gearbox plate, No1 piston is indeed at TDC. This setting should put the crank, front pulley and the flywheel in balance as it was in the factory, I hope. Still strange that the manual states that the crank and flywheel should be marked if removed, then shows a picture of the factory marks with alignment instructions.