scooter123

This might be a stupid question but Im no expert when it comes to performance .....Im pretty novice to be honest.

So Ive decided to purchase a set of headers and im on a tight budget!!
The headers are 3'' and my car has all new exhaust from front to back and its 2 1/4 and new flowmasters .....is it pointless to by headers and reduce it down to 2 1/4????

scooter123

Anyone have any info to help me out with this???

redoldsman

You need to tell us a little bit about you engine. Unless you are running a lot of engine, no way you need 3" headers. Bigger is not necessarily better. There are experts on here who are a lot better versed on headers than I am but they will not be able to give any good advice without knowledge of your engine. By the way, it may take a little longer than an hour and eleven minutes for somebody to reply.

pogo69

In my opinion it is definetly worth it maybe some fitment issues but it will sound better and exhale better, you shouldn't be dissapointed...you upgraded the cam so its a natural

oldcutlass

Most header collectors adapt all the way to 2", I don't see an issue unless your engine is heavily modified.

scooter123

Ok the headers are flowtech part# 11154FLT going on my 71- 455....mild cam/performer intake and i think where the exhaust pipe joins on is 3"....so I can just reduce there to 2 /14 into my exhaust pipe???

Thanks for the help guys ...like I said Im pretty novice when it comes to some of this stuff!!

oldcutlass

I assumed you had a 350, I like 2 1/2 with a 455, however I still think the 2 1/4 will probably work for you since thats what you've been running all along.

joe_padavano

Let's back up. When you say 3" headers, I assume you mean the collector diameter. This is normal. Headers are designed to be run open at the track, hence the 3" collectors. Every header comes with reducers to neck down to a smaller exhaust system size for street use. Personally, I'd use 2.5" instead of 2.25" for the exhaust system, but it will work. You will suffer a little increased backpressure from the smaller pipes.

brown7373

The whole rerason for headers is too speed the flow of exhaust from the engine. Generally speaking, the larger the engine the larger the tubes. On a smaller engine, or mostly stock engine, smaller tubes will build more exhaust velocity, to get the gasses away and allow the engine to breather better and suck in more fuel. Too large a tube and the exhaust will just sit there. So what size are the tubes, not the collector?

I think someone already said that bigger isn't better, necessarily.

67BB

Right. The 3" is more than likely the collector. Not always but in general the sb headers are 1 5/8 and bb are 1 3/4 for the down tubes.

scooter123

thanks for the input guys...... ya the collector is 3 inch.... im good to go!!

matt69olds

Most exhaust companies offer header collector flanges that go from 3 inch to 2 1/2 (or 2 1/4) that are about 10 inches long. Much better flow than the huge drop in diameter the shorter flanges offer.

oldcutlass

In your case it's not going to make much difference on the lenth of your collectors, it's more of an issue in fit.

scooter123

thanks guys!!