hi guys, im not a regular here by any means so be nice to me!

i had this idea of supercharging the a15 engine which i have sitting here (out of a vanette). what work would i have to do to the engine to achieve a modest result and still be reliable? its not going to be a race engine or one that is driven at very high rpm, probably wouldnt ever see past 6000rpm.

my initial thoughts were a toyota sc12 or sc14 supercharger onto the engine with a suck-through setup. decompression to about 8.5:1 ratio. general rebuild of the engine. camshaft to suit mid range power. i havnt thought of a carby to use yet. at this stage i dont intend on intend on intercooling but if i do then it would just be a small unit off a toyota starlet turbo or something similar to that.

not being a high revving engine would i still need to go for double valve springs and engine balancing and all that expensive stuff?

ive probably overlooked heaps of stuff! thanks in advance for your advice.

NB: this engine would be going into a morris minor so it cant go any longer than standard and headers would have to be custom made

if you use the search button on the side and you will find that a few people have done what your looking at doing. many people have also turboed a series engine with great success. i did notice you were looking at running a suck thru system which means you cant run a intercooler, you can build it with double valve springs ex....ex.... but you dont need to especially if you dont plan to do work above 6 grand (not likely once you have boost)

there is actually a supercharger set-up fro sale right at the moment and i think he had it in a morris minor uteclick here for the ad

send him a message i'm sure he'll share his knowledge with you

Supercharging is a great idea. My advise is, fit dual valve springs. Fit the biggest can you can. Just run a head saver shim to lower the compression. (DONT use two head gaskets) And lock your mechanical advance mechanism, and run all your advance static. Totyota blowers work fine.

by mechanical advance do you mean the vaccuum advance on the dizzy?

No I mean the mechanical advance operated by centrifiacal force inside your the dizzy beneath the baseplate.

ok, i havnt had a dizzy apart before, last datsun engine i rebuilt i left the dizzy alone.

will the engine detonate if that isnt locked?

do double valve springs damage any other parts in the valve train if all else is standard?

do you think i should change the camshaft or will the standard one perform fine?

thanks for your help aye, good to have some informed people around me!

yes it will detonate if you dont ajust the dizzy..... a boost build can be done a few ways all depending on what your budget is. i recomend doing it right the first time and not have to rebuy a better product when the original cheap part breaks.

mechanical advance can be tested by holding the bottom cog of the dizzy and trying to turn the rotor button.

if you pull the base plate (that points mount to) out of the dizzy you will see how that works..... and a bit of weld so that that doesn't work anymore

better to get a dizzy modified for boost retard

some a-series came with double valve springs so that is not a problem

i was under the impresion a standard cam was more suitable to boost application than a "big" cam but thats not really my expertise

another thing to consider is fuel delivery but that shouldnt be too difficult with a suck through

the other thing is getting the stronger gearbox and diff options

stock compression is great for a street car... and if you dont want over 10psi boost then it is not necessary to de-comp the motor at all

with my setup i had a worked cam, double valve springs and a head shim to lower the comp. i ran a 32/36 webber carb. it ran ok but it ran at its best when it was driven at higher rpm's around the 7 thousand mark or higher. i was only running 5-6 psi. with the dizzy i didn't do any mods to it. all the i done was insert the hose back into the carby where it originally came from since i had a suck through system. and i found that it had to be constantly run on shell v power fuel. any thing less and it would run like crap and ping of its head. hope this helps a bit.