bbk longtubes/collectors

[a_k]

I've decided i'm going for some bbk longtubes this time around, i have mac shorties right now and the quality isnt there. I was looking for some 1 3/4" headers but I can't find them for the 94-95???? All I can seem to find is the 1 5/8" ones. The larger diameter would be better for the 331 right? Also I searched the forums and i've been reading about the collectors being too small on the bbk's and everyone likes to mod them. If anyone had any pictures of this that would be awesome.
Thanks
Adam

 

[5spd GT]

The collectors on the BBK 1 5/8 in. headers are 2.3 inches wide. Opening them up to match the 2.5 in. pipe is very little...don't expect anything. I'm doing it anyways...just to say "I did"...

You will get more if you port out the inside of the primaries where they bolt to the head and smooth it out. Since the welds are thin from the inside, you will want to probably weld them from the outside or have someone that can do that...

 

[352Ford2]

why do you want to run 1 3/4" primarys? idealy you want to run the smallest tube size that doesn't produce turbulent flow. if you run any bigger than that you will hurt scavanging

 

[a_k]

oh alright thanks alot. I thought for a 331 1 3/4" was better. At least that's what someone told me. I'll have to order up some 1 5/8 longtubes and and o/r h then

 

[5spd GT]

I personally don't think 1 3/4" are needed unless you got a primarily track car...because you'll be spinning "high rpms" for the majority of it's needed driving. Not saying it is to big...but I do not believe it is needed. Some think bigger is better, I don't...

 

[86bluecobra]

i have bbk shorties and i don't know about the LT hardware but on mine the 2 studs they gave me with the headers to install to the h-pipe after only a month would not come loose. They were like low grade stainless l believe and stainless and heat isn't such a good mix i found out. i broke the studs off then i had to remove the header and remove the rest of the stud. i would recomend mild steel studs and not the stainless they provide. unless they changed what they give you.

 

[JBeezy53]

Yeah the 1 5/8"s would be a better choice. IMO.

 

[Grn92LX]

1 3/4" are needed depending what the rest of the combo is. I would go 1 3/4" and open up the collector to at least 2.5". Its very restrictive especially for a stroker. When I swap to a 3" mid pipe I have to open up my collector a little more.

Just because you run an 1 3/4" primary doesn't mean its a track only car or a high rpm car lol. Go with a custom cam and follow what your grinder tells you to do. The cam has a LOT to do with what size primary you need.

My cam grinder (Ed Curtis) was the first person to tell me about the BBK collector when I asked him about swapping to LT's on my 302. He told me its a smart move but to open up the collector because "its tiny down there".

 

[a_k]

hmm well i just ordered the ceramic coated 1 5/8" headers from summit so I hope they will work ok. ed is going to be doing my cam too, next paycheck i'm sending him money.

 

[5spd GT]

1 3/4" are needed depending what the rest of the combo is. I would go 1 3/4" and open up the collector to at least 2.5". Its very restrictive especially for a stroker. When I swap to a 3" mid pipe I have to open up my collector a little more.

Contradictory statement. They cancel each other out...

Opening it up to "atleast 2.5 inches" compromises exhaust seal...

I would hope you would open it up a bit...since it will match better. He is not going to have a 3 in. mid-pipe.

Just because you run an 1 3/4" primary doesn't mean its a track only car or a high rpm car lol. Go with a custom cam and follow what your grinder tells you to do. The cam has a LOT to do with what size primary you need.

Your having a bit of reading comprehension problems (no offense). I said "primarily track car": meaning that is majority of why you would want something like 1 3/4". I also did not say it is a "high rpm" car...you will be at higher rpms when you run down the track. You don't putt putt at the track do you?

My cam grinder (Ed Curtis) was the first person to tell me about the BBK collector when I asked him about swapping to LT's on my 302. He told me its a smart move but to open up the collector because "its tiny down there".

How about that, he is my cam grinder too.

There is a very small difference in 2.3" to 2.5"...if you are trying to do all the little tricks in the book...then do it. Other than that it is a very small difference. I have them right here in front of me, off the car...very small. 2 millimeters That will atleast give a mph or 2 if you open it up