Ok here's the scoop..its not backed up by dyno figures but by SOTP differences and I like to think Im pretty impartial about these things.


I installed my shorties last night with the help of a friend..actually I held the tools and he did the work..thanks JD!

I wont go into the blood and guts of the install cuz it was pretty much Uneventful except for two things...

I was installing a set that were Mfg'ed for the 00 LS1's on a 02..part # 1808 vs 1808-1 they fit but we had some problems..my advise woould not to go this way unless you get a good deal. The design of the set I had were different from others Ive seen. Not to the detrement of teh headers they just made the install a bit harder.

1. After the install we discovered that the steering knuckle was rubbing on the tubes which forced us to grind down the corners of the knuckle...not a big problem..but what a bitch it is getting tha thing in and out.

2. The guy who sold me the headers neglected to tell me that he or someone had broken a bolt off in the drivers side emissions (I think its the AIR connection..double diamond shape thinhgie) then tried to fix it by drilling out the bolt and bungled the job by leaving the bottom of the bolt in the hole... so I could not connect both sides of te tube to the flange thanks motorbuilt nice move... We got it on...we did the job right!

Ok the bottom line...
Anyway...What I can feel is the car seems to rev smoother, quicker. The car does seem to pull better when rolling down the road..its not a blazing difference but you can tell the difference....well worth the cost of admission that I paid for a set of used headers.

All that being said..those changes seem to point to a better system..which is why I di it in the first place. Im not trying to maximize HP just squeeze out as muchas i can while not pissing off the mann.

So all you Cali guys or anyone else, who want to upgrade your system with a set of headers, but want to stay legal here in the sunshine state, here's my recommendation ..get a set of JBA's Or other shorties I believe it dose make a difference. Yeah I didn gain 40 HP..but I gained some overt teh stock set up

Get a used set the new price is like 600 bucks way too much i think for a set of shorties and the probable gains.

And to all you shorty haters

BTW the biggest difference Ive ever felt after I installed something to date has been my ported TB...THAT has been the best 75 performance bucks Ive ever spent to date on my car and is really complemented the header change

 

longtubes or bust

 

Be ready for the bandwagon of hate, they tend to forget that if it makes you happy that's all that matters.

Sadly you can't do much in cali and shorties are a slight gain, even more so on the 98-00 cars. Not to an effective bang for buck but still it's a CARB legal gain and those are far and few behind.

 

Yeah I just want to get as much off teh tabel a s I can HP wise but still stay legal...

Yeah I know I know...I can see teh wave forming now...

Next on the list is my ASP underdrive pully...any haters there?

 

That pulley is going to feel like you're hitting a 100 shot.

Seriously, you should have done a before/after dyno. The butt dyno is INCREDIBLY inaccurate. My car feels like it drops 2 tenths whenever I wash the bitch. It felt faster after the coolant bypass. It's probably in your head. I hope that you gained power, but I don't have much faith in it. But, if I was in your situation, and picked up a set for $75, I'd throw those bitches on too.

 

Yeah I wis I could have done a dyno at each step..just didnt havethe bucks
I totally agree if were talking about QUANTIFYING anything..but I do believe that you can tell when something is diffrent or better..you just cant tell HOW MUCH

I felt No diff with the TB bypass..I do enjoy driving my car after I was it..but you can tell if your car is reving faster or smoother..both of which DO translate into better performance..but how much...your butt is as good as mine with a ruler

That came out wrong....

 

I would say buying used shorties are definitely worth it. Most people jump to the LT's right quick and pawn their shorties off like they're worthless (including myself). I sold my used Hooker's for $75 as well. While I am much happier with LT's, I still think shorties are a good route for emissions friendly people.

 

well now what else comes out of it besides rulers?

 

I didnt pick up much HP on the dyno when I swapped my manifolds for Edelbrock shorties on my '98 Z28 but the car dropped from 13.4s to 13.0s in the 1/4. The first time I went back to the track I thought they gave me the wrong time slip .

 

Bo..How much did you pick up..4/10 seems significant...

Im guessing that going to the shorties helped the cars "Breathing"..that might explain my experience with the car just performing a bit better.their is a very slight diff in acceleration .but that could also be because the car sound throatier

 

Did you swap the cats and midpipe when you fitted the shorties?

BTW the gain you are stating is probably correct. You said the most noticable gain was the ported TB, well it's worth about 5-8rwhp. So if the shorties where less noticable its logical to assume they gained 3-5rwhp which is bang on the money for shorties.

I would however expect throttle response to be much better and very noticable. However throttle response and HP are two totally different things.

n/a shorties will never make that much difference simply because the flow of the stock manifolds (espcially 01+) is actually pretty good and secondly and most importantly shorties don't scavenge over most of the Ls1's rev range.

They will however be great on a FI setup if you ever plan on a Procharger.

 

This is what I got swapping to Edelbrock shorties and a generic ORY made for shorties/factory manifolds:

 

Bo..thats a gain of ten.. or Am I reading that wrong....not bad...

Im guessing any real significant increase I got , if any is masked by the TB porting doen by Mr. White...

No I kept all the stock stuff ..but a set of Hi-flow cats was not in my original build off list but I'm thinking that I might be able to find a used set and pop those in and squeeze som more out of the system.

If I do Ill do the cats before I do my TD system and tune

As far as throttle response goes I agree I can equivocate any HP gain to response only the nebulous term "better performance" which may or may not have a HP component to it...it just might be that the system is more efficient.

Not mentioned in my original post is that I also replaced all the plugs and wires (original ones had 50 k on them) that might also be the reason I'm sensing something.

 

Yes, 10 or so but its across the whole powerband which contributes to a solid gain in acceleration from the line to shift rpm and so on in every gear. 10rwhp doesnt give you roughly a 40tenth drop in ET but 10+rwhp from bottom to top will.....my car did anyway.

 

Hey Bit Viper, I thought you were going all carb legal? If so, they high flow cats are probably going to be out of the question. I'm following your build up closely as I'm also trying to get the most out of my car being legal in Cali.

Nice info by the way.

 

yall need to find a shady shop that will pass you for 40 bucks

 

but wht if I dont....and even that is to much of a hassle for me..Im too CA to be botherd with looking for someone to pass my car....surfs up!

Oh I am....but Im wiling to cheat a little

Yeah I was asking the same question over in another thread. Outside of replacing the stock cats which I know is a no, no, cuz I heard thet you can only replace them if they fail, and I believe you need to authinitcate the replacement of them.... why cant I use Hi-flow cats will they not pass the emmisions portion of the test? An ..Im making a big assumption here that most places will turn a blind eye IF youve got CATs AND your not throwing any codes..big assumpton.

Replacing the CATS is not part of my orginal bulild so If I dont replace them no big deal..but in talking to a few people this weekend I thought Id look into it

 

I've heard the same thing as far as replacing the cats. You have to get some that are approved or something like that.

 

i would suspect that most of that HP increase is due to the ORY that he said he had.. those stock cats and Y are a huge restriction.

 

Question is..dose anyone ever check..or do they only check to confirm that they're are cats in the stock location..i guess the folds back on the whole CARB legal thing..why bother if its a toss up..thing is replacing the cats is really easy....i might not mind doing that every two years...and after saying that..why run cats at all....their are only 5 bolts that are VERY easy to get to to do that....it would be like converting the stock system into a defacto ORY

Hmmmm