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Comparison Of ZZP Plog and Speed Daddy Headers

wa04compg

New member
Hey guys I have both a Plog and SD headers so I decided to grab some calipers and do a quick comparison for people since this question comes up constantly on which is the best route to take.
Primaries and Crossover Measured by OD
SD Front Header= 1.650
SD Crossover= 2.250
SD Rear Header= Still on car haven't measured it yet
SD Downpipe is 3inch

ZZP Plog= 1.650
OEM Crossover= 2.012
OEM Rear Manifold= 1.506
The outlet on the rear manifold measures 2.575 ID



Hope this helps people when deciding what route to take
 
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Thats all good information glad someone decided to take messurements.. but the main thing would be flow numbers.. how much flow do each of them have comapred to each other.
 
I agree...various people have talked about seeing different results on the dyno but have never provided any charts...I at least wanted to show specs of them next to each other instead of just taking everyone's word for it
 
Well goes to show you that a plog and 3in dp isn't too bad of a route. Its 2/3 of the way to headers. Ive ran with both setups,currently on headers and not much of a performance difference.
 
Yeah I am sure that on a dyno you see a difference but to a average person just doing bolt on parts that never plans to put there car on the dyno prob wouldn't notice the difference driving around...if this info had been available to me when I bought headers I prob would not have since I already had a DP that was 6 months old
 


The only thing that isn't as appealing about the plog dp combo is the price difference. Most the time you can get SD headers new for around $217 shipped. A brand new plog and a 3" catless downpipe is $313.37 shipped from ZZP. Sure you can buy a used plog and dp but you can also get a used set of headers for even cheaper a lot of times.
 
I personally don't like speed daddy headers. I had a set that I never installed on the car just resold them. Couldn't get them to bolt together even on engine stand.

Bad about speed daddy
1) flex is going to need replace eventually
2) ports don't line up to the heads
3) fit issues with the cross over.

Good about speed daddy
1) cheap
2) stainless
3) less restrictive than stock
 
1. mine are on the stock flex 3 years later so are quite a few members on here.
2. Mine line up just fine
3. I had no issues with fitment.


Sent from A Galaxy Far Far Away........
 
If your doing an installing on the car, I don't believe you will see if the ports are lined up or not. I could definitely see it on the engines stand that they weren't lined up.

Just food for thought, they are less restrictive than stock. I just don't think they are very good.

As far as everything else, I will just call it Chinese quality.

1)You don't no if the flex is going to last or not.
2)You don't no if there going to fit or not till you install.
3)Also throw away any gasket they give you.
 


The only thing that isn't as appealing about the plog dp combo is the price difference. Most the time you can get SD headers new for around $217 shipped. A brand new plog and a 3" catless downpipe is $313.37 shipped from ZZP. Sure you can buy a used plog and dp but you can also get a used set of headers for even cheaper a lot of times.

If you already have a Plog or DP or both moving to a set of SD headers may or may not be worth the time and money spent...there is always extra cost on top of the headers to they end up being more then just $217...this thread was to show people that if they already have the latter moving to a set of ebay headers may or may not net them huge gains like everyone says depending on there build
 
If your doing an installing on the car, I don't believe you will see if the ports are lined up or not. I could definitely see it on the engines stand that they weren't lined up.

Just food for thought, they are less restrictive than stock. I just don't think they are very good.

As far as everything else, I will just call it Chinese quality.

1)You don't no if the flex is going to last or not.
2)You don't no if there going to fit or not till you install.
3)Also throw away any gasket they give you.

I agree 100% my flex is good so far but who really knows how long it will last...my crossover never fit right and still doesn't...front o2 sensor hits the firewall from time to time and I am not going to beat the crap out of my perfect firewall that is extremely stupid...if you look closely at my pictures you will see that the ports do infact not all line up....if we want to compare quality chinese made ebay headers are going to loose imo....do they work for a cheap headers...absolutely just may not be worth your while if you already have a different setup
 
If you already have a Plog or DP or both moving to a set of SD headers may or may not be worth the time and money spent...there is always extra cost on top of the headers to they end up being more then just $217...this thread was to show people that if they already have the latter moving to a set of ebay headers may or may not net them huge gains like everyone says depending on there build
Oh yeah that makes sense then, yeah really no reason to go to headers since the restrictions in the exhaust have already been eliminated. From what I remember the rear manifold isn't restrictive at all.
 
If someone has a plog+dp and really want to move to headers I would say get a good name brand set that has no issues...and yes the rear manifold is a log type manifold not cast so the any restiction I would think would be minimal...there has been at least 3 threads lately about selling a plog dp to move into some sd headers so I started this thread to show people the actual differences
 
The only thing that isn't as appealing about the plog dp combo is the price difference. Most the time you can get SD headers new for around $217 shipped. A brand new plog and a 3" catless downpipe is $313.37 shipped from ZZP. Sure you can buy a used plog and dp but you can also get a used set of headers for even cheaper a lot of times.

This..

As far as gains are concerned I'm sure the plog/downpipe combo flow pretty good compare to headers.. Most probably won't notice the difference on the butt dyno. Price wise well if your buying both new headers are the better choice. Like everything it just depends on how must you want to spend and sometimes leaving good enough as good enough.
 


This..

As far as gains are concerned I'm sure the plog/downpipe combo flow pretty good compare to headers.. Most probably won't notice the difference on the butt dyno. Price wise well if your buying both new headers are the better choice. Like everything it just depends on how must you want to spend and sometimes leaving good enough as good enough.

I agree Red but this comparison is more for people that:

#1 already have Plog+DP or just DP
#2 don't really want to install headers
#3 looking for oem quality and fitment for less money then big $ headers

So for people that already have headers this thread does nothing for them
 
That's one reason why I recommend either or. Let's be honest the install on a plog and downpipe is a easier install and once you take into consideration the modification that most like to the to SDs.. Then the plog/dp combo seems like the better option. I'm glad you posted this information though.. Gives guys some awareness and makes the decision easier.
 
That's one reason why I recommend either or. Let's be honest the install on a plog and downpipe is a easier install and once you take into consideration the modification that most like to the to SDs.. Then the plog/dp combo seems like the better option.

Yeah it def comes down to personal pref and what the individual is willing to deal with...there has been comments made about how Plog+DP doesn't even compare to SD headers so this is good info for people in the future
 
Kind of somewhat off topic but wasn't ZZP having issues with their plogs.. Either cracking or not sitting flat? IIRC they were notorious for that.
 
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