350 exhaust manifold

Hello , I have a leak from botth manifolds and I wonder if they happens to be cracked or damaged when I took em off (wish it was only gaskets replacement but ... )

Is there any new exhaust manifold replacement on the market today that would be bolt on ? Not looking for headers

The engine is a 1968 350 2bbl automatic

Thank you

 

And what year will fit (interchange) to my 68 if ever I cannot find new parts ?

Donald

 

Anyone ever try this model ??
https://www.summitracing.com/int/pa...make/buick/model/skylark/engine-size/5-7l-350

 

Donald,

Just remove your manifolds, bring them to a machine shop & have the faces surfaced flat. Of course check them over for any cracks. NO gaskets are used as Buick wanted the heat dissipation. TOO much heat causes cracks. Gaskets would are an insulator & cut down on the heat dissipation. DON'T use hi-temp sealer either as it also effects heat dissipation.
Shouldn't be any more than $50.00 a manifold.

Tom T.

 

That summit racing manifold is for LS swap cars. try having the machine shop clean up
Surface.

 

Hello Tom , you mean they goes directly surface to surface , no gasket or anything were use there ?

If there is any cracks is it possible to have them easily weld ?

 

Yes. Surface to surface.
Welding is a "hit or miss" fix.
Better to get good used manifolds than spend time trying to have them repaired.

 

Welding or Brazing

 

Saw that on the Hemming website :

So if I need to replace mine I'll have to check for those years ?

Here's some pictures I found ... 13 bolts .... hope it goes well when they took em off the car !!

 

If I ever had to go with headers on my car , are they bolt-on ? ?

Or What should I expect ??

Thank you

http://www.taperformance.com/proddetail.asp?prod=TA_2010CH

 

Headers are a pain to get in and bolt it. And it’s best to rejet carb as it does lean the mixture

 

Did it ended well with after some adjustment ?

By any chance do you gain any power or improvement ?

 

Some gains in upper Rpm. They tend to leak, there are better gains in other places. Try to get gaskets or machine cleanup the manifold

 

Headers are not that hard to put on you put the rear end tires on ramps and jack the front end up good and high and install them. The center bolt is the hard part and you just have to use the wrench and keep flipping it over to tighten.

Yeah it's a little hard for that center bolt but not that bad, probably gain 10-15 hp.

I use stainless steel bolts and just keep tightening them up after a couple of warmups and they should not leak for a very long time. You buy 2 sets of gaskets from TA so you are ready in case you get a leak.

 

There is more chance that the next time they leak it will be gasket job more than resurfacing the headers ?


I don't know for sure if I will need them ... depend if the manifold are cracked or not ... do you needed to play with the carb after installing headers ?

Thank you

 

Probably need a little more gas but maybe not. You would have to go to the track or a dyno and make the changes to see if you gain in mph or more hp on a dyno

The headers will use a gasket so there will be no need to resurface headers.

 

Hello , I went to the garage this week to showed up the engine and from what he saw he think the manifold are good enough (no crack or else to be affraid of)

He then order some aluminium made gasket then he'll start the job prolly next week !

I keep fingers crossed

 

Update : The job was done last friday and the mecanic tell me that my exhaust manifold were still very solid ! No need to resurface them , older gasket were broken for long .... what a difference it makes !!! It's like a new car lol