Hi everybody,
I´m the guy with the 388 Chevy engine in my wifes 79 Mustang. We have the Edelbrock Pro Flo XT Intake
and E-Tech200 heads and a compression of 11.8 : 1.
Cam is solid roller 236/236 @ 0.050" 0.55 lift.
After changing the headers the car ran 12.4 and 112 mph which is about 0.6 sec better than before.
BUT it seems No one exept us uses this Intake for power. There was an article in a magazine about fuel savings with the XT and thats it. Silence about this intake. is it possible that this intake is the wrong one exept for looks?
Are there dyno tests with intake swaps?
heres are some pictures of the engine
(i hope someone answers despite the fact that the car is no Chevy...)
http://davidpower.de/referenzen_mustang.html#
the 200cc e-tec heads easily support 500 hp on an 11.8:1 compression 383, but obviously the cars gearing and converter stall or manual trans gearing must match the engines power band.
don,t guess, do some tests and locate the problem.
I can,t read the linked info so please post this info requested below.
So Id need to know the tire diameter, rear gear ratio car weight and drive train gearing and type of transmission,,Id like to know what a dyno shows your fuel air ratio, ignition timing and plenum vacuum readings are and what your exhaust back pressure is, Id like to know what cam your using,MANUFACTURERS PART NUMBER ETC. what rocker ratio?,, its lift, LSA and duration at .050 lift, as I suspect your a bit under cammed, most solid roller cams have more lift and duration, for that application so I can do a bit of software dyno test builds.
Id like to know what valve springs you used, the standard valve springs that cam with the heads are not designed for roller lifters.
Id like to know what your fuel pressure is and what your injector flow rate is.
if I know those factors I can pretty much find out if the intakes restrictive.
http://www.edelbrock.com/automotive_new ... rpm1.shtml
http://www.superchevy.com/technical/eng ... 08sc_mm05/
Thanks for the info.
I will make tests concerning backpressure and manifold vacuum.
One thing I know for sure is my air cleaner is a bit restrictive and the headers and the 2.5" "tailpipe" may be a bit too small but space is really limited . We use the car for Oldtimer rallies also where you got lots of driving very slow and standing in a row waiting for the next
excercise. That makes a lot of thermal problems
for us .It gets really hot in summer with engine idle at 900 and standing around. So its the problem to have a °historic" car that could be used for oldtimer purposes and 1/4 mile racing too.
We wanted around 400 hp and 12.4 s 112 mph in a
car with driver that has 3300 pounds seems to fit.
But again to get to the proflo xt manifold:
The ports seem a bit restrictive. The injector bungs protruded way too far into the ports so i had to grind around a bit. And in my opinion the ports are relative small. And they absolutely don´t fit the E-tech inlets. Inlets of heads are rectangular, ports of manifold are vortec-like less wide in the upper part.And the widest part of the manifold port is about 1/10" smaller than the E-tech inlet. Read about a guy who port matched this intake and had to epoxy the outer manifold walls because he grinded holes .And thats exactly
how the manifold looks like.
Thats why my question came up : is this Manifold
junk for the E-tech heads althoug Edelbrock combines those two?
I´m sorry if my links didn´t work.
my homepage is http://www.Davidpower.de
The engine is seen on the mustang side. No need to read this strange language, just click the pics.
Theres one 1/8mile video of the car showing how bad it hooks.
In my opinion, your faced with a rather common situation where theres no easily available, direct replacement intake manifold, with significantly larger ports to match those e-tech /vortec style heads.
but Id like to see the test results before you go assuming its the intake thats the huge restriction, it might be the exhaust flow is a big restriction,or the engines cam timing not allowing the engine to breath,of a fuel supply issue, you can,t assume its the intake allone causing the lack of power it could easily be several factors in combination.
your probably aware there are intakes with larger ports, of a totally different design, that would require a new throttle body.
http://www.edelbrock.com/automotive_new ... hevy.shtml
If the testing indicates the intake manifold is restricting power, the most cost effective route would be to have extra aluminum material TIG welded to your current runners and allow you to port them to match the current heads port opening, and while that sounds like a great deal of trouble its something any decent automotive performance machine shop can do for you, if you don,t personally have the tools and skills
I don,t know anyone whos done enough testing with that intake yet to give a definitive answer,it may or may not be able too provide you with the flow rates required, but I would not just write it off as a complete failure without further testing.
many guys just start swapping parts rather than do some testing to determine the CAUSE of a problem, looking for a quick fix, because its far easier to swap parts than to diagnose exactly whats going on and how to best correct some issue, and while that might be the easy solution its not cheap or always the best route.
if your determined to swap intakes, and if it was my car and I was concerned with the engines potential power Id select a well ported holley stealth ram, like I did on my engine.but I ported the intake extensively and fabricated a custom plenum, so you might as well port your current intake and if that requires changes you might consider your options
but Ive got a feeling that you might have significant gains available with a change in the cars converter stall speed, rear gear ratio and maybe a different cam and larger injectors, and a less restrictive exhaust, headers that scavenge efficiently aid intake flow rates when matched to a cam timing that allows the exhaust inertia to drag in the intake charge in the intake runners
read the links
viewtopic.php?f=55&t=1745&p=4378&hilit=stealth+ram#p4378
viewtopic.php?f=32&t=430
viewtopic.php?f=52&t=333
viewtopic.php?f=52&t=322
RELATED THREADS
viewtopic.php?f=52&t=462
viewtopic.php?f=52&t=5154
viewtopic.php?f=55&t=1052&p=26611&hilit=EDELBROCK+Pro+Flo#p26611
viewtopic.php?f=55&t=5175&p=25996&hilit=tunnel#p25996
viewtopic.php?f=55&t=431&p=23660&hilit=stealth+ram#p23660
viewtopic.php?f=55&t=444
viewtopic.php?f=55&t=1231&p=19119&hilit=selecting+injectors#p19119
viewtopic.php?f=55&t=5503&p=18605&hilit=selecting+injectors#p18605
I´m the guy with the 388 Chevy engine in my wifes 79 Mustang. We have the Edelbrock Pro Flo XT Intake
and E-Tech200 heads and a compression of 11.8 : 1.
Cam is solid roller 236/236 @ 0.050" 0.55 lift.
After changing the headers the car ran 12.4 and 112 mph which is about 0.6 sec better than before.
BUT it seems No one exept us uses this Intake for power. There was an article in a magazine about fuel savings with the XT and thats it. Silence about this intake. is it possible that this intake is the wrong one exept for looks?
Are there dyno tests with intake swaps?
heres are some pictures of the engine
(i hope someone answers despite the fact that the car is no Chevy...)
http://davidpower.de/referenzen_mustang.html#
the 200cc e-tec heads easily support 500 hp on an 11.8:1 compression 383, but obviously the cars gearing and converter stall or manual trans gearing must match the engines power band.
don,t guess, do some tests and locate the problem.
I can,t read the linked info so please post this info requested below.
So Id need to know the tire diameter, rear gear ratio car weight and drive train gearing and type of transmission,,Id like to know what a dyno shows your fuel air ratio, ignition timing and plenum vacuum readings are and what your exhaust back pressure is, Id like to know what cam your using,MANUFACTURERS PART NUMBER ETC. what rocker ratio?,, its lift, LSA and duration at .050 lift, as I suspect your a bit under cammed, most solid roller cams have more lift and duration, for that application so I can do a bit of software dyno test builds.
Id like to know what valve springs you used, the standard valve springs that cam with the heads are not designed for roller lifters.
Id like to know what your fuel pressure is and what your injector flow rate is.
if I know those factors I can pretty much find out if the intakes restrictive.
http://www.edelbrock.com/automotive_new ... rpm1.shtml
http://www.superchevy.com/technical/eng ... 08sc_mm05/
Thanks for the info.
I will make tests concerning backpressure and manifold vacuum.
One thing I know for sure is my air cleaner is a bit restrictive and the headers and the 2.5" "tailpipe" may be a bit too small but space is really limited . We use the car for Oldtimer rallies also where you got lots of driving very slow and standing in a row waiting for the next
excercise. That makes a lot of thermal problems
for us .It gets really hot in summer with engine idle at 900 and standing around. So its the problem to have a °historic" car that could be used for oldtimer purposes and 1/4 mile racing too.
We wanted around 400 hp and 12.4 s 112 mph in a
car with driver that has 3300 pounds seems to fit.
But again to get to the proflo xt manifold:
The ports seem a bit restrictive. The injector bungs protruded way too far into the ports so i had to grind around a bit. And in my opinion the ports are relative small. And they absolutely don´t fit the E-tech inlets. Inlets of heads are rectangular, ports of manifold are vortec-like less wide in the upper part.And the widest part of the manifold port is about 1/10" smaller than the E-tech inlet. Read about a guy who port matched this intake and had to epoxy the outer manifold walls because he grinded holes .And thats exactly
how the manifold looks like.
Thats why my question came up : is this Manifold
junk for the E-tech heads althoug Edelbrock combines those two?
I´m sorry if my links didn´t work.
my homepage is http://www.Davidpower.de
The engine is seen on the mustang side. No need to read this strange language, just click the pics.
Theres one 1/8mile video of the car showing how bad it hooks.
In my opinion, your faced with a rather common situation where theres no easily available, direct replacement intake manifold, with significantly larger ports to match those e-tech /vortec style heads.
but Id like to see the test results before you go assuming its the intake thats the huge restriction, it might be the exhaust flow is a big restriction,or the engines cam timing not allowing the engine to breath,of a fuel supply issue, you can,t assume its the intake allone causing the lack of power it could easily be several factors in combination.
your probably aware there are intakes with larger ports, of a totally different design, that would require a new throttle body.
http://www.edelbrock.com/automotive_new ... hevy.shtml
If the testing indicates the intake manifold is restricting power, the most cost effective route would be to have extra aluminum material TIG welded to your current runners and allow you to port them to match the current heads port opening, and while that sounds like a great deal of trouble its something any decent automotive performance machine shop can do for you, if you don,t personally have the tools and skills
I don,t know anyone whos done enough testing with that intake yet to give a definitive answer,it may or may not be able too provide you with the flow rates required, but I would not just write it off as a complete failure without further testing.
many guys just start swapping parts rather than do some testing to determine the CAUSE of a problem, looking for a quick fix, because its far easier to swap parts than to diagnose exactly whats going on and how to best correct some issue, and while that might be the easy solution its not cheap or always the best route.
if your determined to swap intakes, and if it was my car and I was concerned with the engines potential power Id select a well ported holley stealth ram, like I did on my engine.but I ported the intake extensively and fabricated a custom plenum, so you might as well port your current intake and if that requires changes you might consider your options
but Ive got a feeling that you might have significant gains available with a change in the cars converter stall speed, rear gear ratio and maybe a different cam and larger injectors, and a less restrictive exhaust, headers that scavenge efficiently aid intake flow rates when matched to a cam timing that allows the exhaust inertia to drag in the intake charge in the intake runners
read the links
viewtopic.php?f=55&t=1745&p=4378&hilit=stealth+ram#p4378
viewtopic.php?f=32&t=430
viewtopic.php?f=52&t=333
viewtopic.php?f=52&t=322
RELATED THREADS
viewtopic.php?f=52&t=462
viewtopic.php?f=52&t=5154
viewtopic.php?f=55&t=1052&p=26611&hilit=EDELBROCK+Pro+Flo#p26611
viewtopic.php?f=55&t=5175&p=25996&hilit=tunnel#p25996
viewtopic.php?f=55&t=431&p=23660&hilit=stealth+ram#p23660
viewtopic.php?f=55&t=444
viewtopic.php?f=55&t=1231&p=19119&hilit=selecting+injectors#p19119
viewtopic.php?f=55&t=5503&p=18605&hilit=selecting+injectors#p18605