madkaw

The 123 ignition could help with performance and to help pass emissions - IMHO . A fully programmable ignition curve would allow a more aggressive power curve without giving too much vacuum advance . Your engine/ head combo is not the greatest for performance . Added compression would make a stronger case for adding a programmable dizzy . Cheap way to add a little power is to advance the cam to hole 2 or 3 . This would add noticeable power/ torque down low . Once again this would be better if you had full control of ignition . A cam and programmable ignition would be best bang for buck

Can you guys get away with a 123 dizzy ?

I don’t know guys - I’m not going to try and figure out Nissans engineering , but the larger capacity of the piston assembly in the BMC needs to go to the front brakes . My intention now is to get Classic Tube the correct info for when folks order lines . I made them aware that the early BMC’s are not readily available and most would be going to a later BMC - which means they need different lines than what’s in the early kit .

Why do I think F goes to the front lines ?

Whatever is done the F of the MC should go to the front brake lines- and R should go to the rear lines - regardless of the reservoir size .

Yeah I hate tuning my stroker with a laptop - it’s so boring

More than likely they should both be n54

Okay- I got the word from my parts expert . This probably old news or non-news but I’ve just ran into this and was having difficult time finding the correct info 240z 69-8/71 used first series of BMC - E4602 plumbed F-R 8/71 - 6/72 uses the E 8702 series BMC - it is plumbed R-F 7/72-7/73 also uses the W8702 but the safety switch is moved so it’s plumbed a lot different . If anyone has contrary info I’d be glad to hear. If not I am going to notify Classic Tube

If the larger reservoir is up front then more than likely the front brakes worked off of that side. So the lines to the warning switch would have to run differently - correct . The early lines stayed separated where as the later the lines cross - because the warning switch stayed the same ?

The MC seals are all oriented the correct way. The Nissan unit matches up with the aftermarket fine - see pic . So I reached out to Classic Tube since it seems their kit doesn’t have the correct line routing MC to warning switch correctly . They show 3 kits by year . The first kit supposedly goes from 1969- 6/72 . The second kit goes from 6/72 until the 280z?. Am I wrong that the earliest BMC had front and rear oriented differently and thus had the lines routed differently to the warning switch? If so - when did the MC change ? Classic tube wants to get this right also .

Round

That IS the issue . It seems that EPDM O-rings are what’s best for brake fluid . Then you need the exact size . I believe the seal need to be 6x10x2

You are correct - I should use the proper name .

Not a very good pic but you might be able to make out the busted O rings on the piston . I’ve ordered some O rings . I will “ rebuild “ the prop valve and reinstall the MC with the lines routed properly

Well I guess I have my lines crossed . I replace the originals with SS - but the replacement lines were routed the same way as the originals . I contacted my Datsun part expert and shared a pic that helps . The F&R lettering on the BMC didn’t seem to correlate with the plumbing of the proportioning valve . Still not sure that would cause the transfer of fluids though

There is a transfer of fluid happening between reservoirs so it is overfilling - that’s the issue

1972 with all new brakes . Master cylinder is a NABCO , or whatever is being sold by Nissan - but made in Japan . I am losing fluid but in a strange way . After a long period of driving I check the MC and the front reservoir is low while the rear is full to the top . I have brake fluid oozing out somewhere from the rear reservoir . Not sure if it is somehow getting pressurized and coming out the bottom or what . I’ll have wetness around the band clamp and around the MC body . The band clamps are tight . This is driving me nuts . I’ve never read of this situation . The front brakes are upgrade with the S12 calipers .

Another reason to get to HB ! Lol

Another job that I utilize the dead blow is valve adjustments. I probably should make a video now because folks will be wondering . Lol

Yes- please folks -invest in a good dead blow hammer. It’s great for such jobs as this . A 3lb dead blow is a useful tool and save your hands . Curious is why you didn’t just drop the car on cylinder blocks to weight it? It’s tight , but you can slide under there if all you are doing is smacking them tight . Just asking - thanks for the video Merry Christmas

I’ve been working on a 2/72 and the owner wanted to keep it original . I was getting a battery drain . The VR looked new. When I plugged it in it would click and cause a drain . Ordered another one and it did the same thing . So now I think it’s the alternator. Took it to an alternator shop and he said it was fine . He also said he had an issue finding a good VR - period . He could a box of them and they would all test bad . I got rid of the VR

Yes - I just went and looked . Only two screws at the top of the frame . Wondered if folks were glueing them in - in order to facilitate a seal .

Curious if these can be made to work on the early models ? I saw another sale ad that said they would . These were meant to deal with wind noise I imagine ? I’ve seen ads for the bottom front seals for the quarter window , but not the top . https://www.datsun-garage.com/collections/datsun-240z-260z-280z-s30-weatherstrip/products/reproduction-front-quarter-window-weatherstrip-1974-78-260z-280z

This basically how I did mine - thanks Cliff. I think the speed bump tang is important . Floats seem more consistent .

My 9/71 has vertical lines