RS Motorsport :: Classic Speed Restored

Not allowed Steve

Fired it up today after resolving a few dramas with the starter motor and alternator. Promptly greeted with fuel pouring out the throats after I switched the fuel pump on. Tend to think one set of floats were a bit sticky as I only tweaked the level slightly. Restarted with some more advance on the distributor and it got progressively smoother as everything warmed up and no more fuel out the air horns.

Oil pressure is 70psi at 1400, going up to 90 at 3000. I think once the mixtures are set it will idle around 1200.(Maybe)

Seriously need to get some better ventilation. I'm fairly certain I shouldnt be breathing the Avgas exhaust

Fitted up the backing plate onto the carbs today. Took the manifold and carbs off the engine as it was the only way I could see to mark out the plate. Once the top and bottom stud holes were marked I very carefully used a 48mm gasket to mark the circles for the throats, then cut it all out with a stanley knife and a small wad cutter. Would have been nice to use a wad cutter for the big circles but my set aint that big.
HAving said that, the backing plate plastic is very thin, 1.7mm, easy to cut but it's a good thing the rest of it only weighs stuff all. I was looking at getting a pipercross backing plate to use as a stencil to cut the backing plate and I might still do that just for some extra support.

Getting some alloy bushes turned up for the alt bracket. Must be something slightly different with this block compared to the old one as I never had any problems with the alt drive but now it's not running in plane with the crank pulley.

Busy weekend in the shed. Mission was to re-fit the ignition system wiring harness which I had stripped out and set-up as portable to take to the engine dyno. Plans changed and the engine dyno is out and the chassis dyno is in and may happen Thursday/Friday this week. I could have left it as is to dyno but thought it may as well have a proper going over since the carbs and manifold are off.

Bear in mind the HI-6 was added overnight before a hillclimb. I wasn't sure it would do what I wanted so I put it in without cutting any of the crane supplied wiring and plugs and that's how it ran for 3-4 events until the head gasket gave up. It was all taped up and safe enough electrically but lets face it it was just ugly.

So i de=mounted the unit off the LH cowling and fitted it up to an adapter plate. I've put that directly under the dizzy module and then basically started cutting all the now excess wire and weather proof plugs. I mounted a DC busbar onto the plate and use that to apply +12V to the cylinder select and rev limiter function wires as well as the main ignition circuit and power to the XR3000 module. This is far more elegant than having crimped piggy back fittings all over the shop. Both modules are now earthed properly to the chassis also instead of meters of wire back to the battery.

Engine/gearbox coming out of car again due to an oil leak from the gearbox between the maincase and extension housing. I could drop the gearbox support and just take the gearbox out, however I also have an engine oil leak either from the rear seal or from the sump gasket. Because of this I havent been to the dyno yet, didnt want to wreck the clutch plate with oil. So my cunning plan of doing a chassis dyno instead of an engine dyno has pretty much fallen into a hole.

I know that feeling mate... keep on it, it'll come good in the end.

It'll either be the sump at the join with the hump seals or the rear cap mounting faces
Is the sump steel or alloy?
The rear extension make sure you use a paper type gasket as it will fret between the two and sealant will leak

I'm still not 100% convinced its leaking through the gasket, my first impression was the extension housing had a hairline crack in it, which I thought i could see open up when I pointed the heat gun at it for while. I drained the oil and cleaned it with brakekleen then pushed some 2 pack alloy putty into the suspect area. Put the oil back in and voila' it still leaks. I left a drip tray under it for 2 weeks for about a tablespoon of oil so its not major but who wants gearbox oil on the track.....not me

Danny your probably right with the sump leak as the crankshaft scraper ends dont tag into the lugs on the half moon seal properly. I must have missed a spot or not had it clean enough. Its a tricky thing as the scraper has to be dummied up to make sure its in the right spot, then take the sump off without disturbing the scraper and apply the rest of the sealant and button up. First time I got it wrong and N0 3 rod was fouling on the scraper(dead stop turning crank by hand). 2nd go got it right but now its leaking in there somewhere behind the bellhousing

That's the reason I'm not a huge fan of doing the scrapers that way the other thing is will it wont have as much tension on the hump seals because of the increased thickness of the scraper

Three Bond?

Since there hasn't been any posts for a bit I thought I might do a bit of an update on the Cosworth build. Its been a crazy ride the last few years with finances and job redundancies but the racecar is back together and been to the dyno. Its made good power and torque but not massive. As a mate pointed out its equivalent to his Sierra Turbo engine and my sports sedan is a 100kg lighter than his so I'm confident it will go well. How close I can get to the 2L class record at Collingrove remains to be seen. State titles next weekend!!

Two twenty horse?

122KW at the wheels. 170NM torque @ 6750RPM. Was aiming for 200BHP. I probably should have taken Danny's offer to weld the chambers as I just couldn't build enough compression into the head and ended up with 10.5:1

Yeah it would help.