Throw away that header.  Get a Nissan Motorsports or Stahl with 1 5/8" primaries.  Upgrade the exhaust to 2.5".  A cam with more duration (around 270) will also help.

Edited February 3, 20169 yr by John Coffey

I highly recommend the distributor from 123 Ignition.  It is fully digital and therefore fully programmable in terms of the advance cure that you want.  It has a USB port which you connect to your PC and then use their software to define the exact advance curve that you want.  If you don't like the curve or want to try something more aggressive, it takes literally 2 minutes to change it.  One of the best upgrades I have done and a lot better and more flexible than the Mallory Unilite that I ran previously.  You can find more info on it here:

http://www.123ignitionusa.com/

Mike.

21 hours ago, gnosez said:

R180 LSD in a 3:54 diff? And coupled to an "A" tranny - big gap between 2nd & 3rd as opposed to a "B" ZX tranny and a higher ratio diff.

Im guessing you mean a type "B" transmission out of a 280Z or a 2+2 which is commonly known as the Wide ratio FS5W71B. The ZX Close ratio is a nicer spread, but you will find first is very tall and slow off the line it you couple it to a 3.54 diff. They work better with a 3.70 or 3.90.

30 minutes ago, EuroDat said:

Im guessing you mean a type "B" transmission out of a 280Z or a 2+2 which is commonly known as the Wide ratio FS5W71B. The ZX Close ratio is a nicer spread, but you will find first is very tall and slow off the line it you couple it to a 3.54 diff. They work better with a 3.70 or 3.90.

I don't know if it is an A or a B transmission.  I ordered a new factory 280Z 5-speed using the factory part number somewhere around 1990.  I was told it was the last new one in the country at the time. 

1 hour ago, John Coffey said:

Throw away that header.  Get a Nissan Motorsports or Stahl with 1 5/8" primaries.  Upgrade the exhaust to 2.5".  A cam with more duration (around 270) will also help.

Thanks for the advise.  But I have already spent too much money and to many decades on this car.  It's time to drive it the way it is and then maybe sell it.  The next owner can upgrade the cam and exhaust system as recommended.  My goal was to build a Z that was higher performing than stock and very streetable.  I should have it back from the shop next month. 

3.54 with a 1978 5 speed is the factory combination.  The 2-3 gap is noticeable at times with the weak factory engine, like if accelerating up a hill, but not a huge deal.  You probably won't be able to feel it unless you're racing.

Did you send your L26 to Rebello?  Is it still a 2.6 liter or did he increase displacement?

12 minutes ago, Zed Head said:

3.54 with a 1978 5 speed is the factory combination.  The 2-3 gap is noticeable at times with the weak factory engine, like if accelerating up a hill, but not a huge deal.  You probably won't be able to feel it unless you're racing.

Did you send your L26 to Rebello?  Is it still a 2.6 liter or did he increase displacement?

The block was machined and rebuilt locally.  The pistons are 0.004 over, which if I remember correctly, was the next size up from stock that Datsun offered at the time.  The head was sent to Floyd Link to be rebuilt and set up with the reground cam as noted above.

Edited February 3, 20169 yr by fixitman

Just for the info. The "A" transmissions in the US were 4 speeds and they changed over to the "B" somewhere in August 71.

The A transmission had a three piece housing with detachable bellhousing

The B transmission had a two piece housing with integrated bellhousing.

 

I had Rebello in mind for some reason.  E88 head?  Did Floyd do any port work on the head?  There could be a lot more questions.

Just learned something about Floyd Link - 

http://www.stevelinkracing.com/#!parts/c1k7w

http://www.datsun.org/fairlady/BRECrew.htm

I edited my earlier post regarding dizzy and other related items.

As to Eurodat's tranny answer, it is my normal inclination to call the early USA 5-spds (77-79) an "A" version and the 80-83 a "B" tranny. The 3.54 diff was stock and that was why I asked if it was an LSD as that would of course not be a stock/OEM version. Available? Yes. Stock? No.

I just use the factory labels.  Pictures from 1971, 1973, and 1978.

2 hours ago, Mike W said:

I highly recommend the distributor from 123 Ignition.  It is fully digital and therefore fully programmable in terms of the advance cure that you want.  It has a USB port which you connect to your PC and then use their software to define the exact advance curve that you want.  If you don't like the curve or want to try something more aggressive, it takes literally 2 minutes to change it.  One of the best upgrades I have done and a lot better and more flexible than the Mallory Unilite that I ran previously.  You can find more info on it here:

http://www.123ignitionusa.com/

Mike.

I am also considering this upgrade and I think it makes sense for a street car.  When I asked Rebello specifically about the 123ignition he stated that he saw several of these melt under race conditions and recommended the ZX dizzy.  The ZX dizzy is significantly better than my 260 ignition but I think theres still room for improvement.  The more I live with this 3.0 motor the more I realize that street driving is more demanding on how well a motor runs.  You dont need to start a race car and drive it to work cold, and you dont need to run a street car at WOT often.