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Curious if anyone has actually used these headers on a 350 motor and have they seen any real performance benefits in terms of dyno pulls etc. I understand these headers replace your exhaust manifolds with no necessary modifications and bolt right on. I’ve seen a few of the 455 ones up for resale which makes you wonder if people are dissatisfied with them. To me it’s a cheater header and I’m sure there are some power compromises as a result. I’m about to detail another set of exhaust manifolds for my 70 W31 as mine were quite pitted.
They are cast iron manifolds. They are designed to clean up a dual exhaust installation where someone doesn't want to use headers. I don't know that they would increase power or not, but I really don't think that was their intended application.
Al's talking about the new "shorty" small-block headers that Thornton just came out with not the "350 jr" cast iron manifolds. They look pretty decent, much better than the ones they had for the big-blocks! I haven't seen any dyno #s on them but I'm thinking about getting a set for a '69 W31 clone that i'm helping a buddy with. They also just came out with a similar shorty header for the big-blocks. Looks much improved over their first ones.
Here's their early big-block headers,YUK!!!. They look really restrictive!!! Other than the weight savings I'd stick with a pair of W-Z manifolds! I can see why people are re-selling them! But they are working on a much better design for the big-blocks. I saw them on their "fakebook" page a couple of days ago,They were in the "prototype" stage.
I have these, but they are still in a box in the garage... My long tube headers interfere with my clutch linkage, so I am going to change them out. I know what the car feels like with the long tubes - I'm curious if I will lose any seat of the pants feel or not. I hope I can get them installed in the next few weekends....
Al's talking about the new "shorty" small-block headers that Thornton just came out with not the "350 jr" cast iron manifolds. They look pretty decent, much better than the ones they had for the big-blocks! I haven't seen any dyno #s on them but I'm thinking about getting a set for a '69 W31 clone that i'm helping a buddy with. They also just came out with a similar shorty header for the big-blocks. Looks much improved over their first ones.
Shows what I know as I was unaware of these. They look pretty nice.
Troy needs to dyno a car with stock manifolds, his manifolds, shorty headers and long tube headers. All the same engine but with 4 different exhaust set ups. This will be the only way to prove that his products are NOT smoke and mirrors.
Troy needs to dyno a car with stock manifolds, his manifolds, shorty headers and long tube headers. All the same engine but with 4 different exhaust set ups. This will be the only way to prove that his products are NOT smoke and mirrors.
Ya think?
I'll even take back-to-back drag strip tests (with proper weather corrections). The fact that this has not been done even after the products have been on the market for a while should tell you something.
Why do people always try to compare these products to long tube headers?
These products are not produced to compete with long tube headers.Everyone knows if your a racer trying to wring every last hp out of your engine,you need long tube headers.
These products are produced to offer the Olds community some options.
There are plenty of people out there who do not want stock manifolds or long tube headers. Evidenced by the fact when I put my log style headers up for sale,they sold in 3 days.
Last edited by w-30dreamin; September 14th, 2018 at 08:56 PM.
Why do people always try to compare these products to long tube headers?
Because the sellers and proponents of them try to equate them with real headers. They are a lot of money for very little benefit. If someone wants to use them, that's their choice. My only point is that people should make an informed decision before parting with their hard-earned cash. Those crappy BBO tubular manifolds likely flow worse than factory W/Z manifolds, which actually have internal runners. The fact that people buy this stuff is not "proof" that the parts are worth the money, it's only proof that there are uninformed buyers.
Well said W30deamin and Joe. You see quite a few of these for sale that people have bought but never used. I’m sticking with my factory exhaust manifolds for sure.
We all know Joe thinks shorty headers are near useless. Some of us disagree but until a dyno test is done, who knows. They also need 307 tubular manifolds included in that test😉. Stock SBO manifolds are restrictive, the Thornton design looks as best as can be done to fit in place of awful stock manifolds.
Stock SBO manifolds are restrictive, the Thornton design looks as best as can be done to fit in place of awful stock manifolds.
That is what drove my decision to buy them. The long tubes on my car are in the way of critical parts, and I wanted something better than stock that would let me adjust my linkage, not heat up my starter, and still look nice. If it comes down to them just looking nice, I'm OK with that
Why do people always try to compare these products to long tube headers?
These products are not produced to compete with long tube headers.Everyone knows if your a racer trying to wring every last hp out of your engine,you need long tube headers.
These products are produced to offer the Olds community some options.
There are plenty of people out there who do not want stock manifolds or long tube headers. Evidenced by the fact when I put my log style headers up for sale,they sold in 3 days.
Well said W30deamin and Joe. You see quite a few of these for sale that people have bought but never used. I’m sticking with my factory exhaust manifolds for sure.
The reason for selling them before trying them probably has something to do with guys bashing them using nothing but looks. I've never seen a product get so much negative responses based on how they look. I know a certain NHRA P/S racer who experimented with square tube headers.that's right,square tube headers. They didn't improve HP but didn't hurt HP either but if you saw them,didn't look like much.
The reason for selling them before trying them probably has something to do with guys bashing them using nothing but looks.
My comments are based not only on "looks" but on my background and experience with subsonic flow. You WILL get turbulence and flow disruptions at the square corners. That's physics. The factory W/Z manifolds do not have such intersections. The interior is divided into individual runners, with smooth, parallel transitions where the runners join. Again, the factory engineers were not stupid.
Frankly, simply using better, curved transitions where the individual cylinder pipes meet the main pipe would have made a world of difference.
Because the sellers and proponents of them try to equate them with real headers. They are a lot of money for very little benefit. If someone wants to use them, that's their choice. My only point is that people should make an informed decision before parting with their hard-earned cash. Those crappy BBO tubular manifolds likely flow worse than factory W/Z manifolds, which actually have internal runners. The fact that people buy this stuff is not "proof" that the parts are worth the money, it's only proof that there are uninformed buyers.
Just to clarify Joe,
Thornton the original producer and seller of the products in question is the one that told me in a phone conversation,these are not designed to compete with full length headers.
I said the same thing in my above statements.
Who is trying to equate them to "real" headers?
For my wants and application there are many benefits.
"Likely flow worse",without testing,this is a personal opinion.
When I used the word "evidenced",having my log style headers sell in 3 days is "proof" there is a market for these products.
Just to clarify Joe,
Thornton the original producer and seller of the products in question is the one that told me in a phone conversation,these are not designed to compete with full length headers.
I said the same thing in my above statements.
Who is trying to equate them to "real" headers?
For my wants and application there are many benefits.
"Likely flow worse",without testing,this is a personal opinion.
When I used the word "evidenced",having my log style headers sell in 3 days is "proof" there is a market for these products.
While I agree that "likely flow worse" is an opinion without test data to back it up, it is at least an opinion based on an aerospace engineering degree and four decades of experience designing, building, and flying things in the aerospace industry. While subsonic flow is not always intuitive, there ARE some rules of thumb that we've learned in the last century plus of flying things through the air. I never said that Thornton claimed that these were equivalent to real headers. My comment was about the many uninformed proponents of these items who call them "shorty headers". They are not even close. I still don't understand why Thornton would even waste the time on these given that they already sell repro W/Z manifolds.
As for the market for these, there are lots of items bought by people with waaay more money than brains. Just watch any Barrett Jackson auction. Heck, people buy fidget spinners (well, they did for a while).
I know those Thornton log BBO manifolds were not a great design. But the 350 and just coming out big block shorty headers will out flow stock run of the mill regular Olds log manifolds, how much power they are worth is the question. I have mentioned the SBD manifold to multiple headers test on a 300 hp engine, I have had a set of those truck/van manifolds they started dyno testing with, bloody awful. I can get similar bolt on shorty headers for my Dakota for about $200 cheaper than the Thornton shorty's. I haven't bought a set because because Dodge actually shrunk their manifolds and down pipes for increased torque and these are still better than the old truck/van manifolds. I missed a clearance on the same size but manderel bent stainless y pipe, kicking myself there. It shows velocity is important if maximum torque is your goal, otherwise JBA would have enlarged it somewhat. The factory Y pipe is a kinked mess from new. Also I need maximum engine heat in -40 weather, cast iron manifolds hold in the heat for a long time after running. Even if shorty headers do almost nothing as you claim, my Ceramic coated Sanderson shorty headers are cool to the touch in a couple of minutes. So if vapor lock is an issue, ceramic headers may help.
I know those Thornton log BBO manifolds were not a great design. But the 350 and just coming out big block shorty headers will out flow stock run of the mill regular Olds log manifolds, how much power they are worth is the question. I have mentioned the SBD manifold to multiple headers test on a 300 hp engine, I have had a set of those truck/van manifolds they started dyno testing with, bloody awful. I can get similar bolt on shorty headers for my Dakota for about $200 cheaper than the Thornton shorty's. I haven't bought a set because because Dodge actually shrunk their manifolds and down pipes for increased torque and these are still better than the old truck/van manifolds. I missed a clearance on the same size but manderel bent stainless y pipe, kicking myself there. It shows velocity is important if maximum torque is your goal, otherwise JBA would have enlarged it somewhat. The factory Y pipe is a kinked mess from new. Also I need maximum engine heat in -40 weather, cast iron manifolds hold in the heat for a long time after running. Even if shorty headers do almost nothing as you claim, my Ceramic coated Sanderson shorty headers are cool to the touch in a couple of minutes. So if vapor lock is an issue, ceramic headers may help.
First, my comments are restricted to the crappy log manifolds. While I'm not a fan of shorty headers, the stock SBO manifolds are even worse. No argument there. I really don't understand your comments about vapor lock and -40 weather. How is vapor lock even an issue if it's that cold? And if you ARE worried about vapor lock, thinwall headers will cause the engine compartment to heat up much faster. Of course, heating is all an issue of rate. Thick wall manifolds only delay the heat transfer, but at some point, the outside temp of the manifold will be the same as the outside temp of the header. The only issue is how fast that happens. This is the same problem I have with starter heat shields and insulation. No insulation is perfect, so at some point, the temp at the starter will be the same with and without the insulation. In fact, the insulation can make it worse, because it works both ways - once the starter gets hot, the insulation holds the heat in.
Related to what Joe wrote, i once read a guy who was driving index class. Long story shory, he was laughing his way to start line, when other guys tried to cool down their engine as much as possible between the rounds, when he simply kept the engine at normal operating temperature all the time.
just to throw in my 2 cents worth of BS. I was watching one of those car TV shows. They decided to do a dyno test on headers. There idea was to bash the tubes in with a hammer. Similar what happens on some installs. Well they put some dents in them no HP difference. Then they smashed the crap out them, no HP difference. They almost had the darn headers smashed close before the HP started dropping.The hosts of the show, they seemed very knowledgeable, were very surprised by the results. So all this chatter about a lost HP because of the shape has me wondering about what I saw on TV. Is there really that much different HP lost on header design or do we have something else going on. More BS marketing to sell product or real world results. I would like to know.
just to throw in my 2 cents worth of BS. I was watching one of those car TV shows. They decided to do a dyno test on headers. There idea was to bash the tubes in with a hammer. Similar what happens on some installs. Well they put some dents in them no HP difference. Then they smashed the crap out them, no HP difference. They almost had the darn headers smashed close before the HP started dropping.The hosts of the show, they seemed very knowledgeable, were very surprised by the results. So all this chatter about a lost HP because of the shape has me wondering about what I saw on TV. Is there really that much different HP lost on header design or do we have something else going on. More BS marketing to sell product or real world results. I would like to know.
Mike
Yeah, that video has made the rounds. One restriction in a pipe is a venturi. Airflow speeds up to force the same number of gas molecules through the smaller area in the same amount of time. This is exactly how carbs work. The problem is that you can't equate a smooth dent in a smooth pipe to a right angle corner with interacting flows. You can't even equate one dent in one pipe in one specific set of headers on one specific engine at one specific operating point to anything else.
Sorry I meant vapor lock for +40 temps, only saw that once here this summer, in the deep South a much more common occurrence. The ceramic coating does help keep the exterior cooler but maybe that holds the heat in the motor like manifolds. We agree, shorty headers are better than regular Olds manifolds. The Thornton headers can be installed in minutes on a car with factory style dual exhaust on the ground, try that with full length headers, not going to happen. Remove the oil filter adapter and moving the brake distribution valve is just the start, whether they actually fit, welding etc. Is it worth it for 10 to 15 hp over shorty headers?
The Thornton headers can be installed in minutes on a car with factory style dual exhaust on the ground,
The factory exhaust is far more of a restriction than the manifolds. More to the point, the benefits from headers are additive. Yeah, simply swapping to headers with no other changes might give you 15-20 HP, but subsequent mods will be additive. Making HP and torque is all about moving air in and out of the motor. Improving the inlet side won't help nearly as much if the exhaust side is still a restriction. Yes, obviously there are different vehicles with different requirements. I have stock manifolds on my 67 Delta because 1) I can't get headers to fit and 2) it's a cruiser not a drag car.
While I agree that "likely flow worse" is an opinion without test data to back it up, it is at least an opinion based on an aerospace engineering degree and four decades of experience designing, building, and flying things in the aerospace industry. While subsonic flow is not always intuitive, there ARE some rules of thumb that we've learned in the last century plus of flying things through the air. I never said that Thornton claimed that these were equivalent to real headers. My comment was about the many uninformed proponents of these items who call them "shorty headers". They are not even close. I still don't understand why Thornton would even waste the time on these given that they already sell repro W/Z manifolds.
As for the market for these, there are lots of items bought by people with waaay more money than brains. Just watch any Barrett Jackson auction. Heck, people buy fidget spinners (well, they did for a while).
People buy FORDs fer cryin out loud...
Joe,
Just want you to know although I don't always agree with your personal opinion,I do highly value and respect the factual information you have shared with the internet over the years.
I have learned a lot from you! Your one of the guys whose posts I always read and usually learn from.
thank you
Joe,
Just want you to know although I don't always agree with your personal opinion,I do highly value and respect the factual information you have shared with the internet over the years.
I have learned a lot from you! Your one of the guys whose posts I always read and usually learn from.
thank you
Thanks for the kind words. Mature adults can disagree and rationally discuss differences. That's how we all learn.
The factory exhaust is far more of a restriction than the manifolds. More to the point, the benefits from headers are additive. Yeah, simply swapping to headers with no other changes might give you 15-20 HP, but subsequent mods will be additive. Making HP and torque is all about moving air in and out of the motor. Improving the inlet side won't help nearly as much if the exhaust side is still a restriction. Yes, obviously there are different vehicles with different requirements. I have stock manifolds on my 67 Delta because 1) I can't get headers to fit and 2) it's a cruiser not a drag car.
Agree the factory pipes aren't great but there are 2.5" manderel bend downpies Rocket Racing and Ram Air Restorations sell that bolt on those shorty headers. I would mention the Pypes stainless 2.5" manderel bend down pipes but their stuff has fit awfully lately. I am not happy with my current exhaust so the Thornton shorties and 2.5" down pipes with either Dynomax or Summit Turbo mufflers into my must have been made of gold, ridiculously priced tail pipes.
When I saw these I thought they would be a good replacement for the cast iron W/X manifolds in my 67 CS convertible. When I first replaced the stock 330 with a C headed 455 the exhaust was built around that configuration. The exhaust starts with Pypes down pipes to a Borla X cross over. The mufflers are Hooker Aero-chambers to Flowmaster mandrel bend ‘over-axles’ to Classis Chambered Exhaust short Powerstick as resonators all in 2.5” With the rebuilt engine having Eddy heads that have the individual exhaust runners I would think these ‘headers’ would be beneficial. The cam is a CompCam XE-268H-10 it’ll be a good street engine. The Thornton’s should be a good compromise until the exhaust hits that 90• bend and the fitment so far has been pretty good with the column shift linkage and such.
Iron exhaust manifolds on iron C heads were the previous engine set-up. Not a crazy cam profile but good for that lumpy exhaust note. Fits from the top and can bolt to existing Pypes down pipe. Always hated doing the drivers side but these tucked into place rather nicely. In keeping with the spirit of the 67 442 Factory exhaust set-up. These took the drone of the chambered mufflers away. Those are stainless rolled slash cut tips.
The original question on this post was regarding the fairly new Thornton SS Shorty's. It seems that the answer is NO there is not any real world performance data.
I have searched several sites with the same question with result being same answer.
Would everyone agree that these Thorton Shortys are an improvement (small power gain) over: Thorton 350 Jr Manifolds ? stock manifolds ?
What kind of expectation of gain seems to be the leading question I see. I think these Shorty's have been out near a year, right? .....and still I have not seen any data
A gentlemen on TA country is currently installing these shorty's and has had many exhaust combos on a T/A (long, short, xpipe, etc.) so I am eager to read what his feedback is.
-------------------------------------
Perhaps I should start a new thread with my questions ???
Reading through this whole post, it is making me question if I should consider long tube headers.
IMO with exhaust, if one is going to spend big or small $$, then might as well meet the goal to be one and done.
Regardless of anything I do, I must replace Y-pipe back on my T/A due to father time. Background:
I am in beginning stages of building up a 403 to replace my stock 403 which I will put on a shelf.
Brief Summary:
1. compression #7 heads
2. cam (not sure which; for another thread)
3. dual exhaust - 2.5" (I don't think my upgrades will be cause to need CFM for 3") ?
4. gear - leaning 3.23
5. keep 750 Q-Jet - rebuild; may remove bump
6. intake - not sure yet, will keep scoop so limited in choices
Now that the application build is known, all things being equal:
If Thornton Shorty's used, what is a rough estimate over stock manifolds (since data doesn't seem to exist yet) ?
If Long tube headers are applied, what is the expected performance gain be over stock manifold?
Note: With the Thorton 350Jr manifolds and their new SS Shortys' being both $299, I am not sure why anyone would not use the Shorty's ? Shorty performance is expected to be better & IMO SS looks much better.
Stock manifolds .- 0$; cleanup
Thornton 350Jr Manifold.- $299 1-5/8 ports to 3" collector
Thorton Shorty Header...- $299 1-5/8 ports to 3" collector
Hedman Shorty's......... .- $289 1-7/8 ports to 3"
Long Tube Headers.... .- $194 1-3/4, 18-gauge steel FlowTech ..#11150flt not painted for high temp
Long Tube Headers.... .- $149 1-5/8, 16-gauge steel Jegs ........#326455 not painted for high temp
Long Tube Headers..... - $240 1-5/8, 18-gauge steel Patriot .....#737H8301 - metallic coated
OMG !! I can get Long tube headers cheaper than manifold logs & Shortys? So from this post, I glean that for max performance long tube headers excel over Shortys' no matter what?
What am I missing: If these long tubes fit the cars as claimed, are cheaper, & add more performance.... what other considerations would cause anyone to not use long tube headers when upgrading from stock?
Which Long Tube Header listed above would be best choice in your opinion? yes, I know they are entry budget level long tubes.
If one should get tuned headers and spend more $$, are the gains significant enough to warrant for a street cruiser ?
~ J
'79 T/A .403 stock for the moment
Last edited by Via3d; September 29th, 2018 at 10:10 AM.
The original question on this post was regarding the fairly new Thornton SS Shorty's. It seems that the answer is NO there is not any real world performance data.
I have searched several sites with the same question with result being same answer.
Would everyone agree that these Thorton Shortys are an improvement (small power gain) over: Thorton 350 Jr Manifolds ? stock manifolds ?
What kind of expectation of gain seems to be the leading question I see. I think these Shorty's have been out near a year, right? .....and still I have not seen any data
A gentlemen on TA country is currently installing these shorty's and has had many exhaust combos on a T/A (long, short, xpipe, etc.) so I am eager to read what his feedback is.
-------------------------------------
Perhaps I should start a new thread with my questions ???
Reading through this whole post, it is making me question if I should consider long tube headers.
IMO with exhaust, if one is going to spend big or small $$, then might as well meet the goal to be one and done.
Regardless of anything I do, I must replace Y-pipe back on my T/A due to father time. Background:
I am in beginning stages of building up a 403 to replace my stock 403 which I will put on a shelf.
Brief Summary:
1. compression #7 heads
2. cam (not sure which; for another thread)
3. dual exhaust - 2.5" (I don't think my upgrades will be cause to need CFM for 3") ?
4. gear - leaning 3.23
5. keep 750 Q-Jet - rebuild; may remove bump
6. intake - not sure yet, will keep scoop so limited in choices
Now that the application build is known, all things being equal:
If Thornton Shorty's used, what is a rough estimate over stock manifolds (since data doesn't seem to exist yet) ?
If Long tube headers are applied, what is the expected performance gain be over stock manifold?
Note: With the Thorton 350Jr manifolds and their new SS Shortys' being both $299, I am not sure why anyone would not use the Shorty's ? Shorty performance is expected to be better & IMO SS looks much better.
Stock manifolds .- 0$; cleanup
Thornton 350Jr Manifold.- $299 1-5/8 ports to 3" collector
Thorton Shorty Header...- $299 1-5/8 ports to 3" collector
Hedman Shorty's......... .- $289 1-7/8 ports to 3"
Long Tube Headers.... .- $194 1-3/4, 18-gauge steel FlowTech ..#11150flt not painted for high temp
Long Tube Headers.... .- $149 1-5/8, 16-gauge steel Jegs ........#326455 not painted for high temp
Long Tube Headers..... - $240 1-5/8, 18-gauge steel Patriot .....#737H8301 - metallic coated
OMG !! I can get Long tube headers cheaper than manifold logs & Shortys? So from this post, I glean that for max performance long tube headers excel over Shortys' no matter what?
What am I missing: If these long tubes fit the cars as claimed, are cheaper, & add more performance.... what other considerations would cause anyone to not use long tube headers when upgrading from stock?
Which Long Tube Header listed above would be best choice in your opinion? yes, I know they are entry budget level long tubes.
If one should get tuned headers and spend more $$, are the gains significant enough to warrant for a street cruiser ?
~ J
'79 T/A .403 stock for the moment
I don't know about the TA chassis but with the 70-72 A body and long tube headers,you usually have to relocate the brake proportioning valve,use a high torque mini starter and you lose ground clearance.
With the shorty's you don't have any of these issues. Ground clearance is a somewhat large concern for me.I love the idea of 1/2 flanges on the shorty's. Check the flange thickness on some of the long tube brands.
Some say if you want quality long tubes you need American Racing or Hooker Super Comp headers and I have seen some bad reviews of the Hookers lately. Have you priced these compared to the entry level stuff?
So...are the long tube headers really cheaper when you consider everything?
For my street car shorty's make sense to me since I'm not trying to wring every last HP out of my engine and I'm after a non stock look.
Do not buy Flowtech headers. They rust even through ceramic coating in no time and they have thin flanges that need double gaskets to seal. The Hedman shorty's are probably the best flowing shorty headers, the have a 3" longer collector than the unmentioned Sanderson shorty headers and 1 3/4" primary tubes vs the 1 5/8" on the Thornton and Sanderson Shorties. I wish Thornton would copy the collector from the just coming out BBO bolt on shorties. The only restriction on them is the 2.5" outlet, the SBO neck down just before the outlet. Maybe it makes little difference but wouldn't you want maximum flow to the outlet? You can run full size starters with shorty headers, not so with most full length headers. The Hedman or Hooker full length are your best bet for affordable full length headers.
Shorty Headers
Thanks for affrimation on the Hedman Shorty's vs Thorntons. 1.75 out pipe & 3" collector
Great info re: the longer length on the collector too.
For Transam/Olds - I do not understand why people or excited on the new Thorntons offering when the Hedman specs are superior ??? I have read they fit.
What kind of approx. rough power increase would these Shorty's create? (rough, I know there are a lot of variables)
Long Tube
Still leaning towards long tube. I am learning form threads this would give a noticeable higher performance gain, correct?
I would prefer to stay with long starter, so good point, I am sensitive to fit.,
I have not looked at the Hedman or Hooker Long tubes you mention. Any input on the Jegs or Patriot listed above?
In regards to the primary pipe size
All the research I have seen suggests smaller exhaust pipe helps build low rpm torque,larger pipe helps build high rpm horsepower.
Why wouldn't this apply to the header primary pipe size also?
On the street I want low rpm torque.
I would be interested in seeing some research comparing collector length sizes on the same style header.
I don't know about the TA chassis but with the 70-72 A body and long tube headers,you usually have to relocate the brake proportioning valve,use a high torque mini starter and you lose ground clearance.
I did not have that experience with Heddman headers on either my 70 Supreme 350 or the 71 convertible 350. I retained the factory starter, had plenty of clearance for the brake proportioning valve, and the only time I scraped the headers was going over a railroad crossing at speed with 7 people in the vehicle. Different headers would likely give different results.
Shorty Headers
Thanks for affrimation on the Hedman Shorty's vs Thorntons. 1.75 out pipe & 3" collector
Great info re: the longer length on the collector too.
For Transam/Olds - I do not understand why people or excited on the new Thorntons offering when the Hedman specs are superior ??? I have read they fit.
What kind of approx. rough power increase would these Shorty's create? (rough, I know there are a lot of variables)
Long Tube
Still leaning towards long tube. I am learning form threads this would give a noticeable higher performance gain, correct?
I would prefer to stay with long starter, so good point, I am sensitive to fit.,
I have not looked at the Hedman or Hooker Long tubes you mention. Any input on the Jegs or Patriot listed above?
There is a guy in the 11's with the Hedman shorties. I say maybe 20 hp but don't quote me. One issue with the longer collector length on the Hedman is less ground clearance vs the Sanderson or Thornton headers. You need a nice tight custom bent 2.5" pipe off the collector. With Sanderson headers on my 70, a ton of room. On my 88 Cutlass it would scrape occasionally, depends car to car. Never heard of the Patriot headers, they look like Hooker Comp copies. Some install reviews would be nice.
Last edited by olds 307 and 403; October 1st, 2018 at 10:06 PM.
I thought I would revisit this thread since I finally did install the shorties in place of my rusted, ill-fitting long tubes. I used Pypes 2-1/2" downpipes and mated them to the remainder of my exhaust system after cutting the pipes just past the collector. They fit super tight in the engine compartment, and the passenger side actually needs to come out to flatten a relief where it hits the oil filter housing. But the goal was achieved - I can adjust my shifter linkage, the starter won't cook, and I can replace my front bushings without having to drop my exhaust system. As for the butt dyno? It's a dog. You can really feel the difference between these and long tubes. They look nice, and maybe someday I'll go back to a better set of long tubes. For now, they're fine.
September 11th, 2018, 10:17 PM
