A14 Mild street performance build

[sick620]

1 hour ago, Tom1200 said:

First; I run all stock Nissan components in the bottom end of my A12 & A15. I rev them to 8600 rpm all the time without issue.

 

I'm using a Delta 280 cam and the powerband is 4500 to 8200 RPM. I'd check with Delta bit for the street I'd go with the milder of the two cams.

Tom, can I run the Nismo brand dual springs with factory collets and retainers etc.? I see Nismo had part numbers for them but I cant find any for sale only the springs themselves. I also cant find A series spring anywhere on the isky site, but the Nismo ones are available on eBay. Nismo recommends you use the Nismo collets and retainers with the Nismo springs, but since they are not available anywhere I'm wondering if I can just reuse my factory stuff.   Thank you for all your info. 

Edited November 4, 2022 by sick620

[Stoffregen Motorsports]

Isky springs - https://iskycams.com/shop/index.php?main_page=product_info&products_id=2134

 

This jives with the info on the http://datsun1200.com/modules/mediawiki/index.php?title=Valve_springs site.

[sick620]

8 hours ago, Stoffregen Motorsports said:

Isky springs - https://iskycams.com/shop/index.php?main_page=product_info&products_id=2134

 

This jives with the info on the http://datsun1200.com/modules/mediawiki/index.php?title=Valve_springs site.

the springs you link show they are for an alfa romeo? 

[Stoffregen Motorsports]

I took the part number off of the 1200.com site and entered it in the google search bar. That's what came up. Look at the measurements as compared to the specs on the isky website. They are the same.

[datzenmike]

Duration specs by cam makers are universally measured at 0.050" valve lift. I doubt Nissan did this.

 

L and Z series are 248 degrees but could they really be more like 220???? Has anyone ever degreed an L cam???

[sick620]

7 hours ago, Stoffregen Motorsports said:

I took the part number off of the 1200.com site and entered it in the google search bar. That's what came up. Look at the measurements as compared to the specs on the isky website. They are the same.

Oh ok I see what you are saying, 1200 wiki shows those spring specs being for a holden? and they are listed under the "possible" section.. I wonder if they will work.. Maybe worth the try at half the cost of Nismo and says they can see 10k rpm damn...

 

So I get the biggest cam from delta, arp rod bolts, these springs... rebuild the block with the new .030 over pistons, new bearings... Basic head port and polish. New valve guides... Re use valves (heads in great shape 120k miles)...  nismo gasket to bump compression a bit..

 

should I get a valve job or just lap them? seats look to be nice... 

 

will I need to buy any new valve train parts IE rockers, push rods etc.? I don't know much about these push rod motors anything I need to replace as far as wear items since I'm running a shiny new cam? 

 

any other recommendations? I don't want to rev this thing up to 8500 and blow it up. 

 

any value in gapping rings a bit bigger since I'm sure Ill be introducing a bit more heat revving it up higher than a stock motor don't want them to expand and crack a piston. While on the subject and chances are I won't do this but the idea has been rolling around in my head a while, but can one of these motors handle a 35ish shot of a wet nitrous system? I feel like that would be a pretty fun set up being able to cruise it around at low rpm getting reasonably good mpg, then bring it up to 130ish HP on spray for short bursts when I want to rev the crap out of it.. I'd do it as safe as possible with step colder plugs, timing retard, only spray at WOT. Not a lot of information on spraying the datsun motors, but I've always thought it would be a fun adventure. 

 

 

[datzenmike]

Gaping for hot street/strip should be fine multiply the bore diameter (A14) 2.9944" X 0.0045" = 0.1347" Make it an even 0.014"

 

Moderate turbo/nitrous is 2.99" x 0.0055" = 0.01646" so split the difference and say 0.015"

 

Still have to work out the second ring

[Stoffregen Motorsports]

Mike's right about the gap. I gap them a bit tighter, but it can depend on the type of ring being used. Modern low tension chromoly rings get .003" per inch of bore.

 

I would definitely have a three angle valve job done by someone who knows what it means to have a three angle valve job. The contact area of a three angle valve job should be about .050" for maximum performance.

 

Stock rockers, pushrods, main cap bolts, cam bearings, oil pump, timing gears and chain are all good. Main and rod bearings should be tri-metal, no exceptions. Hit the main bearing saddles with some emery cloth to remove the burrs from the edges of them. This helps not get scratches on the back of the bearing shell during bearing installation. Also, radius/chamfer the oiling holes in the main saddles. Deburr them too.

[Stoffregen Motorsports]

Somewhere I've got pics of a couple killer A motors I built when I was young. Guys raced them in SCCA GT5 and in DSR. The DSR motors were 1000cc, so we used a custom billet crank. They would rev well past 10K. All of these motors had dry sump systems and custom valve covers with no oil fill or breather holes. We got them from TDC, which is probably not in business anymore.

 

The pics are probably in the same box as the pics of your Toyota blue 510.

 

[Tom1200]

I haven't been on the site for a few weeks. The link to Isky appears to be the correct part; from memory 455D is the correct number.

 

As for the collets I've always used the stock ones.