L20b swap with a few questions

[Eomund]

Hey all. Just picked up a rebuilt l20b that I'll be swapping in my truck. I'll take some pics when it gets into full swing.

 

I'm thinking about picking up some performance headers. I'm seeing short and long headers and I'm not sure what I need.

 

I've done some reading and the swap looks like it'll be a cake walk. Are there any real differences I'll need to watch out for?

[metalmonkey47]

Headers are useless on a stock motor. It would take a lot more then bolt onts to see any performance gains.

 

With my shorty header on my L20B, I lost midrange power and torque. 

[Eomund]

Is the back pressure that low on them?? ...Wow thats dissapointing. I wanted to do it for looks more than performance honestly. But these don't have enough torque as it is. Losing any would suck.

 

Either way which one would I need If I decide to go this direction? I'm not sure if one is direct bolt on and the other isn't.

[datzenmike]

I put header on my L20B 521 back in the 70s. Will NEVER EVER do that again!!! They don't fit, they leak, they come loose, no one can see you have one when driving, noisy, floor got hot, Started Sat morning figured I would be bombing that afternoon... mostly finished Sun night. Had to remove driver's torsion bar and motor mount to tilt motor over to fit it. Cost me $89 in 1978 dollars!!!!! for two days of aggravation and a hour every month tightening up the collector gasket. Expected big horsepower increase and ran exactly the same. Performance parts companies sell to young idiots like me who want race car parts on street cars.

 

Other than weight what can a header do that the stock exhaust can't...

 

[Guest 510kamikazifreak]

Three words

 

 

Dont do it

[metalmonkey47]

Everything Mike said I agree with 100%

I'll retain the shorty header for my LZ, but it's a mildly high compression and FAR from stock, and may be able to utilize the extra exhaust flow. Time will tell. For stock, a nice stock emissions free manifold is the way to go.

[TENDRIL]

yep stock 

[racerx]

had 3 datsuns (2 wagons and current 510)..friends had headers on them and could not tell difference as far performance.  Similar set-up mainly stock.

 

But they did complain that they came lose a lot. Install a nice muffler like magnaflow or dynamax...how much HP do you think you will gain with header?  Don't make the pipes bigger than 2"..save your money for other things.  Good luck.

[Dawa]

mike was already up in here givin his schpeel (this is a weekly question)

 

hainz will come in here talkin bout if you do get one, make sure its from company XXX,

that the flanges are solid/stout, and that you ceramic coat it or else it will start corroding immediately.

 

mike kinda touched on the fact that the L20Bs are taller than the 1.6/1.8, so some modification

is required to either the exh pipe, firewall, etc as well as it already being a tight fit

 

long  story short, spend your money elsewhere

[Eomund]

So the L20 is taller... Will that be an issue for the fit of the stock manifold?

[TENDRIL]

no, but i think the best stock one you can get if you can find one is the L18 sss stock mani, 

[racerx]

of course this will come up over and over again.  You have people that just got into the Datsun seen and they will want more power for their 4 cylinder. Other questions such as the distributor, coil overs, lowering their cars, radiators or should I put a elect. fan, converting 4 speed or auto into a 5 speed, head, carburetors, seats, type of paint, shipping thier cars, type of rims, ...and so on..juts a matter of time..and people will chime in because of their experience and want to help someone modify their car or help them save money.  After this is what this site is for. :thumbup:

[Eomund]

no, but i think the best stock one you can get if you can find one is the L18 sss stock mani, 

Thats handy cause the current semi broken motor is an l18.

 

And I'm well aware that the perfermance gains will be minimal at best with the performance headers being as this is anstock motor. My reasoning would be 90% aethstetic. The fitment issues are troubling at the worst for me. I've dealt with worse. Honestly, my biggest concern would be the possibility of losing some torque.

 

And I do want to thank you guys for your feedback.

[TENDRIL]

the intake mani sits right above the exh. mani. so you will only ever really see the #1 cyl tube and the lower half i personally like the look of the stock exh. mani. to me they already look like headers.

 

 

and if your not on a strict budget, and you want the mani to look good, sand blast it and put some high temp on it or chrome it..