you guys are the masters of all, so....
anyway, what we have here (other than a failure to communicate) is an edelbrock victor jr intake for a small block mopar. it has been converted to a port EFI intake by welding bungs in. it had previously been port matched (badly by a much younger me) and run as a carb manifold. so I grabbed some new gaskets, and re-gasket matched it further up the port. had to enlarge the ports in places quite a bit. roughed in with a die grinder and carbide bit, finished with a dremel burr, 80 grit sanding roll, 220 sanding roll, and 320 hand sanding. I haven't touched the plenum from what I did when I ported it many moons ago. I will be adding a 2 inch open spacer to make the 4bbl throttle body clear the fuel rails.
so, how do the ports look?
what should I do to the plenum, if anything?
[URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20151212_210758_zpslzftg57w.jpg.html][/URL]
[URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20151212_210750_zpsv98aml37.jpg.html][/URL]
[URL=http://s54.photobucket.com/user/dusterbd13/media/duster/20151212_210737_zpshzsiuwlk.jpg.html][/URL]
Dusterbd13 wrote:
so, how do the ports look?
what should I do to the plenum, if anything?
can't really see a lot... but what I can see... intake passage on right... could you radius the edge?
and similarly, could you radius the left passage??
I did shave them down by about 1/4 inch, but was afraid of making the walls of the port any thinner . also, I couldn't get much more than a few inches down. unless im misunderstanding what you're saying....
by radius, im assuming you mean to make the curve intruding into the port thinner, therby making that wall more of a straight shot vs gentle curve, right? if so, what will that get me?
Dusterbd13 wrote:
by radius, im assuming you mean to make the curve intruding into the port thinner, therby making that wall more of a straight shot vs gentle curve, right? if so, what will that get me?
??
I'm just talking about a gentle curve, what it gains you is flow around that corner.
I visualize the airflow... remember where the source of the flow is... the air is coming from the center, but it is being drawn, not pushed. A shallow radius there will allow easier passage to the valve
maybe add another photo.... slightly angled to show us the ports direction, and a better view of the area I pointed too??
I took about a dozen, and they are uploading now. Want a link to the album, or just post them here?
http://s54.photobucket.com/user/dusterbd13/library/duster?sort=3&page=1
try this. computer trouble....
Dusterbd13 wrote:
http://s54.photobucket.com/user/dusterbd13/library/duster?sort=3&page=1
try this. computer trouble....
argh... I hate photobucket... have to dump the modem after 4 or 5 clicks
I'm going to stop now... without actually holding the manifold to "see" (by sight, as well as touch) I could be giving you very incorrect information.... and that is the last thing I want to do.
In reply to Dusterbd13:
Looking at picture and trying to judge airflow is like trying to guess what color a car is by the song playing on it's radio..
Build, borrow, or buy, a flow bench.. It's cheap to build you need a shop vac. Plus some way to measure airflow.. I've used a variety of things starting with an old unisync.
If I build a flow bench, and make it flow less, I'm screwed and have to buy another part, correct?
chiodos
HalfDork
12/21/15 9:37 p.m.
Depends on the part and the mistake. I've seen people build welds up and even use jbweld to fill in areas. But if you just hogged out something way too much and now it flows like crap, then yeah maybe haha
ncjay
Dork
12/22/15 11:22 a.m.
http://www.hotrod.com/how-to/engine/1309-intake-manifold-investigation/
There is much to be gained by smoothing out the plenum area. Is there any reason you're working on the intake with injectors,etc. still attached? Maybe there won't be any negative effects, but I'd recommend stripping everything off the manifold while you're grinding on it. You're making lots of dust and chips and you don't need it creating problems down the road.
In reply to ncjay:
the injectors are junk, actually. I actually did no real work with them in, but was never real worried about them.
ive looked through that article a couple times, but not real sure what to implement on it.