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been lazy with pics but will get some soon, 253 seems to be going down hill :/, screams all the way to 4500rpm, than points bounce, and some valve float, and has a strange 'fluffy' idle ,thinking carby, has a miss every now and than aswell, still chasing it, replaced everything. but still surprising for a little thong slapper
might throw a red 308 in it that i scored as we all know more cubes fixes everything,
than hopefully ill have another vehicle to drive so i can than take it off the road for abit and put the injected 5lt in once its built.

Now your talking. Make sure you fit the Bosch high energy ignition system to eliminate point bounce and other limiting factors.

that was the first thing to go when i had the hot 6 in it, but v8 elec dizzys are abit harder to find,

Charlescrown wrote:Don't like to say it but the 253 was a dog and didn't go. Stick with the 202 or go 5L.

I guess you haven't driven an original factory unmolested VH SLE 253 then, for a 253, they ripped, blew me away the 1st time I test drove one late 80's after rebuilding the qjet carb on it.
When the owner came to pick it up, I mentioned it ripped for a 253, his reply was yeah, I'm on my 3rd diff as a result, they used the shitty 6cyl 8 bolt UC carrier style diff
with 6cyl diff gears in them..

I later did some research on them, {A lot actually}, they had lumpy pistons {albeit a small lump} .020" shim head gaskets with the piston .020" down the bore, factory,
196 @ .050 square cam @ 106 lobe centers, no advance / 106 on both, hence why the 253 had a dual exhaust, factory, whilst the 112 lobe sep 308 had a single exhaust,
though the dual pipes both ran down the same side with a 2 in 2 out muffler..
The small advertised duration on the cam meant it still idled smooth as the overlap was minimal since the exhaust was 8deg less than the 308, which was 196 / 204 @ .050..

Mid 90's I had a mate rebuild a 253 & put it in a UC Hatch, put std L34 valves in the head, raised the comp a fair amount, he used 106 lobe sep camshaft, it put a few 308's to shame, used the original dual plane manifold, I re-graphed the dissy & tuned the qjet carb to suit..

The problem with most rebuilt 253s I've seen is they usually always ran too wide a lobe separation in them {since 99% of the time it's an off the shelf camshaft}, OK if you're still running a 2bbl carb & restricted exhaust like the red motors were...

Macca97 wrote:that was the first thing to go when i had the hot 6 in it, but v8 elec dizzys are abit harder to find,

Actually they aren't hard to find. Go to Supercheap's online store, or pop into a Bursons and order a brand new one.

i know Burson's sell them, but im a tight ass ahah, even though i get trade price

Don't touch the Chinese shit, better off with 2nd hand genuine Bosch. If you can't get that put Bosch module and pickup in Chinese housing, even then the weight mechanism etc is shit compared to genuine but will keep you off a tilt tray

HQ355 wrote:Don't touch the Chinese shit, better off with 2nd hand genuine Bosch. If you can't get that put Bosch module and pickup in Chinese housing, even then the weight mechanism etc is shit compared to genuine but will keep you off a tilt tray

I'll second that, I've even had some issues with new bosch modules lately, ended up pulling a second hand one from a used dissy, I'm suspecting even bosch has gone to the dark side like msd & many others..

Edit: Something else regarding this chinese poo I've seen when spinning it up on the vane dissy machine, the chrome tin cover screws with the curve & dwell.
Write down what you see regarding a curve & dwell with the cover off, then put the cover on & screw it down over the module & check it again, & have a WTF moment.
I'm guessing it's why GM used cast alloy on 99% of all genuine dissy's I've seen...
Though I have seen cases where it's OK with the tin cover..

I fitted one of the Chinese specials to a mates car and it went like a dog. Looking at the timing it retarded as the revs increased. I put it down to something in the module going haywire as the dwell extension was occurring so I fitted a Genuine Bosch module and bingo great from there but the build quality is extremely poor. Put together by 10 year old's with no quality control.

well im now running the red 308 i had lying around, little 253 dropped a lifter and wiped the lobe off the cam, so i stuck new bearings in the 308, gave the heads a quick service,
stuck an old active single plain manifold on it (i no bad choice for street) and a new edelbrock 600 carb, (no flat spot at all)

different ute to drive, still running the banjo diff, so ive gota be soft on the right foot