Alfa Romeo Forums banner

61 - 80 of 126 Posts

·
Registered
Joined
·
953 Posts
Nice! one of the many top drivers that got their career started in the SB series!
did you know that Hans Deen drove this car also? just once, when dady Huisman was angry on his son Patrick and he didnt let him race that weekend so Hans was there and raced this car, he told me that personally like he visits me every summer.
 

·
Premium Member
Joined
·
14,334 Posts
Is this the kind of sound that you are searching for?

This is Shankle headers into a 2 1/4" pipe with a single Borla Straight through muffler. It is not too obnoxious under light throttle.
Compression ratio and exhaust valve timing affect exhaust note.
 

·
Registered
Joined
·
1,855 Posts
Nah,.. I think he was thinking something like this, my bud Francois Sicard warming up the 512

 
  • Like
Reactions: alfaparticle

·
Registered
Joined
·
67 Posts
For street hot rodding the best “bang for the buck” will be the set that most resemble the original Shankle headers. They had extra long runners on the 2-1 sections as to be able to tune for optimum ( if you had ability and time). It seems Vick Auto and Centerline are closest. Yes there is a co-relation of sound to performance. However obtaining that optimum within legal / social parameters may not be possible. If you don’t want to invest more time and money experimenting, find a complete system that the headers of your choice fit. Invest your money in shocks -tires sway bars brakes. Winning drag race at the stoplight nationals is not as rewarding as beating your opponent around the corners- through the twisties...
 

·
Premium Member
Joined
·
735 Posts
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.
What primary tube size would be best for a strong street engine?
 

·
Registered
Joined
·
4,207 Posts
This is Shankle headers into a 2 1/4" pipe with a single Borla Straight through muffler. It is not too obnoxious under light throttle. Compression ratio and exhaust valve timing affect exhaust note.

Umm . . . Ed . . .? It's pretty obnoxious. >:) But, then, my Super's AH exhaust isn't all that far behind. We're all doing the best we can so this is just a burden we'll have to bear.
 

·
Registered
Joined
·
2,029 Posts
What primary tube size would be best for a strong street engine?
its all relative, it all depends on the intent of the motor you are building. first of all what type of header header config? in a nutshell 4-2-1 or tri-Y are better for street vehicles for low end torque but they do hamper high rpm running with the early merging of exhaust pulses. 4-1 are more race oriented for high rpm power and use.

old nords arent dynamos when it comes to revs unless its a purpose built 1300. i would reckon the 4-2-1 configs are better for the majority of builds on this board. pure non alfa race and crotch rockets motorcycles rev happy motors in search of top end power nearly always run 4-1
 

·
Premium Member
Joined
·
1,631 Posts
The original GTA headers are interesting to me as it appears the primary pipes are not of equal length, and to my eye the shorter primaries seem to have a smaller diameter. I will try and post a few pics over the weekend to illustrate.
 

·
Premium Member
Joined
·
14,334 Posts
In his for sale post Terry Stahley reports that his 210 HP/8000 rpm motor makes 4 more HP with Spruell headers compared with 4-2-1. The 230 HP chart that Richard Jemison posted was with GTA-like 4-2-1 headers which have quite long primaries and short secondaries.
 

·
Registered
Joined
·
4,207 Posts
GTA Headers imported from Italy back in the 70's. There is some debate as to whether or not equal length headers are better than those without.
 

Attachments

·
Registered
Joined
·
67 Posts
What primary tube size would be best for a strong street engine?
its all relative, it all depends on the intent of the motor you are building. first of all what type of header header config? in a nutshell 4-2-1 or tri-Y are better for street vehicles for low end torque but they do hamper high rpm running with the early merging of exhaust pulses. 4-1 are more race oriented for high rpm power and use.

old nords arent dynamos when it comes to revs unless its a purpose built 1300. i would reckon the 4-2-1 configs are better for the majority of builds on this board. pure non alfa race and crotch rockets motorcycles rev happy motors in search of top end power nearly always run 4-1
GTA Headers imported from Italy back in the 70's. There is some debate as to whether or not equal length headers are better than truly headers those without.
Tri-Y headers were popular for small block Ford V8s. Not sure how that would apply to 4 cylinders.
 

·
Premium Member
Joined
·
14,334 Posts
With 4-2-1 headers it is easy to make 2 & 3 the same length. #1 is usually an inch or two longer and #4 an inch or two shorter. " better" depends upon what you are trying to achieve. Equal length are probably best when you are looking for the highest peak HP.
 

·
Administrator
Joined
·
12,944 Posts
Personally, if the headers are not even why the heck were they made in the first place. It's just laziness, or cost cutting if not even.

If you were after compromise you would have left the original manifold on
Pete
 

·
Registered
Joined
·
1,145 Posts
did you know that Hans Deen drove this car also? just once, when dady Huisman was angry on his son Patrick and he didnt let him race that weekend so Hans was there and raced this car, he told me that personally like he visits me every summer.
Daddy Huisman was angry earlier, he did not allow Patrick to race, so Patrick rented e Squadra from Peter van Veen (one of the founders of the B series). at least, word is it happened like this how he got into the SB.
SB was a THE reason I started racing . Not only that, started a new series just because SB was allready way to expensive for me at that time (mid 90`s)..
 

·
Premium Member
Joined
·
1,631 Posts
Just an image showing the difference in primary diameters on GTA headers, 1st and 2nd pipes are larger then 3rd and fourth, go figure. Notice especially where 1 meets the 4th, as far as I know they all came this way..
 

Attachments

61 - 80 of 126 Posts
Top