I tuned the carby on my turbo setup myself - via on road testing and a WBO2.

Idles at 14.7:1 and tapers down to 12.5:1 at peak torque (ie max cylinder pressure) then revs out to 13.5:1 so this is almost ideal for a turboed car's fuel air curve. Alas the problem now lies in that this is good for power but unlike EFI the carby wont lean out under a low load situation...meh - she's not a daily.

Also because I'm not using ur typical SU my carbie flat slide is mechanically opened so just pulling out from a dead stop if you just flatten the pedal the car picks up until the accelerator pump shot burns off and because the enigne RPM isnt enough to suck fuel its self at that point it leans outs. This isnt a issue because If you were to launch the car you would do it in boost and crusing wise you dont open the throttle that fast - anyway, the pump shot would need to be 4 seconds long to over come that and would kill the engine when heel toe downshifting. However on road its awesome. Fuel air ratios are great - because I machined my own carbie needle, jets and emulsion tubes (cant buy the right ones to get the fuel air needled for a 1.2L turbo motor to be spot on).

Its still a work in progress as Ive had it 20psi with more timing but backed it off to 18 psi and 25 degrees.

I've sorted the jetting but I still need to install my bigger radiator (its a alli 300zx radiator squeezed inbetween the chassis rails and pokes up 50mm above the radiator support pannel). So its pretty much the biggest you will fit in a B310.

Also I will do a write up once I'm finished but I still have to like mentioned; install the radiator and Ive got a gilmer drive to go into it aswell. Then I will look into a stud kit for the head and a cooler thermostat!? Maybe.

By stock gaskets I mean just like the normal paper type ones with the steel rings around the cylinder bores however I got an ACL one and I just call that a "stock" one - sorry for any misleading info.

Really you wont just blow a head gasket untill the head lifts (ie too much boost or warping from over heating) so a good quality paper type headhgasket should be fine - but I'm looking at getting a stud kit for the head so that it wont lift.

Speaking of which; is there that much gain of a stud kit on a A series motor because seeing as the head bolts arnt torque to yeild I'm thinking that torquing them another few Nm wouldnt hurt? Would it?

So my stock A12 running 25 degrees timing and 18 psi is a ticking time bomb? I dont think so. It has the stock head gasket but I am running water injection (not that really helps the head gasket issue).

Properlly installed head gaskets should hold up quite well.

PS - 18 psi at the inlet runners; not straght off the turbo.

You must feel so proud...go buy your self a beer.

Jeez the fuel air goes on the tour de engine bay before burning lol.

Turbulance much?

Hi,

For my turbo build I was thinking of getting a larger radiator. So far in my Sunny (1979 B310) I've got what I think is the stock radiator (32mm core) and the largest one I can easily fit would be 550 long, 500 high and up to 75mm thick (core wise).

However, looking around ebay they seem to be long and not tall enough, tall enough and too narrow or the right size but use 32mm cores?!

So, is there anyone out in Datsun land that has a different radiator in their B310? What car did it come from?

PS - Im after a different radiator in search of better cooling, not for a clearance issue on parts etc.

Hi,

I was wondering what do people use to seal the flanges on the turbo.

Any sort of flamable sealant is out of the question as I am running a wideband and $100 a sensor (Bosch LSU 4.2) so NOT fouling it is my top priority.

However, my research returned that sometimes no gasket is used as the school of thought is that a slight leak is better than blowing a gasket, sometimes grease is used that burns into a carbon gasket (not O2 safe I presume) another thing to use is RTV's and other sealants (some are sensor safe but who kows how safe) also I dont know a liquid sealant that works when the turbo glows either.

This leaves copper gaskets, annealed copper is good but even on flat flanges I dont think it will compress good enough due to the large surface area. So I was thinking of annealing copper wire and bending it to make like a copper o-ring that will compress good.


Untill I find a good solution I can just get by with no gasket I guess as all the flanges are linished flat.

Yeah but then you have to pull the sump... lol I just want to avoid screwing with the motor until I rebuild it.

How would you seal the bolt holes then? The gasket will seal the pipe area but teh nuts will leak.

Good idea, that way theres no swarf and extra meat for the metal tek. Time to machine some spikes and make some test holes in some scrap.

This setup combined with the right sealant will do well as a permanent setup I reckon.

Hmmm, thanks for the heads up...I guess?! lol

Already have a new clutch in there when I brought it.

Can you elaborate more on...

"...using an oil pickup as the mating flange to the sump. Then you get a decent diameter return line, and a nice flange with two bolt holes in it. You just cut off the filter end, and put a swage in the tube to help keep the hose in place..."

So you mean cut it down so you essentially have a flange with 2 bolt holes and a pipe (~2" long) to hoseclamp the return hose too? How to you attach the flange to the sump? 2 Tek screws and sealant?

Which brings me too this...

I mocked up the return line and returning it to the timing cover will work but there isnt enough high difference (fall) for the oil so draining abilities will be poor. So I will go to the sump simply to because its more main stream in turbo setups AND to aid drainage.

I reckon I can make a punch and punch a hole in the sump, make a flanged tube as mentioned before and locate the bore over the hole, spot though the holes with a drill, remove the flange and drill holes to suit a tek screw (use a greased drill to minimise swarf into the sump) instead of drilling with the tek screw.

Now assemble the flange to the sump with loctite 515 on the flange face and use loctite 515 on the tek screws to seal the threads.

Hmm, that could almost do as a premanent solution!? What do you guys think?

Worst case is it only holds up until I rebuild the motor which in that case I will TIG on a BSPT boss.