Just found some HM headers on eBay but they are for an AWD 3.5 are these different to FWD ones?

Also how do HM compare as to quality and performance compared to Pacemaker and others?

hm headers are the same design as the ralliart. The gains wont be as much as a set of pacemakers or hurricane headers, because they are only a short primary design. As far as i know headers for the AWD models make a sharp turn to clear the driveline, and are a bit more restrictive than the FWD.

yeah the AWD and FWD headers are different and are not interchangeable.
i dont think that their is a problem with the quality of them at alll, but for the price that their prob listed on ebay you would be able to get a set of paccies, or dare i say it, rpw ones..

The only difference b/w the FWD and AWD headers (from close physical inspection) is that the rear back makes a circular bend for the AWD whereas the FWD makes a rounded-corner-rectangular bend. The reason for this is for the AWD pipe work to clear the diff or something like that. Restriction wise, there is no difference. The restriction in the AWD is in the stock header which makes a very sharp 180 degrees bend.
See the attachments:

I have HM headers installed on my FWD. They will bolt straight on to your car. They are a good quality. You can read about them on their web site HERE (http://www.hmheaders.com.au/).

I saw my local exhaust bloke and he said he can do Paccies for about $700 fitted, so i might go that way as most on here seem to like them.

That sound like a very good price, for a nice set of headers and fitted too,I'd go for it.

Cheers Dave.

Hurricanes if you want to go FI - just for the larger primary pipes. Pacemakers give excellent NA results as will the Hurricanes. Ignore Wildcat/Genie and HM. The pacies and hurris both have almost equal length primaries, the pacies would be my pick for NA and some FI applications too. :cool:

Hurricanes if you want to go FI - just for the larger primary pipes. Pacemakers give excellent NA results as will the Hurricanes. Ignore Wildcat/Genie and HM. The pacies and hurris both have almost equal length primaries, the pacies would be my pick for NA and some FI applications too. :cool:

Thanks mate, unless someone drops a whole bunch of cash that happens to land in my pocket my car will stay NA, for a while atleast.

So sounds like paccies are definatly the go.

Thanks mate, unless someone drops a whole bunch of cash that happens to land in my pocket my car will stay NA, for a while atleast.

So sounds like paccies are definatly the go.

That's what I'd do for sure. ;)

Yeah EZ Boys right on the money the pacemakers will support most N/A applications and the're good value.

Cheers Dave.

Yeah EZ Boys right on the money the pacemakers will support most N/A applications and the're good value.

Cheers Dave.

definately. The a mate of mine got pacemakers, a radiator mounted air intake and a factory 'power chip' on his vy SS commo. The power difference was absolutely amazing. not to mention the sound

i know a 5.7 v8 is a bit different to a magna engine.... but that set seems to be the best bang for your buck non turbo mod. I'm using the ss as an example since i havent experienced a magna before/after. but i swear by the effectiveness of pacemaker headers.

When Ralliart run the AWD Magnas in Aust Rally Championship they used HM headers. The short primary pipes only reduce low speed torque if the secondary pipes are short. HM have been around a long time and do custom exhaust work for the car makers. When Bathurst was for production cars HM did the headers for all the factory "specials" from Holden, Ford, Chrysler. Originally they were named Head Mod.

Long primary pipes don't help low speed unless the secondary pipes are made longer to compensate. Long primary pipes have more volume and so have a weaker pulse at low rpm.

The basic rule is short primaries and long secondaries for low speed power and long primaries and short secondaries(or no secondaries) for more high rpm power.

Headers help the AWD pick up 5-6kw because of the restrictive join for the rear bank. For FWD 3rd gen there isn't much gain as the rear bank join is quite good and flows well. Ralliart said power only went from 178kw to 180kw on the Ralliart engine when they added HM headers so if they only got 2kw with a modified engine a standard engine with stock heads, cams and compression isn't going to gain much. 2nd gen Magnas have a rear bank join like the AWD so headers help.

When Ralliart run the AWD Magnas in Aust Rally Championship they used HM headers. The short primary pipes only reduce low speed torque if the secondary pipes are short. HM have been around a long time and do custom exhaust work for the car makers. When Bathurst was for production cars HM did the headers for all the factory "specials" from Holden, Ford, Chrysler. Originally they were named Head Mod.

Long primary pipes don't help low speed unless the secondary pipes are made longer to compensate. Long primary pipes have more volume and so have a weaker pulse at low rpm.

The basic rule is short primaries and long secondaries for low speed power and long primaries and short secondaries(or no secondaries) for more high rpm power.

Headers help the AWD pick up 5-6kw because of the restrictive join for the rear bank. For FWD 3rd gen there isn't much gain as the rear bank join is quite good and flows well. Ralliart said power only went from 178kw to 180kw on the Ralliart engine when they added HM headers so if they only got 2kw with a modified engine a standard engine with stock heads, cams and compression isn't going to gain much. 2nd gen Magnas have a rear bank join like the AWD so headers help.

Hi Alan, welcome to the club,you sound like you may be ex MMAL or similar ?

When Ralliart run the AWD Magnas in Aust Rally Championship they used HM headers. The short primary pipes only reduce low speed torque if the secondary pipes are short. HM have been around a long time and do custom exhaust work for the car makers. When Bathurst was for production cars HM did the headers for all the factory "specials" from Holden, Ford, Chrysler. Originally they were named Head Mod.

Long primary pipes don't help low speed unless the secondary pipes are made longer to compensate. Long primary pipes have more volume and so have a weaker pulse at low rpm.

The basic rule is short primaries and long secondaries for low speed power and long primaries and short secondaries(or no secondaries) for more high rpm power.

Headers help the AWD pick up 5-6kw because of the restrictive join for the rear bank. For FWD 3rd gen there isn't much gain as the rear bank join is quite good and flows well. Ralliart said power only went from 178kw to 180kw on the Ralliart engine when they added HM headers so if they only got 2kw with a modified engine a standard engine with stock heads, cams and compression isn't going to gain much. 2nd gen Magnas have a rear bank join like the AWD so headers help.

It is refreshing to see someone who also knows his stuff. We are far and few amongst us here me thinks. Welcome.

Yes HM have been around for years, my 68 Fairmont Wagon has them and they are a very good fit especially around the steering box which is an issue in the older Fords.

I have fitted all sorts including those ones from the western states that hit the floor pan, I do prefer Pacemakers over most but HM are fairly high up the list. The only shame really is that people do not make a shorter set for the 3.0 as the 10mm or so makes a huge difference when you are lowering. Is a bigger shame that no one makes 2nd gen ones either as the std pipe set up, like the AWD is horrible

I saw my local exhaust bloke and he said he can do Paccies for about $700 fitted, so i might go that way as most on here seem to like them.

Hmmm that seems a little too much just for pacemakers supplied and fitted. Mine was the same price with additional 2.5 inch flex piping and an exhaust tip supplied and fitted.

Hmmm that seems a little too much just for pacemakers supplied and fitted. Mine was the same price with additional 2.5 inch flex piping and an exhaust tip supplied and fitted.
Too much? Man I was quoted $1,100 for pacies supplied and fitted! THAT is too much.

Is a bigger shame that no one makes 2nd gen ones either as the std pipe set up, like the AWD is horrible

:noway: For real? No 2nd Gen extractors? I've got the remains of what appears to be Hurricanes I was given by Killbilly before his DOHC converstion.

So that's a definate? Is there actually any demand? Might give me something to do.

@EZ BOy: I would be interested in a set for 2nd gen, but what would the power gains be like.....? to me $700 is a bit much for only a couple of killerwasps

I got quoted $825 to get some pacies fitted today... I think it would be a little steep. They are $475 retails so they would get them at trade price, so they are making at least $400 on labour which is plain stupid.

It is refreshing to see someone who also knows his stuff. We are far and few amongst us here me thinks. Welcome.

Yes HM have been around for years, my 68 Fairmont Wagon has them and they are a very good fit especially around the steering box which is an issue in the older Fords.

I have fitted all sorts including those ones from the western states that hit the floor pan, I do prefer Pacemakers over most but HM are fairly high up the list. The only shame really is that people do not make a shorter set for the 3.0 as the 10mm or so makes a huge difference when you are lowering. Is a bigger shame that no one makes 2nd gen ones either as the std pipe set up, like the AWD is horrible

That is why D&T here in Adelaide retro-fitted the y-pipe from a 3rd gen Sports to my old KS. No more T-Junctions.

:noway: For real? No 2nd Gen extractors? I've got the remains of what appears to be Hurricanes I was given by Killbilly before his DOHC converstion.

So that's a definate? Is there actually any demand? Might give me something to do.

These were supplied by Dave Thomas and then given to KB. Within weeks of fitting they cracked. Dave "advised" everyone that these were HIS custom design. I would also believe it because as with everything RPW, they lasted 5 minutes and then fell apart.

I believe they were made in some joint in Sydney but were not Hurricane. The trouble over several months that KB had with getting Thomas to do anything was unreal as KB had to do all of the chasing around and follow up. Not bad for a product you buy hey


I got quoted $825 to get some pacies fitted today... I think it would be a little steep. They are $475 retails so they would get them at trade price, so they are making at least $400 on labour which is plain stupid.

Fitting is about 2 - 3 hours tops including having to cut the flex pipe off the original engine pipe and weld onto the pacies. Some shops will use a new flex pipe and flange so may be worth finding out if this includes this

lol nuf said.

Most posters have ignored the original post - they make a FWD version as well



Just found some HM headers on eBay but they are for an AWD 3.5 are these different to FWD ones?


Also how do HM compare as to quality and performance compared to Pacemaker and others?

Most posters have ignored the original post - they make a FWD version as well,

http://cgi.ebay.com.au/Magna-TF-TW-FWD-3-5-V6-HM-Headers-Extractors_W0QQitemZ140304055382QQihZ004QQcategory Z130631QQtcZphotoQQcmdZViewItemQQ_trksidZp1713.m15 3.l1262

Thanks for the welcome Zero. To answer your question - No never worked with any car maker specifically. Nearly 50 years since I built my first engine and nearly as long consulting to manufacturers, OEMs, race & rally car and bike teams.

Have added some pictures to illustrate the problem with Magna exhaust on 2nd gen and 3rd gen AWD.

Pic 1- The 2nd gen Magna had a really restrictive rear bank join. It doesn't need headers to fix the problem. A new rear pipe and collector will do nicely. With a split exhaust headers are only much use with a pretty big cam. Save your money, just run the pipes as was done on the 3rd gen.

Pic 2 - Mitsu got it pretty close with the 3rd gen Magna. The collector can be improved but its not too bad.

Pic 3 - HM AWD header join. The HM FWD 3rd gen header is similar. Good flowing join as it should have been done by Mitsu but a waste spending money on headers for the 3rd gen FWD.

Cheers, Alan

Thanks Alan (great to see another older generation member not apparently too concerned with audio/visual and appearances over value for $ performance), after pricing Hurricanes (astronomical), reading every posting I could find and PMs with a number of members whose advice I value highly (Chisholm, EZ Boy, Madmagna, Magna00, Vlad, Zero*) you have helped me make up my mind to get the HM version for my TL AWD VRX which I intend to fit with the EZ Boy SF inlet manifold & Flowed TB, Microtech piggyback ECU, RPW stage 2 auto cams & valve springs, 10:1 Pajero pistons, hiflow cat, CAI etc.

$495 delivered with confirmed fitment under 2 hours (thanks Vlad) and a Fulcrum suspension and exhaust place in Tuggeranong (ACT) that seems to provide reasonable prices ($99 hour labour) and service without the ripoff attitude/disinterest in fitting 'non supplied' systems.

Alan do you actually have a set of the HM AWD headers as it appears to be a private photo? Do you know if they are coated with anything or just left wiith the Stainless Steel surface (it looks a little too matt for just S/S)?

(* see Zero if you were called Alpha you could have been first on my list)

AWWW..SHUCKS..:thumbsup:

Thanks Alan (great to see another older generation member not apparently too concerned with audio/visual and appearances over value for $ performance), after pricing Hurricanes (astronomical), reading every posting I could find and PMs with a number of members whose advice I value highly (Chisholm, EZ Boy, Madmagna, Magna00, Vlad, Zero*) you have helped me make up my mind to get the HM version for my TL AWD VRX which I intend to fit with the EZ Boy SF inlet manifold & Flowed TB, Microtech piggyback ECU, RPW stage 2 auto cams & valve springs, 10:1 Pajero pistons, hiflow cat, CAI etc.

$495 delivered with confirmed fitment under 2 hours (thanks Vlad) and a Fulcrum suspension and exhaust place in Tuggeranong (ACT) that seems to provide reasonable prices ($99 hour labour) and service without the ripoff attitude/disinterest in fitting 'non supplied' systems.

Alan do you actually have a set of the HM AWD headers as it appears to be a private photo? Do you know if they are coated with anything or just left wiith the Stainless Steel surface (it looks a little too matt for just S/S)?

(* see Zero if you were called Alpha you could have been first on my list)

Its coated. Once fitted, the engine needs to idle for a few minutes (can't remember exactly how long) so that the enamel heat coating will set, so to speak. It'll give off a lot of smoke.

Hi Gang,

I've got some of the HMs from ebay for my TW awd vrx. No manifold gaskets were supplied, but I do have some new metal stock gaskets in the shed. What is recommended, gaskets, or no gaskets, and any preferred jointing compound? I would probably go with the gasket and some VHT copper spray gasket, but what do the experts suggest?

Thanks
Steve

stocky metal ones on mine.

Hi Gang,

I've got some of the HMs from ebay for my TW awd vrx. No manifold gaskets were supplied, but I do have some new metal stock gaskets in the shed. What is recommended, gaskets, or no gaskets, and any preferred jointing compound? I would probably go with the gasket and some VHT copper spray gasket, but what do the experts suggest?

Thanks
Steve
Read the information from the link I posted in post #5, your questions are already answered...FOLLOW THE LINK HERE (http://www.hmheaders.com.au/index.php?q=Technical-Info.html), and in case you cant be bothered to go there, .... you don't need gaskets, and use only non-silicon based compound....

Thanks Alan (great to see another older generation member not apparently too concerned with audio/visual and appearances over value for $ performance), after pricing Hurricanes (astronomical), reading every posting I could find and PMs with a number of members whose advice I value highly (Chisholm, EZ Boy, Madmagna, Magna00, Vlad, Zero*) you have helped me make up my mind to get the HM version for my TL AWD VRX which I intend to fit with the EZ Boy SF inlet manifold & Flowed TB, Microtech piggyback ECU, RPW stage 2 auto cams & valve springs, 10:1 Pajero pistons, hiflow cat, CAI etc.

$495 delivered with confirmed fitment under 2 hours (thanks Vlad) and a Fulcrum suspension and exhaust place in Tuggeranong (ACT) that seems to provide reasonable prices ($99 hour labour) and service without the ripoff attitude/disinterest in fitting 'non supplied' systems.

Alan do you actually have a set of the HM AWD headers as it appears to be a private photo? Do you know if they are coated with anything or just left wiith the Stainless Steel surface (it looks a little too matt for just S/S)?

(* see Zero if you were called Alpha you could have been first on my list)

There painted a matte silver paint, that has stayed that way since I have installed it now for 4 months now.

... but a waste spending money on headers for the 3rd gen FWD.


Why???

Hi Gang,

I've got some of the HMs from ebay for my TW awd vrx. No manifold gaskets were supplied, but I do have some new metal stock gaskets in the shed. What is recommended, gaskets, or no gaskets, and any preferred jointing compound? I would probably go with the gasket and some VHT copper spray gasket, but what do the experts suggest?

Thanks
Steve

You can reuse the stock metal gaskets in 99% of cases unless there are problems with it, the studs or other dramas. You can put a bead of exhaust sealant around the gasket (both sides) but it's rarely needed. Just remember to tension the nuts from the centre of the header flange to the outside of the flange - as it you were smoothing the wrinkles out of a bedsheet (if you follow).

If you don't have a hoist, do a 'loose' fit first to ensure the cat to secondary pipes lines up ok and there's no stress in the flex joint etc. Have fun. Oh yeah - best to do on a COLD car. :D

Hi Gang,

I've got some of the HMs from ebay for my TW awd vrx. No manifold gaskets were supplied, but I do have some new metal stock gaskets in the shed. What is recommended, gaskets, or no gaskets, and any preferred jointing compound? I would probably go with the gasket and some VHT copper spray gasket, but what do the experts suggest?

Thanks
Steve

As advised by GTVi the HM site states

"Headers - Do not fit gaskets!

(Unless the vehicle has aluminium cylinder heads or is a non-cross flow configuration.)

Fitting instructions advise the installer not to fit gaskets to nearly 80% of the product range. This is due to the extremely high standard to which all HM Headers header flanges are manufactured. The use of an appropriate sealant on all flange faces is all that is required for a successful header installation.

This "no gasket" policy is valid for all V8, V6 and cross flow 4 and 6 cylinder engines. With non-cross flow engines the fitting of an exhaust manifold gasket is advised for the sake of sealing the inlet manifold.

If a gasket is required to be fitted, Use an original equipment gasket or a quality after market product.

"If I don't have to fit gaskets, what type of sealant should I use?"

Do not use a silicone base sealer of any type in front of your O2 sensor or Catalytic converter.

We recommend the use of an automotive grade product for sealing all flange faces. Ordinary automotive grade paste is able to withstand the high temperatures generated at the exhaust port of an engine and is less likely to "blow out" and begin leaking like some silicone exhaust sealers can do.

When fitting a set of headers to a vehicle with a catalytic converter and oxygen sensor, it is recommended that the installer does not use a silicone product which if used incorrectly can damage or poison the cat or oxygen sensor. There are several brands of quality non-silicone pastes available from local auto parts suppliers.

Once the header installation is complete, do not immediately start and rev the engine. This could lead to "blowing out", as the sealant would not be cured. If the vehicle needs to be driven as soon as the header is installed, start the engine and let it idle for 2-3 minutes. The exhaust heat from the idling engine will help speed up the curing process without the risk. "

Thank god I didn't poison my cat. :roll: lol

Regarding the use of RTV silicone sealants remember there are some that are not CAT safe eg. Silastic. Many RTVs are CAT safe and marked as being OK. Generally these are blue coloured.

Heat is not usually an issue with RTV for sealing exhausts. I have used it for 30 years and its my preferred exhaust sealant. If you check the packaging you can see what temps each grade of RTV will handle continuously. I only ever use CAT safe blue. Mostly the RTV is not subjected to direct exhaust flame; it only gets heat transferred through the metal of the cylinder head and flanges, etc. and that is well under what RTV will handle.

Many race engines, 2 stroke and 4 stroke, don't have bolted up exhausts but use slip joints and springs. The way these joints are kept from leaking and ensuring proper pulsing is to seal them with RTV.

Cheers,
Alan

Sorry forgot to add details about temps that are OK with ordinary CAT safe/sensor safe RTV silicone.

I checked my Loctite Blue MAXX pack and it says 260 deg C. Some specialised stuff will go higher but often isn't sensor safe.

Cheers, Alan

When you receive your HM Headers, ensure you reweld the flanges that bolt to the engine head and then die grind the old welds flat. For some stupid reason the welds are on the INSIDE of the piping, restricting flow. Pretty piss poor in my opinion.

When you receive your HM Headers, ensure you reweld the flanges that bolt to the engine head and then die grind the old welds flat. For some stupid reason the welds are on the INSIDE of the piping, restricting flow. Pretty piss poor in my opinion.

Yeah my R.P.W.s were welded inside & out at the flanges',so I smoothed out the inner ones.

Thanks for the advice re gaskets, I shall install them as soon as I get thew time in the next few weeks, perhaps over Easter.

Cheers
Steve