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EarlHickey
05-02-2012, 08:10 PM
Has anyone built one?

Are there any pix available?

Thanks

Squall67584
05-02-2012, 08:14 PM
Proper as in individual pipes per cylinder, or as in equal length? Nearly all of the vendor headers are what could be called 3 into 1,but I've never seen anything described as equal length for a DeLorean.

EarlHickey
05-02-2012, 10:01 PM
I'd be interested in links to any that are available.

I've only found one and it won't do what I want.

opethmike
05-02-2012, 10:04 PM
pdeklvrptdba01.corp.siriusxm.com

TTait
05-02-2012, 10:48 PM
Welmoed can jump in here, but there is an owner in Holland who built his own, and uses it in conjunction with his own custom turbo...

EarlHickey
05-02-2012, 11:30 PM
Welmoed can jump in here, but there is an owner in Holland who built his own, and uses it in conjunction with his own custom turbo...

Thanks, I'd love to see the owner built turbo setup and have built a few as well.

However, turbo plumbing on the hot side can acceptably fall pretty far from the normally aspirated tree of optimized scavenging, much like the stock log manifold, and often has to do so in order to optimize turbo proximity to the exhaust ports.

Perhaps he'll have intake and exhaust port dimensions and maybe even volumes, I'd like to know those as well.

I'm doing two threes down drafting and trying to decide if I'm going to screw them to the heads or use the tuned runners. I like the runners and would like to have an reasonable idea of the max flow/hp they can accommodate in stock form. I suspect I like the straight shot down better and am not afraid to make them long enough to pick up the same pulses the runners do. I'm guessing the stockers, sans the CIS logs, do the 3rd and 4th pulses. If the stock runners aren't too horribly restrictive, I prefer to keep the carbs tucked under the engine cover.

EarlHickey
05-02-2012, 11:31 PM
pdeklvrptdba01.corp.siriusxm.com

Thanks, that was very helpful.

opethmike
05-02-2012, 11:39 PM
WHOOOPS! Meant to type deloreanindustries.com!

EarlHickey
05-02-2012, 11:57 PM
WHOOOPS! Meant to type deloreanindustries.com!

Thank you, I don't recall ever seeing such a collector design and is there some double wall action going on there that I am unaware of?



I'm not doing cats and don't want them at all. I don't even mind if the sound pressure levels start approaching borderline anti-social or hooligan.

Any others?

Nicholas R
05-03-2012, 12:05 AM
http://www.stainless-exhaust.com/
http://www.stainless-exhaust.com/wp-content/gallery/exhausts/delorean-with-cats.jpg

This is the system I used to have on my car. Actually thinking about selling it.

EarlHickey
05-03-2012, 12:19 AM
https://www.deloreanindustries.com/shop/media/catalog/product/cache/1/image/1646665260fae7927c44b27a0adb1ae5/s/p/spec-i-exhaust.jpg

http://www.specialtauto.com/delorean-parts/images/delorean-headers-polished.jpg

How does your system perform?

Are the primaries 1.5" OD and perhaps 0.065" wall?

Delorean Industries
05-03-2012, 09:36 AM
https://www.deloreanindustries.com/shop/media/catalog/product/cache/1/image/1646665260fae7927c44b27a0adb1ae5/s/p/spec-i-exhaust.jpg

http://www.specialtauto.com/delorean-parts/images/delorean-headers-polished.jpg

How does your system perform?

Are the primaries 1.5" OD and perhaps 0.065" wall?

That is correct. The top system is ours. The performance is great. A lot of owners on here have the system. I can't build the systems fast enough either. Next batch here tomorrow.

EarlHickey
05-03-2012, 10:18 AM
That is correct. The top system is ours. The performance is great. A lot of owners on here have the system. I can't build the systems fast enough either. Next batch here tomorrow.


Can you explain the collector to me then? Two things, the angle of convergence and the stepped collector, is the collector double walled and fully tapered inside? I'm not concerned with any concessions to primary lengths to facilitate cats, mine will not be subjected to emissions testing or inspection. Given that, would you still build the header as short to optimize a reasonably stock engine with a short duration camshaft?

What diameter primaries are you running?

Your fabrication and welding results are very nice. Do you back purge with argon or use SolarFlux?

btw.... I looked on your site at the camshafts, I didn't see specs on the performance cams and I'm far too salty to bite without them. I'm the kinda guy that would have one ground or edm my own lobes before parting with beerslips for less than full disclosure.

I look forward to getting to know you and perhaps even working with you. You are in Ohio, correct? What part or nearest to which major city?

Delorean Industries
05-03-2012, 12:36 PM
Can you explain the collector to me then? Two things, the angle of convergence and the stepped collector, is the collector double walled and fully tapered inside? I'm not concerned with any concessions to primary lengths to facilitate cats, mine will not be subjected to emissions testing or inspection. Given that, would you still build the header as short to optimize a reasonably stock engine with a short duration camshaft?

What diameter primaries are you running?

Your fabrication and welding results are very nice. Do you back purge with argon or use SolarFlux?

btw.... I looked on your site at the camshafts, I didn't see specs on the performance cams and I'm far too salty to bite without them. I'm the kinda guy that would have one ground or edm my own lobes before parting with beerslips for less than full disclosure.

I look forward to getting to know you and perhaps even working with you. You are in Ohio, correct? What part or nearest to which major city?

Just send me an email to deloreanperformanceindustries@gmail.com and I will send the cam card.
We are in Tallmadge Ohio which is in the NE corner of the state near to akron and cleveland.

All of our systems are designed and fabricated by Stainless Works. Everything is tig welded and fabricated in 304 stainless. No idea on how to measure the collector convergence honestly...... Will a picture do?

DMCMW Dave
05-03-2012, 01:07 PM
FYI - here is a shot of the DMC Houston header (one of them anyway). You'll notice it has much longer tubes (equal length) than the others, depending on what you are going for that may do better. Available only as a whole system, including muffler, 2 cats, 2 outlets, and all mounting hardware. This shows uncoated T304 SS and the ceramic coated option.

Non-Cat off-road pipes available separately.


Also a shot of an installed system.

10061

10062

Delorean Industries
05-03-2012, 01:27 PM
One of the best features of our system is that it actually "fits" the fascia and is tucked up like a system should be. The muffler is designed not only for performance but noise control as well. No mig welded joints. No slip joints. Thick flanges to reduce warping. Oxygen sensor bung that will not distort and prevent the 02 from being removed. Integrated heat shield and the list goes on and on.

EarlHickey
05-03-2012, 03:53 PM
Just send me an email to deloreanperformanceindustries@gmail.com and I will send the cam card.
We are in Tallmadge Ohio which is in the NE corner of the state near to akron and cleveland.

All of our systems are designed and fabricated by Stainless Works. Everything is tig welded and fabricated in 304 stainless. No idea on how to measure the collector convergence honestly...... Will a picture do?


Thanks and I do get up that way and about an hour west of you.

I got a better look at the angle, from another picture, and it appears within the realm of usefulness.

EarlHickey
05-03-2012, 03:59 PM
FYI - here is a shot of the DMC Houston header (one of them anyway). You'll notice it has much longer tubes (equal length) than the others, depending on what you are going for that may do better. Available only as a whole system, including muffler, 2 cats, 2 outlets, and all mounting hardware. This shows uncoated T304 SS and the ceramic coated option.

Non-Cat off-road pipes available separately.


Also a shot of an installed system.

10061

10062

Do you know the primary ID and approximate length? What size ID is at the end of the collector?

My guess is the ID would be the OD minus about 0.125"

Nicholas R
05-03-2012, 05:21 PM
Do you know the primary ID and approximate length? What size ID is at the end of the collector?

My guess is the ID would be the OD minus about 0.125"

At the risk of sounding ignorant, I'm curious as to why you need such detailed specs on each. Dont get me wrong, I totally understand doing your research, personally, I just dont understand well enough how all these differences and specs affect performance. I know a lot of times, header tube length is simply determined by what will fit.

Again, not trying to jab or insult you for asking so many questions, mearly curious. :D

EarlHickey
05-03-2012, 06:59 PM
At the risk of sounding ignorant, I'm curious as to why you need such detailed specs on each. Dont get me wrong, I totally understand doing your research, personally, I just dont understand well enough how all these differences and specs affect performance. I know a lot of times, header tube length is simply determined by what will fit.

Again, not trying to jab or insult you for asking so many questions, mearly curious. :D


A tuned exhaust, for specific characteristics, is of very fixed dimensions and those numbers, not available space constraints, determine how much of a tangled mess of snakes the actual pipe is, what happens between the collector and muffler is secondary to the function of the scavenging effect of a well designed header. After that point matters virtually zilch unless it's completely corked.

A high rpm and high horsepower header will have certain defining features and one that produces torque and great mid range will have others.

You can do the basic math for exhaust systems and it's been proven that when the math absolutely works, you got lucky as it does not take into account a phenomena known as "unsteady viscous flow" and a couple other variables. Regardless, there are still more than soft relationships between primary diameter, length and valve events with collector design and variables playing a huge role in how and where a header works best.

Of course when there is zero, or less than zero space for an effective design, you gotta do what you gotta do and just about anything would be better than the stock cast iron log. However, I don't see physical constraints being a problem on these cars, especially if one doesn't want any cats.

Check out Burns Stainless or? Exhaust for some basic info on design. They do make some of the finest exhaust systems I've ever seen, and it's very likely you've seen many of them too, if you observe any world class high end racing events. I'm sure there are plenty of sites out there going into great detail and I could suggest a few good book titles if you want to delve deeper into tuning specifics.

I generally do my own induction and exhaust designs as well as their fabrication. I'm not opposed to buying what I want, already made, if it exists.

Do you know if a header for an even fire PRV would be optimum for an odd fire PRV? And vice versa?

Have you ever seen a header for a flat cranked V-8? Look one up and then we can talk about fitting pipes where space allows. ;-)

I don't suppose I've ever just bought parts such as heads, cams, headers, etc without knowing their full specifications and blueprints. I've even been known to send camshafts back that didn't match the card for various reasons including polydyne errors...and I mean to the big guys..... most people don't know how to check and maybe wouldn't even if they did.

EarlHickey
05-03-2012, 11:55 PM
At the risk of sounding ignorant, I'm curious as to why you need such detailed specs on each. Dont get me wrong, I totally understand doing your research, personally, I just dont understand well enough how all these differences and specs affect performance. I know a lot of times, header tube length is simply determined by what will fit.

Again, not trying to jab or insult you for asking so many questions, mearly curious. :D

http://www.burnsstainless.com/theory.aspx

Here, this will get you started. Look through their online catalog, which isn't nearly as impressive as their printed catalog or holding the pieces in your hands, but, it will show you other ways of doing things.

I have a couple of three into one collectors that I hydro-formed, sitting on my desk. They scavenge very well, but, I'm not sure they do as well as the burns collector. Now when I build them, I do them like you'll see in the catalog with a bit more scrap and wasted time resulting from things not going well, compared to other methods.

They also do 321 and Ti... very pricey, but, if you're running nitro methane and lots of boost... it's nice for your pipes not to melt.

I'm pretty sure the PRV would be a cool engine to supercharge.

My car has the automatic so I don't think I'll even remotely be considering making 3 ft/lbs of torque per CID, or crazy HP numbers.

justlooking
05-04-2012, 12:53 AM
At the risk of sounding ignorant, I'm curious as to why you need such detailed specs on each. Dont get me wrong, I totally understand doing your research, personally, I just dont understand well enough how all these differences and specs affect performance. I know a lot of times, header tube length is simply determined by what will fit.

Again, not trying to jab or insult you for asking so many questions, mearly curious. :D

Speaking of curious, Nicholas, you have a PM. :D

Farrar
05-04-2012, 12:19 PM
I'm pretty sure the PRV would be a cool engine to supercharge.

It's been done. I found this using Google: http://autoholics.com/2012/01/31/-First--Factory--Supercharged-DeLorean-604052

DMCMW Dave
05-04-2012, 09:34 PM
Here's the Houston Demo/Development car. If you are in the Chicago area tomorrow come by and drive it.

10098

sean
05-04-2012, 09:38 PM
Here's the Houston Demo/Development car. If you are in the Chicago area tomorrow come by and drive it.
10098

Very nice, is that an OEM header bottle? Looks to concours to be in that engine bay :D

DMCMW Dave
05-04-2012, 09:51 PM
Very nice, is that an OEM header bottle? Looks to concours to be in that engine bay :D

This is one of the Reproduction plastic header bottles that will be out shortly. Sorry, don't know the price yet. I probably just leaked something I shouldn't have, but it's a test car. . . .

sean
05-04-2012, 09:55 PM
. Sorry, don't know the price yet. I probably just leaked something I shouldn't have, but it's a test car. . . .

:D I thought you may have...

DMC5180
05-04-2012, 10:39 PM
This is one of the Reproduction plastic header bottles that will be out shortly. Sorry, don't know the price yet. I probably just leaked something I shouldn't have, but it's a test car. . . .

I would be more than happy to test one :tongue2: Glad too see it is continuing to be pursued for production release.

EarlHickey
05-04-2012, 11:07 PM
Very nice, is that an OEM header bottle? Looks to concours to be in that engine bay :D

Nice, is the blower three lobe? Straight or screw?

It does not appear to be driven by a synchronous belt, correct?

How much boost are you running and did you lower the CR?

Beautiful work, kudos.

Delorean Industries
05-06-2012, 10:13 AM
Nice, is the blower three lobe? Straight or screw?

It does not appear to be driven by a synchronous belt, correct?

How much boost are you running and did you lower the CR?

Beautiful work, kudos.

This right here:
http://www.boostecus.com/
You can actually buy the majority of the generic stage III components one by one directly through this company. Including the supercharger, outlet housing, inlet housing with auxilary injector spacer, bypass flange etc. Everything is listed for sale on their site under cast components I believe. Minus the front cross over to intake pipe and the throttle plate to supercharger section you can build our own stage III for less then 3k.


additional note that I missed- the cross over pictured on the front page of their site is comprised of three different components welded together all available on the cast products page as well.

EarlHickey
05-06-2012, 11:06 AM
http://www.hotrod.com/techarticles/engine/113_0208_chevy_43l_262ci_v6_engine_build/viewall.html

http://image.hotrod.com/f/techarticles/engine/9068904+w794/113_0208_v6_13_z.jpg


Look at the dyno chart for this pushrod engine..... I've not looked at any, yet, for the DMC tubular exhausts I've seen so far, but.... what I know just by looking is that none of them (seemingly designed for 10-13,000 rpm) come close to this one's fat and flat torque band as well as amazingly flat HP curve. I can also tell you what is shown in this article and not mentioned is this engine's amazing BSFC numbers, but, what it being pimped here isn't quite the same as what actually ends up in the winner's circles, the more sophisticated cheater stuff that very few ever get to see up close or lay hands upon..... ;-)


Notice this engine is all done at 6000 rpm and it would be very easy to change a few exhaust parameters to rock the curves upwards or downwards. If you've never driven a ride with a BGN V6, you should. The PRV has much more potential (the exhaust ports appear to be miserable) and the best I can tell, the CIS system, with some easy mods, can accommodate 275+ horsepower, normally aspirated, with wider HP and torque curves of the BGN engine, due to it picking up the 2nd, 3rd and 4th pulses and a couple other superior design features.

Does anyone have any interest in designing and fabbing a much more scientifically based header unit, with or without cats? I promise I'm going to build one for my car and wouldn't mind at all sharing with somebody more in a position to replicate and produce multiple units for road or track use.



Now, back to the blower, if you know would you answer what I've asked and also what displacement is the unit used for this application?

I clicked the link and got the naked orange page, didn't see anything specific to the car shown with one, waded through a few pages and couldn't find simple specs or determine if is machined from a casting or billet, much less any other specifics since I'm too lazy to download a PDF of FAQ's even!

Myself, I'd be inclined to sync a three lobed screw with lined tips, most likely a very inexpensive and readily available Eaton unit. Maybe even cleverly as to get some free counter balancing.

I'm not a fan of billet blowers, due to their less than favorable coefficients of expansion. If the lobes are straight... less of a fan for this engine for obvious reasons, if the lobes are billet and especially billet and not tipped with teflon... again even less.


Regardless, the blown car and it's execution is visually very nice. Does it have any dyno sheets or useful track time slips?

opethmike
05-06-2012, 11:18 AM
Dyno info here:

http://dmctalk.org/showthread.php?2530-Stage-I-II-and-III-details-and-pricing

Delorean Industries
05-06-2012, 11:22 AM
http://www.hotrod.com/techarticles/engine/113_0208_chevy_43l_262ci_v6_engine_build/viewall.html

http://image.hotrod.com/f/techarticles/engine/9068904+w794/113_0208_v6_13_z.jpg


Look at the dyno chart for this pushrod engine..... I've not looked at any, yet, for the DMC tubular exhausts I've seen so far, but.... what I know just by looking is that none of them (seemingly designed for 10-13,000 rpm) come close to this one's fat and flat torque band as well as amazingly flat HP curve. I can also tell you what is shown in this article and not mentioned is this engine's amazing BSFC numbers, but, what it being pimped here isn't quite the same as what actually ends up in the winner's circles, the more sophisticated cheater stuff that very few ever get to see up close or lay hands upon..... ;-)


Notice this engine is all done at 6000 rpm and it would be very easy to change a few exhaust parameters to rock the curves upwards or downwards. If you've never driven a ride with a BGN V6, you should. The PRV has much more potential (the exhaust ports appear to be miserable) and the best I can tell, the CIS system, with some easy mods, can accommodate 275+ horsepower, normally aspirated, with wider HP and torque curves of the BGN engine, due to it picking up the 2nd, 3rd and 4th pulses and a couple other superior design features.

Does anyone have any interest in designing and fabbing a much more scientifically based header unit, with or without cats? I promise I'm going to build one for my car and wouldn't mind at all sharing with somebody more in a position to replicate and produce multiple units for road or track use.



Now, back to the blower, if you know would you answer what I've asked and also what displacement is the unit used for this application?

I clicked the link and got the naked orange page, didn't see anything specific to the car shown with one, waded through a few pages and couldn't find simple specs or determine if is machined from a casting or billet, much less any other specifics since I'm too lazy to download a PDF of FAQ's even!

Myself, I'd be inclined to sync a three lobed screw with lined tips, most likely a very inexpensive and readily available Eaton unit. Maybe even cleverly as to get some free counter balancing.

I'm not a fan of billet blowers, due to their less than favorable coefficients of expansion. If the lobes are straight... less of a fan for this engine for obvious reasons, if the lobes are billet and especially billet and not tipped with teflon... again even less.


Regardless, the blown car and it's execution is visually very nice. Does it have any dyno sheets or useful track time slips?

Pointed you right to the manufactures site. If they don't post it then I doubt anyone does. It is a sprintex unit. They only have one or two units available and I would suspect it is the smaller one.

On the header system. Too small of a market to redesign. I employed the best in the country to build ours for what we needed.

EarlHickey
05-06-2012, 01:10 PM
Are you toying with me? I don't see a dyno chart, just some peak numbers mentioned.


Dyno info here:

http://dmctalk.org/showthread.php?2530-Stage-I-II-and-III-details-and-pricing

EarlHickey
05-06-2012, 01:21 PM
With all due respect, I've never seen such a poorly designed collector and overall it is one heck of a large OD and very short primary'd header.

Tell me some dimensions and perhaps I'll send you, or bring some next time I'm through that way, a pair of real collectors for you to compare dyno numbers and BSFC numbers.

I've no problem doing a one off for my own use. I plan on keeping this car a very long time. Maybe I'll do five, but, they'd be extremely expensive, especially if 321.

Thanks on the link, it does amaze me that they'd not make it easy to see what they are actually offering.


Pointed you right to the manufactures site. If they don't post it then I doubt anyone does. It is a sprintex unit. They only have one or two units available and I would suspect it is the smaller one.

On the header system. Too small of a market to redesign. I employed the best in the country to build ours for what we needed.

opethmike
05-06-2012, 01:25 PM
Are you toying with me? I don't see a dyno chart, just some peak numbers mentioned.

Toying with you? What's your problem, pal? You asked for info, I gave you what I could. You seem to be treating everybody who's trying to help you in the same rude manner.

EarlHickey
05-06-2012, 01:44 PM
Relax, I didn't see any dyno info at the link at all, only estimated numbers on a for sure five figure price tag. If that doesn't require a sense of humor, I can't think of much that may.

Check out the dyno chart for the V6 BGN I posted, that's the kinda of data, dyno charts and all equipment specs, I would have to see to ever consider laying out that kinda cash. You?


Toying with you? What's your problem, pal? You asked for info, I gave you what I could. You seem to be treating everybody who's trying to help you in the same rude manner.

Delorean Industries
05-06-2012, 03:24 PM
This is quickly becoming a Robertson situation. I'm out of here.

EarlHickey
05-07-2012, 09:44 AM
This is quickly becoming a Robertson situation. I'm out of here.

Whatever that means.......... just trying to help you without sugar coating things.

http://www.burnsstainless.com/RESF.pdf

http://www.burnsstainless.com/Burns_Catalog_Online.pdf

Check out page 20..... that's how it's done.

nofear365
05-07-2012, 10:03 AM
This is quickly becoming a Robertson situation. I'm out of here.

You read my mind!

Kenny_Z
05-10-2012, 12:58 AM
I'm trying to wrap my head around the headers you're talking about building. From what I gather you're talking about taking an exhaust port from the left and having it exit the right collector and vice versa? The tubs would have to pass through the area currently occupied by the crossover pipe but then how do you get the remaining exhaust tubes to equal that length? Anything I imagine has a huge mass of pipes that just doesn't fit in the engine bay. Unless you aren't worrying about the equal length on the tubes running from side to side and the remaining pipes.

I've seen headers like this built for other engines. I want to say either Ford or Dodge, I can't remember exactly. I know they are a pain to install in a bay that would hold an entire Delorean. I couldn't imagine trying to stuff something like that into such a small area while leaving room to reach the oil filter and starter.

Of course I could be completely wrong with my thought process.

stevedmc
05-10-2012, 07:12 AM
This is quickly becoming a Robertson situation. I'm out of here.

If this was Bill he would have either been put on timeout or would have been banned by now. I don't think it's him.

EarlHickey
05-10-2012, 09:59 AM
You're on the right track, however, the idea is to have the leading and lagging slugs, on each bank, hit their respective collector at 120 degrees apart.

This does not require a gt40 flat crank v8 snake display.... nor will such a pipe have equal length primaries. See the bgn header, sans crossovers and note the impressive dyno chart with its amazing torque curve reflecting stellar volumetric efficiency even with heads I can assure you are very mych inferior to the dmc's heads.


How much torque does a normally aspirated four stroke engine make when it attains 100% volumetric efficiency? The answer is an absolute.





I'm trying to wrap my head around the headers you're talking about building. From what I gather you're talking about taking an exhaust port from the left and having it exit the right collector and vice versa? The tubs would have to pass through the area currently occupied by the crossover pipe but then how do you get the remaining exhaust tubes to equal that length? Anything I imagine has a huge mass of pipes that just doesn't fit in the engine bay. Unless you aren't worrying about the equal length on the tubes running from side to side and the remaining pipes.

I've seen headers like this built for other engines. I want to say either Ford or Dodge, I can't remember exactly. I know they are a pain to install in a bay that would hold an entire Delorean. I couldn't imagine trying to stuff something like that into such a small area while leaving room to reach the oil filter and starter.

Of course I could be completely wrong with my thought process.

delornut
05-10-2012, 11:29 AM
Header design in most street applications must cover a wide range of driving applications and end up being a compomise but they're not rocket science either. As a rule of thumb longer pipes give better low end torque while shorter pipes work better for high rpm's. Collector diameters and designs vary depending on displacement along with several other things. The available space for routing the headers figures into the equation and in the end there probably is no perfect way for a header design in the DeLorean that will offer the most at all levels of driving. I know that DMC Houston had their headers designed to match the flow characteristics of their head modifications and cam grinds. I can't speak for the other offerings but I'd guess the differences between them are small for every day driving. I'm not sure what Earl is getting at here as he's offered no details, only generalities that hint at his having a technical backgroud. I'm not knocking him, only wondering where he's going with this.

Bruce Benson



You're on the right track, however, the idea is to have the leading and lagging slugs, on each bank, hit their respective collector at 120 degrees apart.

This does not require a gt40 flat crank v8 snake display.... nor will such a pipe have equal length primaries. See the bgn header, sans crossovers and note the impressive dyno chart with its amazing torque curve reflecting stellar volumetric efficiency even with heads I can assure you are very mych inferior to the dmc's heads.


How much torque does a normally aspirated four stroke engine make when it attains 100% volumetric efficiency? The answer is an absolute.

Kenny_Z
05-10-2012, 02:52 PM
How much torque does a normally aspirated four stroke engine make when it attains 100% volumetric efficiency? The answer is an absolute.

You got me, my brain is already fried with network and IP information. I can't fit anything else in here ;)

I do understand the concept better though. The engine is an air pump and incorrect exhaust flow angles can choke it. Makes sense.

EarlHickey
05-10-2012, 07:15 PM
Header design in most street applications must cover a wide range of driving applications and end up being a compomise but they're not rocket science either. As a rule of thumb longer pipes give better low end torque while shorter pipes work better for high rpm's. Collector diameters and designs vary depending on displacement along with several other things. The available space for routing the headers figures into the equation and in the end there probably is no perfect way for a header design in the DeLorean that will offer the most at all levels of driving. I know that DMC Houston had their headers designed to match the flow characteristics of their head modifications and cam grinds. I can't speak for the other offerings but I'd guess the differences between them are small for every day driving. I'm not sure what Earl is getting at here as he's offered no details, only generalities that hint at his having a technical backgroud. I'm not knocking him, only wondering where he's going with this.

Bruce Benson


From the beginning, I'm sure I stated I don't want or need any catalytic convertors and I can certainly see how having to fit them, which most people would desire and require, would eat up a bit of precious space. I merely asked who offered headers for these cars so I could see for myself if anything offered appeared acceptable. As we agree on them not being rocket science, it doesn't take the eye of a NASA engineer to eyeball one and get real close to seeing for which ranges it's been optimized and how much fuel it will waste in the process of driving conditions outside those operating ranges..... without ever seeing a single dyno chart.

If I were to fit cats, I'd likely just have them in the area the popular systems use for the muffler and use less muffler. I already said I was ok with hooligan sound pressure levels although that's not preferred.


Kenny, at 100% VE, an engine makes 1 ft.lb. of torque per Cubic Inch of Displacement. This is why mere peak numbers only leave out lots of very desirable information for a street driven or even rally type car.