83 Spider Exhaust Manifold

[rictorg]

So, we got the young lady to the shop, and started sniffing around. One of the known issues was an exhaust leak, and we traced it to a smallish crack in the exhaust manifold.

Seeing as this is something I'd like to fix, I understand I have several options. I can...

(a) weld the crack, thus repairing the stock manifold
(b) replace the manifold with a used but structurally sound one
(c) replace the manifold with a new one
(d) take this opportunity to replace the manifold with a header, thus falling into the rabbit hole of performance upgrades.

My question to the enthusiasts more knowledgeable to myself (which is, well, nearly everyone on the board ) is which of the choices would you select, why you'd select it, and what effect will it have on reliability, performance, and ability to have it smoged in the future (fortunately, I'm not required to do so currently or in the expected near future).

[Zunige]

Specifically in a 1983 Spider, I'd go with headers - hands-down! The manifold of the series 3 is purposely restrictive, and this will have a positive effect on performance and power efficiency. If the car still has the OEM cat, I would also suggest that when the time comes (that could very well be now) you replace it with a modern unit.

I would also encourage you to do a search... There are several threads about perfromance covering this subject, and some are pretty long, so take your time. For starters, and rather than trying to repeat some of what I've written, I'll point you to this post and this thread.

Best regards,

[lasajef]

If you decide to go with a stock replacement, I have one off of an '84 that is in very good condition and a reasonable price.

[tmrobinson23]

Depending on your budjet, as noted above, the headers are the way to go hands down. We (my wife & I) have an 87 that we put headers on and it gained quite a bit of power with no other mods.

If you really want or need to keep it stock though, I have the stock manifold from the 87 you can have for the cost of shipping. Some parts are just not worth holding on to if someone else could use them. Everyone at alfabb has been very kind, helpfull and enjoyable to talk with, so I'm happy to give back to help an alfista out. If interested e-mail:
tamaquaadam@yahoo.com

[Geezer]

As another option you could go to the '71-'74 2 piece manifold and not put up with the aggrivations of a header.

[bianchi1]

..i agree, headers..long turm they will cause loss problems..no more cracking...as cast old replacement manifold might do down the road...but if the manifold is cracked..how are the motor mounts, and the mounts onder the transsmission, are the saging,, that helps crack the cast manifolds,,,on the motor mount..go for paul spruel mounts... lots of folks say they are better..soo far i like them...but if you replace the motor mounts..go for the exhaust mounts onder the tranny. if they are soft, or worn out..

[Zunige]

Quote:

Originally Posted by Geezer As another option you could go to the '71-'74 2 piece manifold and not put up with the aggrivations of a header.

[rictorg]

My buddy suggested removing the O2 sensor and cat converter completely if I upgrade to headers... what are the risks and challenges involved? I assume there would be no chance in hell that the car would smog if I had to do so in the future.

[Geezer]

I don't have a problem with you removing the converter if smog is not an issue in your area. If smog is an issue leave it in place. What ever you do retain the O2 sensor. Without it the car will run like cr@p.