Headers ...
Panoz Paul
11-02-2009, 02:34 PM
Back Again Guys ... Still thinking about next year & more hp / performance ... I believe this subject was covered in a previous tread(s) , but here we go ... Long Tube headers are available from Panoz for $ 1,087 ; has any one made the change w/ supporting dyno & are there any things to watch for ??? I believe I read that they may need to be modified ... BBK has a "shorty" header w/ equal tubes that will bolt in w/ a 8 to 15 hp gain for $ 229 in crome / $ 349 in ceramic ... Any thoughts !!! Thanks / Paul W.:runaround:
NZGTRA17
11-02-2009, 03:53 PM
Back Again Guys ... Still thinking about next year & more hp / performance ... I believe this subject was covered in a previous tread(s) , but here we go ... Long Tube headers are available from Panoz for $ 1,087 ; has any one made the change w/ supporting dyno & are there any things to watch for ??? I believe I read that they may need to be modified ... BBK has a "shorty" header w/ equal tubes that will bolt in w/ a 8 to 15 hp gain for $ 229 in crome / $ 349 in ceramic ... Any thoughts !!! Thanks / Paul W.:runaround:
Paul, just remind us.........your car is a GTRA with a 5.0 engine fitted? What other mods have/are you doing to the engine to go with the possible header mod?
Kel.
Paul, just remind us.........your car is a GTRA with a 5.0 engine fitted? What other mods have/are you doing to the engine to go with the possible header mod?
Kel.
Panoz Paul
11-02-2009, 04:39 PM
I twisted the old 5.0 & purchased a Ford Racing 302 / 340 hp , all forged w/ aluminum heads ... I put a 75 mm Edelbrock T. body w/ a Trick-flow upper , 30 lb injectors & had a chip remapped to match all specs , from cam duration to exhaust dia. It's stronger , but a little disappointed , Ford stated that I could go to 1:7 rockers ... Archers Shop stated that the un-equal tube headers were an issue ... If you can & are interested , google Ford Racing Create Motors , they list all the internals ... Thanks !!! / Paul W.
NZGTRA17
11-02-2009, 08:47 PM
I twisted the old 5.0 & purchased a Ford Racing 302 / 340 hp , all forged w/ aluminum heads ... I put a 75 mm Edelbrock T. body w/ a Trick-flow upper , 30 lb injectors & had a chip remapped to match all specs , from cam duration to exhaust dia. It's stronger , but a little disappointed , Ford stated that I could go to 1:7 rockers ... Archers Shop stated that the un-equal tube headers were an issue ... If you can & are interested , google Ford Racing Create Motors , they list all the internals ... Thanks !!! / Paul W.
Paul, I stuck with the 5.0 that was in the car and coverted over to carb. End result was a 9:1 comp engine with similar head flow (270/210 cfm @ 28" of water) and cam (224/232 degs @ .050 degs) to what is most likely in your combo.
I dyno'ed with the shorty headers and Panoz supplied exhaust when the engine was completed. This resulted in approx 280hp and 300ftlbs of torque at the wheels. By cutting off the exhast on the dyno, rejetting and then re-running we established that the exhaust was restrictive as power climed to 300rwhp with the exhaust lopped off. Very loud though........
I looked at header options and due to cost (I am on the other side of the world) and need to modify the GTS header to suit a 5.0 decided to build my own equal length headers (1 3/4" primaries, 3" collectors merging into a 4" single system down the passenger side of the car). To cut a long story short, these boosted power by approx 10% to max's of 340 rwhp and 335 rwtq.
Whether your combo will yield the same sort of improvement will depend on what the next weakest link in the combo is.
The car is fun to drive at its current power level but to be an outright contender I am curently building up a 347 shortblock to slot in while using all of the other curent engine components (cam heads headers etc).
Kel.
Paul, I stuck with the 5.0 that was in the car and coverted over to carb. End result was a 9:1 comp engine with similar head flow (270/210 cfm @ 28" of water) and cam (224/232 degs @ .050 degs) to what is most likely in your combo.
I dyno'ed with the shorty headers and Panoz supplied exhaust when the engine was completed. This resulted in approx 280hp and 300ftlbs of torque at the wheels. By cutting off the exhast on the dyno, rejetting and then re-running we established that the exhaust was restrictive as power climed to 300rwhp with the exhaust lopped off. Very loud though........
I looked at header options and due to cost (I am on the other side of the world) and need to modify the GTS header to suit a 5.0 decided to build my own equal length headers (1 3/4" primaries, 3" collectors merging into a 4" single system down the passenger side of the car). To cut a long story short, these boosted power by approx 10% to max's of 340 rwhp and 335 rwtq.
Whether your combo will yield the same sort of improvement will depend on what the next weakest link in the combo is.
The car is fun to drive at its current power level but to be an outright contender I am curently building up a 347 shortblock to slot in while using all of the other curent engine components (cam heads headers etc).
Kel.
Blue Streak 21
11-02-2009, 10:06 PM
I'm facing the same quandry. I wonder if the long tubes are worth the investment. If they have the same gains on a 347 motor I will be impressed, and that would make them worth the $1 K. I built a 347 last off season. It has alum heads from Canfield (didn't flow them as they are ported), 30 lb injectors, 75 mm TB, and an Typhoon intake. The cam is a custom grind with .55 lift and ...(damned if I can remember the duration). Currently the motor makes 315 rwhp and 350 rwtq.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
NZGTRA17
11-02-2009, 10:15 PM
I'm facing the same quandry. I wonder if the long tubes are worth the investment. If they have the same gains on a 347 motor I will be impressed, and that would make them worth the $1 K. I built a 347 last off season. It has alum heads from Canfield (didn't flow them as they are ported), 30 lb injectors, 75 mm TB, and an Typhoon intake. The cam is a custom grind with .55 lift and ...(damned if I can remember the duration). Currently the motor makes 315 rwhp and 350 rwtq.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
Peak torque is at 4750rpm and peak power is at 5700rpm. To keep these peak rpm levels the same in the 347 my intention at this stage is to use the same cam but retard the cams timing by 4 degs (or more as required).
One thing that I didnt say is that the header pipe sizes and lengths were configured for a 347 so in theory were not ideal for a 302/5.0. Likewise all other major engine components (heads cam etc) were specced to be beter suited to a 347 as this was where I intended to be in the future. It will be very interesting to see how the 347 goes in comparison to the 302.
Kel.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
Peak torque is at 4750rpm and peak power is at 5700rpm. To keep these peak rpm levels the same in the 347 my intention at this stage is to use the same cam but retard the cams timing by 4 degs (or more as required).
One thing that I didnt say is that the header pipe sizes and lengths were configured for a 347 so in theory were not ideal for a 302/5.0. Likewise all other major engine components (heads cam etc) were specced to be beter suited to a 347 as this was where I intended to be in the future. It will be very interesting to see how the 347 goes in comparison to the 302.
Kel.
jmimac351
11-02-2009, 10:27 PM
Paul, when I spoke to PAD about a month ago about headers they no longer had them. Apparently their supplier requires an order of 10 units to produce and I'm not sure whether they planned to have any more made. If they had some demand I'm sure they'd have them made.
NZGTRA17
11-02-2009, 10:38 PM
I'm facing the same quandry. I wonder if the long tubes are worth the investment. If they have the same gains on a 347 motor I will be impressed, and that would make them worth the $1 K. I built a 347 last off season. It has alum heads from Canfield (didn't flow them as they are ported), 30 lb injectors, 75 mm TB, and an Typhoon intake. The cam is a custom grind with .55 lift and ...(damned if I can remember the duration). Currently the motor makes 315 rwhp and 350 rwtq.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
Jerry, happy to send you an excel graph of the dyno results. If this will help, PM me your E address and I will send.
Kel.
I supose that the larger displacement motor will cause the exhaust to be even more restrictive, hence the long tubes are even more worth while.
Kel, did the headers stretch your peak torque to higher rpms or flatten your torque curve? My torque curve peaks at 3750 rpm and drops off pretty quickly. I think my torque curve is a cam issue, but if the long tubes can help there, I'll stick with the cam I have for another year.
Jerry, happy to send you an excel graph of the dyno results. If this will help, PM me your E address and I will send.
Kel.
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