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1300 vs 1500

JPSmit

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these are the same block aren't they? except for the bore?

are they interchangeable? is there an advantage of one over the other? are the thrust bearings fragile for 1300's also?

This for a 1500 Midget. I have a line on one.

thanks
 
Physically the engine's are the same size but I cannot answer regarding the internal differences between the two. However, what you will have to do if you fit the 1300 to your Midget is bush the mounting holes of your 1500's flywheel to work with the smaller bolts used to hold the flywheel to the 1300's crank.
 
Bore size is the same I believe, the displacement increase came with an humongous increase in stroke.
 
Didn't I hear that the 1300 is a preferred power plant?
 
JPSmit said:
these are the same block aren't they? except for the bore? are they interchangeable?
Yes...and no. I believe that you can interchange cranks, pistons, rods and such between the LATER 1300 (FH, FK and FL series) and 1500 (FM and FP series), but NOT with the earlier 1300 (FD, FE series).
 
Andrew Mace said:
JPSmit said:
these are the same block aren't they? except for the bore? are they interchangeable?
Yes...and no. I believe that you can interchange cranks, pistons, rods and such between the LATER 1300 (FH, FK and FL series) and 1500 (FM and FP series), but NOT with the earlier 1300 (FD, FE series).

You could if you want put a late 1300 crank in a 1500 block, and it will work (don't know why you would want to do this) but you can NOT put a 1500 crank in a 1300 block since it will hit the side of the block.
A 1500 head will work on a 1300 (I have a 1500 head on my 1300) but it needs ALLOT of machining to get the compression ratio up to normal.
Pistons pistons, rods and crank are all different between 1300 and 1500.
 
JPSmit said:
these are the same block aren't they? except for the bore?

are they interchangeable? is there an advantage of one over the other? are the thrust bearings fragile for 1300's also?

This for a 1500 Midget. I have a line on one.

thanks

If you have a 1300 available get the # so to find out if it is a small crank or large crank. the small crank (earlier) engines rev up much more quickly than the later large crank. thrust bearings have the same issues for both 1300 and 1500. Of course since you have the block out of the car, just put new, upgraded bearings in and you will be fine for quite a long time.
 
Another thing I'll throw into the pot, on the 1500 blocks, which has no cam bearings, you can install cam bearing in a 1500 block with no machine work, by using a 1300 cam and 1300 cam bearings in the 1500 block, I've built a few race 1500 engines this way.
 
The 1500 blocks have a "relief" at the bottom of the cylinder where it projects into the sump to clear the rod. The 1300 block (big journal) does not have these reliefs. SO, you can use a 1500 block as a 1300, but not vice versa, unless you can create the relief. You may want to doulbe check this before you committ to this, but I have looked at both blocks before for this very reason. I have one of each in my storage building.

OK. I see 70 Herald already addressed this.
 
I am not an expert on Spitfore motors, but talk to the guys in the club who work on them, a couple have some pretty heavily modified motors, the 1500 of course has more displacement so an inherent advantage.

I believe the 1300 with the shorter stroke will rev a little higher safely, I think at least one club member with a modded Spit 1500 talked about or actually did put a 1300 in there.

If you are staying stock I don't know if one is more reliable than the other, the bigger motor will give you more torque.
 
Wow, more difference than I thought! Have had no reply from my response to the ad so it is now a moot point - thanks though!
 
What did you have in mind JP? Why a swap out? Oh, BTW, seems my euro dual adapter for the rear bowl would have worked out o.k. I had a defective vent in my gas cap that was causing the "vapor lock" issues. Jujst letting you know in case you still were thinking about about the swap w/o cutting.
 
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