1979 Exhaust Manifold to Head Bolts. GM Numbers?

[Paul L.]

I need the GM numbers for the 1979 exhaust manifold to head mounting bolts. I believe there are eight end bolts and four centre bolts. I do not have A/C. Thanks!

[Joe L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Paul-----

The long bolts are GM #3733134. The short bolts are GM #3736035.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Thank you! I shall place the order today.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Those bolts are in stock in GM Canada depots. I will have them in several days. It does look from the parts book that one or more are studs rather than bolts. But it is unclear. Can anyone advise?

[Tom R.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Along the same lines (that being of the exhaust), what are the part numbers for the bolts & nuts that connects exhaust pipe to the catalytic converter?

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Tom,
I believe the bolt is 9418824 and the nut is 1249488 (eight of each required).

[Tom R.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Thanks Paul...and do you know whether they are available through the GM Canada Depot...and how?

[Joe L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Tom and Paul-----

The GM #9418824 bolt and GM #1249488 nut were PRODUCTION-only pieces and were never available in SERVICE. For SERVICE, bolt GM #3736035 (same as exhaust manifold short bolts) can be used. A similar-to-original flanged nut can be obtained under GM #9442958. The GM #3736035 is an SAE grade 8 fastner and the 9442958 is an SAE grade 5, as original.

To be honest, though, if it were me, there is ABSOLUTELY NO WAY that I would use a plain steel fastner for this application. I would use only stainless steel. A 3/8-16-1-1/4" stainless steel bolt is easily available in a hardware store. Also, a 3/16-16 stainless steel nut and washer (to replace the original flanged head nut) is also easily available. Hardware store "2-line" stainless bolts are more than adequate for this application. However, if you want to get fancy, you can obtain high-strength ARP stainless bolts and nuts.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Joe,
I agree with you. SS bolts and nuts can be had for less than $1.00 each. I have a small inventory in the basement. But I can check those numbers tomorrow for Canadian availability if Tom wishes. My experience tells me they will come in at about $5.00CDN each....Tom, let me know.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Any update on this? Are some studs rather than bolts? I am thinking of the heat stove on the driver's side.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Joe,
I received the #3736035 bolts from GM Canada. Those are the short bolts (8). For the long (4) I ordered #3733134 but they seem much too lengthy. Do you have a number for the long bolts? Or if one wishes to go SS what is the length?

[Joe L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Paul-----

The GM #3733134 bolts should be 2-27/32" long. Those should be the proper length for the small block exhaust manifold center bolt positions.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Joe,
They are indeed that length. So it appears that I have the right combination of short and long. I am still musing about your suggestion to go SS however.

[Joe L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Paul-----

When I was talking about stainless steel bolts earlier, it was in relation to the catalytic converter flange bolts. For those bolts, I would only use stainless. However, for the manifold attaching bolts, the use of stainless is not so critical. The standard factory bolts usually work quite well and there usually is not a problem with removal of them when the need arises.

[Paul L.]

Re: 1979 Exhaust Manifold to Head Bolts. GM Number

Thanks! Then I am all set for an exhaust manifold/AIR injector tube refurbishment.