What headers fit an RHS, or any other heads, raised exhaust port location?

Discussion in 'Technical' started by groberts101, Mar 19, 2015.

  1. groberts101

    groberts101 Member

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    Yep. Also seen that on other brands too with all these cookie cutter designs. The old blackjacks were all over the place too.. some guys would say they're great.. and others not so much.

    I just reread all this and have to say.. sorry to be so long winded here guys. When I'm not working hard enough.. I talk too much. lol

    Has anyone ever seen a custom up-swept header design for these cars? Not like the out of hood zoomie/demo-derby type stuff.. but maybe even something similarly built for a turbo/twin turbo setup? Not really interested in log style manifolds though.

    I have to wonder if I could package an up-swept style header and just bend down once it's all collected up and have only one main exhaust tube to deal with here. Could also end up with EL cutouts/dumps righ behind the front wheels too. Loud.. but cooler sounding. lol

    Probably need to go pretty far forward and down with the secondary(collector) though just to get long enough primaries on this thing. Don't like the fact that the weight will sit higher and more forward though.. but maybe someone else would buy them later on just for the novelty of the design. Would need to be heat wrapped for sure with such a design.. and stainless would probably become mandatory to help them live a long enough life if they were fully wrapped. But at least that way I can gain more clearance away from the shock towers and possibly allow the engine to sit deeper to help offset some of the added top heaviness. Would definitely draw extra attention when the hood was popped open.
     
  2. baddad457

    baddad457 Member

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    My old used Hedman 4 into 1 long tubes fit my Canfield heads just fine. Canfields had raised ports (by a half inch) I just got started digging into my 331 and unbolted the pass side header and it fell out the bottom of the car when unbolted. That'll give you an idea as to how well they fit the car. Ain't got to the driver's side yet but as I recall I had to jack up the motor to get that side in.
     
  3. groberts101

    groberts101 Member

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    Thanks for the reply. Safe to assume those are the same Hedman 88300's we were talking about above? Or did Hedman use to make another part number?

    How tight to the towers were the tubes at the nearest/tightest point?

    I'm usually the over-achiever "can't leave my $*#! alone" type once I start grinding away on my personal cylinder heads. I don't like leaving very much on the table while it's all apart but I'm having a bit of a conundrum over just leaving these ports exit size alone. IMO, and a few others I've talked to in the cylinder head business, agree that the openings are just too large for my smaller stock stroke cast bottom end motor in the streetable rpm ranges it'll live in.

    Now, obviously they'll still make power and the pocket and short turn is downright awesome for a budget head.. or just about any SBF head for that matter.. but I seriously think there could be some extra velocity and added blow-down length to be had by shrinking the exit just a bit more. I was going to do a D-port matched to a 1.625" primary to help avoid filling the floors.. but now am leaning towards a 1.5" squashed style port simply because they work so well for reducing short turn speeds and also help open up the roof to aid peak flow even with smaller diameter ports. Unfortunately that means more welding and lifting of the floor too.

    Plus.. just the 2 hours I spent on the I/E ports likely have the exhaust pushing more than 80% ratio of the intake side. IOW.. I don't really want to open up the intake side in a major way just to achieve some semblance of perfect balance between the I/E flow ratio. Was thinking I'd port match a squashed 1.5" tube right at the flange and go to the 1.625" shortly after and right at the bend. Mainly because I know the 1.5" would still flow sufficiently in a straight section.. but start to quickly fall short once the pipe turns away from the head.

    I'll try to get some pic's to give an idea of where I'm at now and maybe use a marker to show where I might go with it. Just to see what you guys think about the design.

    Thanks again.
     
  4. baddad457

    baddad457 Member

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    I've got my towers cut back (thank God I did that first off, sure came in handy unbolting the headers) The tubes almost touch the bottom portion of the towers that are left, but no rattles that I can tell when the car's in motion. Not sure of the part numbers, I'll look later today. These were bought used and are getting pretty thin, this is a perfect chance to install the newer set my son gave me off his Maverick. Found my coolant leak. After nearly 11 years, the rings are sealing perfectly. I pressurized the coolant system with the headers off and nothing came out. But when I hit the starter, coolant shot out of the #4 port. There's zero coolant in the oil, or at least none on the dipstick, so that's a good sign there's none getting past the rings. Gonna pull the heads and get em checked before going further. Hopefully they can be salvaged, if not then I'll just buy a new set of heads. Lookin at Brodix Street 5.0 or AFR 165's
     
  5. baddad457

    baddad457 Member

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    Finally found the numbers inside the head flanges,,,,,,88300 for a manual trans car ( has the tubes on the driver's side routed so's there's a nice size "hole" for the clutch linkage to fit through)
     
  6. groberts101

    groberts101 Member

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    Thanks for the follow up again. I posted in your thread too.

    If you were going to go with another casting though?.. AFR hands down over that 5.0 casting. You'll get better/lighter valve-train for your cash too. Dart Pro 1's are very nice castings too.

    Here's my little 165 cc heads so far. Once they're puttied and finished up.. maybe around 180 cc's or slightly less. Smaller 1.94" - 1.98" LS style flatter intake valves. 1.54" - 1.56" LS1 tuliped exhausts.

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]
     
  7. baddad457

    baddad457 Member

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    I checked the width of the Hedman ports (oval not square) and they're 1-1/8 as is. they can be massaged a bit and open them up to 1-1/4, that gonna cover those fat ports ?
     
  8. groberts101

    groberts101 Member

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    These ports are 1.3" x 1.3" as cast. Well.. more like 1.4" x 1.3" now that I angled the roof a bit more. When I have the time to spend after spring break vacation is all done.. I'll go get some more helium to start filling the floor about 3/4" inwards and about .250" - .300" thick. Then the 1.5" pipe will get squashed to match perfectly.

    The biggest problem I see with all these "intake CC" classed heads is that most all have the same exact exhaust port sizing(unless you pick the larger power-adder/N2O port, regardless of what the intake port flows. So, what would be perfectly sized for a 200cc head that sits on a medium to bigger sized motor.. ends up being on the larger size for my little 308.

    As of now.. the plan is to use the 1.5" pipe to better model the port down a tad, to keep the velocity nice and high, till it hits the turn.. then jump to the slightly bigger 1.625" piping to reduce pumping losses till I hit the collector. The 1.5" pipe fits inside the 1.625" pipe perfectly.
     
  9. baddad457

    baddad457 Member

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    Sounds like you're going with custom headers not the off the shelf stuff then.
     
  10. groberts101

    groberts101 Member

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    Sorta. I'm hoping to cut them off at the flange and meld the two designs together. I'd like to use the wider bolt spacings these heads have by making custom flanges.. and also raise the now slightly smaller tube up and away from the plugs to avoid so many issues others have had with these tight bays.

    But yeah.. I've pretty much decided to make whatever I have to just to get it all done. And if I can't sell em' later on?.. I'll just pass them down to my boys for their hotrods. Already told them... I'm going to be done with the Chevy and multi-brand stuff from this point onwards just to simplify my life and reduce inventory.

    Plus.. it's not like I make custom headers very often either.. and figure this would be a good practice run f0r when I get much more serious on the Kasse heads exhaust ports which will be full stainless using 321 flanges and stubs before chintzing out on the 304 stainless for the rest of the unit. Those things(Kasse exhaust ports) will need to have metal poured in becuase the floors need to be filled in all the way to the seat to get a nice long radii on the floors. If I could swap that Kasse exhaust port for the same shape and location of this raised RHS port?.. I'd do it in a heartbeat. Here's the Kasse P38 cutaway.

    [​IMG]

    Notice how quickly the short turn gets laid back compared to this little budget head. In his defense though.. Kasse left these exhaust ports in exact OEM locations.. reduced the angle to 10*.. and then just blew it out for flow big numbers. Even if I left them alone with milder port work.. they flow more than 240 cfm with a 1.6" valve. I just want a smaller and more efficient exhaust port while I'm melting aluminum to fill my intake ports floor. Plus, then I can use a smaller 1.54" exhaust valve and increase the intake size to 2.16" without fear for valve shrouding. I'll be over 12:1 SCR, so the little valves will still flow all that the other little big-bore motor will ever need.

    A little off-topic maybe but here's the intake as well. Mine will have even higher ports because I'm adding metal to the roof too. I'm sure that you still get the main idea here though. Look at all that metal he left for idjuts like me to grind away on! lol

    [​IMG]
     
  11. groberts101

    groberts101 Member

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    This will be the new exhaust port to mate up to the smaller 1.5" angled tube. Or close to it anyways. Probably square off the bottom just a tad more as the port hits the pipe(slight extra pipe stretching will be required to make the D shape) but it's close enough for a rough draft with no welding. Took me 3 times longer to edit these pictures and make playdoh to stuff the floor than it did to actually rough out the port. lol

    [​IMG]

    [​IMG]

    If this port can hit 210-220 cfm with this little 1.5" pipe and including the first 90* bend of 1.625" pipe on the flowbench?.. I'll be more than happy. Seems entirely doable as the throat/SSR/floor shape is really long and the roof has gone up a fair amount with an improved exit angle. I'm only guessing that by implementing this particular angled port and pipe combo.. I just screwed myself out of using my Hookers after all this hubbub is said and done. Stubs will be as long as possible..maybe around 1.5" inches out from port before I'm forced to kick the flow around corners to keep them off the shock towers. And now it'll be so specialized that I'll have to just hand all this stuff down to my boys when they start getting into some of this same madness themselves.
     
  12. baddad457

    baddad457 Member

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    You ever look at the exhaust ports on the 3.8 heads ? Sounds like those are what you're aiming for. I've never looked at flow numbers on those heads, but had a set I was keeping for awhile to do a hopped up 3.8 or 4.2 in my old 89 Ranger, just from their looks, they were far and away superior to the factory 302/5.0 heads, it's a shame they didn't cast em for the 5.0's. I took a bunch of pics of the newer Hedman's I just put in the car today to give you an idea of the clearances, I'll get em posted later on. Two of the tubes have very slight gaps between them and the shock tower and the steering box, that are paper thin. The rest have lots of room.
     
  13. rotorr22

    rotorr22 Member

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    They say a pic is worth a thousand words.

    Here is a pic of a brand new set of Hooker 6901's. No two ports are finished the same. I'm going to have to spend half a day grinding on these until they more closely match my AFR exhaust ports. Is it any wonder why people claim their tubes hit or get too close to steering and chassis components while others say they fit like a glove?
     

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  14. groberts101

    groberts101 Member

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    yep.. sorta like that. Even looks like the newer 3V mod motor stuff too. After a while of looking at all sorts of port designs.. it all blurs together and I don't know who copied who. lol

    And the gear box clearance I see on pics around here has me kinda worried a bit too. I think by the time I end up replacing and modding all those sections.. it'll look like Frankenstein and probably be better off just to keep tacking more pieces on till they finally hit the collector. Already planning on chopping and reducing my collectors down to 2 3/4" with homemade merges just to help the lower speeds and be better suited to improve scavenging on this littler motor. After all that.. I'd only have about 6" of original tubing left on each primary. :slap:

    Well now I'm thoroughly confused. Are all Hooker 6901's square like that on the bottoms?

    No numbers or stampings anywhere I can find.. so, maybe mine are Hedmans too?

    Mine are more oval shaped on each end and have no flats. Look to be pretty near the same otherwise.

    And yeah.. I seen lots of various headers through the years. Anyone who says that custom headers aren't worth the power.. must have gotten one of the "good sets".:90:
     
  15. baddad457

    baddad457 Member

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    Here's the pics I took today of the Hedman's installed
     

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