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Discussion Starter · #1 ·
Your car looks smokin', about a year ago I was going the N/A route like you are . When I figured the cost of a cam and other performance goodies I decided to go turbo much more power and fun . The 3.9 will give you that extra jam .
Look here at this website it has some good mods his 0-60 time is a tad exagerated .
http://www.digiserve.com/dswartz/Datsun/ . You can also adjust the spring tension on the wheel in AFM to give it more snap, index you plugs, K&N filter, sdvance timing and toy with advance, MSD 6A (I have it gives better throttle responce and low end torque smoother running), header, 2.5" exhaust, larger TB port matched . In the Z a total of extra 10 hp goes a long way . I am shooting for an extra 100hp with my turbo .
 

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Discussion Starter · #2 ·
Experts - Here are my current engine problems

It's running rich and I get little backfires at low load like when I'm idling down to the house in 2nd gear, It's idling too high (1,200rpm) even with the Idle Adjust screw turned all the way in. I have all new hoses and vaccum lines. I have blocked off the BCDD, I have blocked off the Air Flow Regulator. Timing was set to factory spec, but I retarded it some due to pinging under high rpm (5,200+) under load (flattops with N47 head)

Any suggestions on what to do?
 

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Discussion Starter · #3 ·
Sounds Like...

Hi Steve,

Nice car. I would adjust the air flow meter (AFM) first with the throtle position sensor jumped as indicated in the manuals for idle mixture adjustment. This made a huge improvement in my 78. To pass emissions, I had to back the air bi-pass screw on the AFM untill it was about to fall out. I re-adjusted after it passed. My first thoughts.

The 3.90 should make your car launch like a rocket. Flat tops in the N47 was going to be my rebuilt untill I found a turbo setup. The turbo is complete new grounds for me, but it's something I've wanted to try for a while.

Good luck and Happy tunning,

Rod
 

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<b>Good Info Rod</b>

Yes that is very good information . The throttle position sensor can make a huge differnce in a cars behavour . My brothers past Celica was increadibly gutless below 3000 rpm, that was because it was showing idle for quite some time . Take an ohmeter and put it on tps the reading should change just as the throttle is opened . You say you blocked off air flow regulator, got to a junk yard and get another . I tried blocking it off but still didn't quite work properly . Now I would say the high idle is from a torn boot or hose between AFM and engine . If you have not already changed these rubber parts I would recomend doing so . Go to store and buy a roll of vacuum line replace every last one, it's cheap and vacuum lines will keep cracking again and again . Take the AFM out and inspect these boots . I bet they are cracked or have holes in the bellows part of it . I have yet to have a problem with my actual fuel injection . It is usually rotten rubber that gets you every time or the stuck air regulator . Spray starting fluid on parts to check for vacuum leaks, if rpm picks up you have found the leak . If this fails clean the grunge out of all connectors . I am quite sure you have a vacuum leak and you are running lean which will cause pinging, and the characteristic back fire . Do this then write back .
 
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