Trying to find the largest shorty headers possible (long tubes are not an option as I have sportline springs). I'm building a fairly stout small block, and the engine builder recommended 1 7/8" super comp headers. There's just no way that these will clear without running duals. I see that edelbrock makes 1 3/4" shorties, but they are rather expensive. Is there a better (cheaper) option out there?

I'd like to spend as little as possible on headers and a 3" y pipe, as it is only a temporary "solution" to the problem and will eventually be replaced.

 

Don't go for the edelbrock headers...over priced imo. I also don't like the design either. If these are the ones you are talking about, then look at where the tubes collect at. They are all pinched closed.





I have a set of these on my IROC. They are the summit shorty headers. They flow so much better over the stock manifold, and they are cheap as hell @ $87. You cannnot beat that price. And look at the design compared to edelbrock...smooth sailing all the way through the collector. I know you said you want the biggest, but you also said you want the cheapest...well, these are the cheapest, and if oyu are taking them out soon anyhow to replace them...I would go with these.

_Clark

 

by the looks of it they're 1 5/8ths? They would work, but the amount of power I'm going to lose would be pretty substantial!

Thanks for pointing out that the edelbrock's were all pinched. I didn't realize that. I just find it hard to believe no one has a lowered f-body with a high output motor. Does everyone in this situation just take the power loss of using the 1 5/8ths?

 

Can't think of anyone who makes a half-assed header in mass production off the top of my head... SLP's 1-3/4" is a quality header that has dual 2.5" collectors feeding into a 3". Anything better will be long tubes into a mufflex y-pipe, or true duals and get the car out of the weeds(speedbumps).

 

id go SLPs if u want 1 3/4s but they to are fairly expensive

 

Well if long tubes are the way to go... is there any way to NOT scrape with a single piped catback? I live in Wisconsin for God's sake. Our roads suck up here.

 

 

I would only use 1 3/4" primary headers on a 383 or a 350 that I intended to rev past 6000 RPM often. 1 7/8" is pretty crazy if you ask me unless you have a 400.

 

Exhaust gas is hot and wants to expand. 1 3/4" is the outside diameter, so you can figure the inside is about 1 5/8". That's 1.625 in decimal. If you have a set of 1 5/8" headers (about 1 1/2" or 1.5" inside), think about this: Your exhaust valves are stock 1.5". If you have aftermarket heads, you probably have 1.6" exhaust valves. Now tell me why you would want 1.6" of hot exhaust valve feeding into a 1.5" port? Doesnt make sense to me. 1 3/4" headers are the way to go for any 350 and larger.

I only know of SLP that makes 1 3/4" shorty headers. Edelbrock DOES NOT! They only make 1 5/8".

 

SLPs do not have a 2.5" collector. The ID is just under 2.25". Why they would go through the hassle of fitting 1 3/4" pipes only to stuff them into a 2.25" collector is beyond me... The collectors can be modified fairly easily though.

 

First, 1.6" valves don't flow as good as 1.6" pipe.

Second, my choice of primary diameter is based off of the peak RPM that the diameter will achieve. The diameters of the primaries determines what RPM the headers want to flow at similarly to how intake runners behave. According to my research, 1 3/4" primaries attempt to push the peak horsepower of a 350 engine to above 6000 RPM.

Third, if you have aftermarket heads with 1.6" valves, chances are you want your peak RPM to be above 6000 RPM, so if this is the case then go for the 1 3/4" headers. I still wouldn't use a 1 7/8" primary unless I had a 400 or a high revving 383.

 

There isn't much point in worrying about what type of headers when your going to run them into stock stuff from the cat back, that will restrict your exhuast a lot more than a eighth inch difference in the headers. I just installed a dynomax duall exhuast kit out of jegs for $135 and bought two thrush mufflers for 17.99 a piece, I installed it myself it hooked up easily and was really cheap, I have headers they are shorties but I couldn't tell you what kind except they are a small diameter. My car has a built 305 putting out 385 hp and right after I installed the exhuast I took it out for a drive hammered it and tore the tread off of the sidwall of my rear right kelly charger tire. I live in an area with a lot of bumpy, hilly back roads and am fond of getting airborne, and I have yet to scrape bottom.

 

The catback's not stock... I've got a hooker 3" catback right now, was trying to reuse it to save money if possible. The peak RPM on the engine I'm building is approximately 7500. It's a 355 for now, with a brodix topend, but trying to plan the exhaust for bigger and better things to come (eagle stroker assembly) once I have a bit more money to spend.

All the feedback was helpful and appreciated (except for the eyeroll guy). Thanks!

 

I can only respond to this part. Quite a lot of aftermarket heads come with 2.02 intake and 1.60 exhaust valves. Its a common upgrade as those are the largest valves you can easily fit with a 4" bore engine. They flow better at all RPMs than the stock valves of 1.94 intake and 1.50. It has nothing to do with the intended RPM range of the engine.

 

Yeah it does. Do you think that intake and head runner diameter affects the engines RPM range but the valve diameter does not?