What Can be done with a 1300 SP motor

[Doogster]

Can anyone advise me some sensible things to do with a 1300 SP I have picked up as a temporary engine whilst I collect the parts for a bigger engine for my Buggy Project. Dont mind spending a little bit of money on the engine. I was thinking a better cam and maybe a set of twin carbs?  All advice greatly recieved.

[Zach Gomulka]

Stage one- Dual Kadrons, lighten the flywheel. Stage two- little bit of head work, flycut the heads for compression. If the engine runs now I wouldn't bother with a cam change, breaking open the bottom end is a slippery slope.

[Torben Alstrup]

Kads will be too much for that little thing. If time is not an issue, get a set of type 3 carbs and rebuild them, make the mandatory 60 mm staqcks, get the correct manifolds etc. and rejet. Better than stock muffler (A gutted muffler will get you a long way here) Bump the CR to 8,2 on medium grade and 8-5 on high grade fuel.. While tghe headas are off you can clean up the ports and do a better valve/seat job.
If you want to tear into the heart of it, a CB2280 or a W100 cam can work well, just make sure that you set the CR to the cam. On such small engines it is even more important that the CR is in the high end for the fuel.
You can ligthen the flywheel 1 kg and rebalance, or the classic conversion to a 12½ or 13 lbs 200 mm flywheel and then use a 3½ lbs pulley to get the crank weight on a smaller diameter. (This actually works well on small hopped up engines.)
Pretty soon you are on a whopping 60 hp.  but the fun factor by building it is still there 

T

[whirligig]

depends how far you want to go, our race engine (13.9 to 14 .2 ,steel body ,pan cage ) is a 1300 single port ,120 cam , 1.25 ratio rockers , 1679ccs thick wall slip in p&bs 044 cnc heads , 40 idfs ,15/8 header , light fly wheel. Not had any bearing wear problems , 6500 rev limit and 10-1 compression. 120+hp.No cooling though.

[Joel Mohr]

turbo it....

[Jim Ratto]

1.25:1 rockers, with bolt-together shafts, HD springs and swivel feet if you use rocker with adjuster @ valve end. Dellorto 34FRD if you can find them, with single-port manifolds. A simple 1-3/8" header with our without heater exchangers and a nice muffler, mechanical advance Bosch distributor (019 might work best, since it has less advance in it than 009 or 010- you can use more initial for off idle response), projected nose plugs, maybe a good CD ignition and powerful coil. The fewer tuning issues you have to overcome, the easier it will be to feel difference in a small cc engine. In other words, a smaller cc engine may present more "tuning snags" than a bigger cc one, simply because signal to carb(s) is weaker.
An early fan will pep it up too, but be careful.

[modnrod]

Build a F.Vee copy motor........

[Martin S.]

Nitrous! 

[181]

I´m slooowly building an engine for my early baywindow. Consists of following:

dual relief case with HVX mods and POrsche oil squirters,
CW 69mm DPR crank with stock weight flywheel and original VW lower pulley cut for a sand seal
balanced set of stock rods
AA thickwall 92mm cylinder set
NOS singleport heads with single hi rev springs, 1.25 rockers, stainless valves. CR on this engine will be 8.2:1 IIRC
Engle 100 cam with blueprinted Schadek 26 mm pump, original pushrods, CB lifters
cooling: all lower tins, industrial tins, 30HP style doghouse shroud with velocity ring added, and also thermostat assembly from an original engine
CSP stainless single quiet pack exhaust with header which clears all lower cylinder tin!
KAdrons rebuilt and rejetted by Kaddieshack with old style metal aircleaners and CSP centerpull linkage
ignition: I have a nice restored blue 019 but I also have a full EDIS set so I will see (said the blind)

This is my take on singleport engine maybe you can take some ideas. I think this will power my early bay microbus just fine. ¨¨

Jan