Page 1 of 1
620 Header
Posted: Sun Sep 29, 2013 10:27 am
by blueghost510
I'm looking for a header for a 79 Datsun 620 (two wheel drive) pickup. If you have one and interested in parting with it.... can buy or trade for other 620 parts.....
Re: 620 Header
Posted: Sun Sep 29, 2013 11:16 am
by datsunmike
Then you really need a round port design for your W58 head. All '77 and earlier L heads were square port. A square port will barely work on a round port head and if a cheap design will be even worse. Has to be for a truck to clear the torsion bar.
I must say that unless you are running a much larger cam and larger or multiple carbs with the head ported a header is a waste of time and money that could be spent on much more productive things on your truck. The fact is that the stock exhaust is pretty good as is, and so a header doesn't improve on it much. 99.999% of the time you drive below 5K so there is nothing to notice. Cost is $50 per HP gained above 4K. Time spent? I put a header on my 521, the 620 would be similar. Took all afternoon, had to remove torsion bar for clearance to get it on, a new intake/exhaust gasket, loosen the motor mount and jack motor up, cut up a perfectly good exhaust down pipe, luckily I didn't break off a manifold stud. (a very real possibility) Gave up and finished it the next day. Let me say that I was so disappointed with it that I would have put the original manifold back on and thrown it in the ditch if I had had a welder and had another day and a half to waste on it. It ran absolutely the same except it was...annoyingly loud, the flange to pipe bolts needed tightening every two weeks, (and leaked) wasn't a great fit in the first place, (had to dent in a pipe to clear steering column) and was rusty as fuck in 6 months. Don't make this mistake. This is something that is only useful on a race prepared or modified motor that can actually use it. Even $50 used header is $500 worth of trouble.
If you do get one, buy new and spend $250 or so. This way it will fit right and be a better quality that doesn't leak around the gasket. Expensive ones are usually nickle or ceramic coated and will, with care, last maybe 5 years.
Re: 620 Header
Posted: Sun Sep 29, 2013 1:38 pm
by blueghost510
LOL... Thanks Mike.
Stand corrected, I need a L-20 Exhaust manifold for a 79 Datsun 620. Mine is cracked and has already been repaired once.
Figured since I was pulling the exhaust manifold off anyway I would throw a header on... Anybody have on laying around and interested in parting with it?