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How does the heat shield work? Headers look great!
the heat shield seems to work well. It is a '69- i run it hard without both of the dual boosters and it brakes well so i guess it is fine. I have the fancy, centerline, wilwood front brake set-up (6/lb per wheel less unsprung weight!) which offers excellent stopping power. If you want to have the boosters (a must for the originality police) then it may be a tough fit. I have had a '69 with the 2 boosters and the current one without any. I notice no difference between pedal feel and stopping power from either set up. With brakes, it seems to me, it is best to have fewer points of failure...
 

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for TS: if you only want to do it for sound: don`t.... There are more easy ways to get a nice sound, and headers do not contribute that much in total.
 

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Spreull 2mm overbore apple bite pistons with the associated liners, spreull aluminum flywheel, 12mm alfaholics cams, ported head, 40 DCOE's, velocity stacks with ITG filter (don't know about performance gains over stock intake but looks and sounds really good...)
Woosh! VERY NICE!

for TS: if you only want to do it for sound: don`t.... There are more easy ways to get a nice sound, and headers do not contribute that much in total.
*Partially* disagree on that blanket statement, kind sir. Primary lengths do alter the sound significantly, and so does overall header configuration (4 to 1, 4-2-1, etc...)

I bet a Spruell header (equal length 4-2-1) sounds different from a Sperry (equal length 4 to 1), which sounds different from a Shankle/Centerline/Vick's/Alfaholics (slightly unequal length 4 to 1.)
 

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Agree on the "sound" portion in regards to headers.
Alfa's original cast iron headers are sequenced with the firing order so that alternate pulses come out of the two branches and it generates that unique Alfa pulsating sound when an exhaust system is set up right.
My GTV has the cast iron headers, an Abarth front resonator, a Centerline Magnaflow center muffler and Centerline's stinger. Sounds fantastic and it isn't too loud. My duetto is about to get an identical set up.
 

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Ports 1&4 and 2&3 are always paired in 4-2-1 headers so that the pressure pulses in them are evenly spaced. That is for performance. Sound is a byproduct.
One of the top Alfa engine builders in the US has a set of modified IAP headers that he uses on motors on his engine dyno. He has shared data that shows how the HP peak varies with the length of tube from the collector to the open tail pipe. An engine can make upwards of 5 HP more tuning that length.
One of his customers paid Burns big bucks for a custom 4-1 system with an engineered collector and it made less power than his modified IAP headers. He was able to adjust some pipe lengths to get the Burns unit to equal his standard setup.
 

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For those of us on the sidelines listening in, this is amazing knowledge transfer. Many thanks and please keep it going!
 

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I have the Spruel Headers in my 1750.

https://www.alfabb.com/bb/forums/engine-repair-diagnostics-rebuilding/546233-s2-1750-rebuild.html

The engine has 10:1 overbore Spruel pistons for ~1870 displacement
Custom shorter guides, and new seals. Narrow valve stems (BMW I think). Ported and matched to the intake. Work done by Progressive in WA.
Rj cams: Intake: 429, Exhaust: 776 (11.3 lift)
40DCOE webers with 34mm venturi

135hp @ 7400 rpm according to one dyno.

The issue with these headers so far is clearance and heat. They are coated but still throw a lot of heat and are close to the brake booster and air can for my cross over intake (Euro 68 GTV 1750). I've considered wrapping them or coming up with some sort of heat shield. Still torn on how to go there.

They look very cool and the sound is good except for a distinct drone at 4K. (Talked with Paul and it is common if you run a single silencer) I have the stocks pipes with the rear silencer and a stinger so I may opt to redo the pipes in the same diameter as the header (2.5" I think) and run two Borla or Magnaflow silencers. My friend says it sounds like a Ferrari when you go through the range.
 

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engine exhaust

Boston Bertone, I run a similar setup in my 2Liter with 85mm applebites, RJ's cams, (same part numbers using105LC int and 108LC ex, and 3inch Magnaflows exhaust to the back, and yes, badass noise at rpm and fairly quiet in "normal" driving.
 

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The design of headers like Spruell's along with the similar Darstan headers sold by both Vintage Customs Alfa and Wes Ingram show a curved #3 primary in very close proximity to both the steering box and brake master cylinder. If you are running these headers it is a very good idea to fabricate a heat shield between the primaries and the other components. Looking at the original Alfa TI Super/GTA headers along with modern interpretations is a good indication that there is some disagreement over whether there is any advantage to be gained by designing such all-equal-length primaries.

As Ed's photo shows, there are lots of very stout engines running headers with designs similar to the original TI Super/GTA's. With this in mind I chose the full Alfaholics system for my hot-rod 2 liter build. In all my years of Alfa driving I've never had headers that didn't require at least a small amount mechanical persuasion in order to fit properly. Not so with the AH full stainless system. I was mentally preparing for a session of skinned knuckles and the obligatory blood sacrifice but to my great surprise the AH headers slipped right on with no trouble at all. Initially, the sound of the AH exhaust system was a little louder than a stock exhaust. It was a good sound although lacking in some of the drama that we closet "boy-racers" might like. Over time, however, the AH exhaust has opened up and now has a real Jekyll and Hyde character---relatively quiet around town but definitely prominent as the revs go up.
 
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I have the Spruel Headers in my 1750.

https://www.alfabb.com/bb/forums/engine-repair-diagnostics-rebuilding/546233-s2-1750-rebuild.html

The engine has 10:1 overbore Spruel pistons for ~1870 displacement
Custom shorter guides, and new seals. Narrow valve stems (BMW I think). Ported and matched to the intake. Work done by Progressive in WA.
Rj cams: Intake: 429, Exhaust: 776 (11.3 lift)
40DCOE webers with 34mm venturi

135hp @ 7400 rpm according to one dyno.

The issue with these headers so far is clearance and heat. They are coated but still throw a lot of heat and are close to the brake booster and air can for my cross over intake (Euro 68 GTV 1750). I've considered wrapping them or coming up with some sort of heat shield. Still torn on how to go there.

They look very cool and the sound is good except for a distinct drone at 4K. (Talked with Paul and it is common if you run a single silencer) I have the stocks pipes with the rear silencer and a stinger so I may opt to redo the pipes in the same diameter as the header (2.5" I think) and run two Borla or Magnaflow silencers. My friend says it sounds like a Ferrari when you go through the range.
peak power at 7400 is extremely high for a street motor. 135hp at reckon at the wheels?
 

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135hp @ 7400 rpm according to one dyno.
How did he measure RPM? The right way is from an ignition pickup. A less satisfactory method is where the operator "calibrates" from the roller rpm. If he overestimates it you get inflated HP (torque * rpm) and rpm. If he underestimates it you get low HP and a great torque curve at low rpm.
 

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Im in the same camp as others, the Spruell headers coated are the best bang fpr the buck performance wise.
Im able to get them in n out without drama on my race car, but they are tight n theres no room for hickups. Im dealing with vibration at full tilt that makes me think my motor mount needs replacement or shimming.

I also agree sound is factored more with intake n exhaust than the headers. I have quieted both my racers recently. The GTV got ss rear pipe added, the spider got a bolt in CA system. Both have webers with minimal filters n are rev happy, full on race engines. They still sound amazing.

For a street car, my gut tells me go w a stainless system n then go drive it.
 

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For a street car, my gut tells me go w a stainless system n then go drive it.
On our fall tour in November I had a couple (visiting profs from Italy, I think) following me because they liked the sound my hot-rod Super made with its c/r gears and stainless Alfaholics exhaust. That was fun and it does sound good when driven hard. Then my motor blew up: cracked head, blown head gasket, sundry failures, etc. We're doing a rebuild now . . .
 

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Discussion Starter #37
I’m currently running, stock headers, Original California cat, borla mid pipe and a stinger.

Would love a little more volume!

Are you guys sure a set of Alfaholics headers and maybe a new catalytic converter won’t put a grin on my face?

Unfortunately I have to run the Bosch fuel injection system so I don’t have Webber’s ..

Does anyone know if a cold air intake would make me happy sound wise? (Are they even available anywhere??)
 

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Woosh! VERY NICE!



*Partially* disagree on that blanket statement, kind sir. Primary lengths do alter the sound significantly, and so does overall header configuration (4 to 1, 4-2-1, etc...)

I bet a Spruell header (equal length 4-2-1) sounds different from a Sperry (equal length 4 to 1), which sounds different from a Shankle/Centerline/Vick's/Alfaholics (slightly unequal length 4 to 1.)
My comment was made because TS seems to have no interest in performance from headers. So I recaal a job I did for a GTV 2000 from a friend of mine. He wanted nicer deeper sound , no screamer. So we just made a mufflerless tailpipe in ED 60 , thick wall. Result nice deep sound, and on a trackday much nicer sound than many cars with headers.
total investment a few bob for the pipe, and some welding by myself.
So if sound is the thing, and performance does not matter why spend a lot on a header..
 

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Discussion Starter #39
My comment was made because TS seems to have no interest in performance from headers. So I recaal a job I did for a GTV 2000 from a friend of mine. He wanted nicer deeper sound , no screamer. So we just made a mufflerless tailpipe in ED 60 , thick wall. Result nice deep sound, and on a trackday much nicer sound than many cars with headers.

total investment a few bob for the pipe, and some welding by myself.

So if sound is the thing, and performance does not matter why spend a lot on a header..


ED60? What is that?

I already have a stinger pipe
 

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If stinger is yet again another muffler, try removing it. Doubt a cold air would make much dif noise wise for the better. Stock headers n ss Borja mid should be ok. Loosing the cat, would also wake it up. ?
 
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