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Onepiece foactory manifold porting?

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Radio Flyer

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Joined
Mar 3, 2004
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16
(Wasn't sure where to put this...it's still one of "your" engines ;)).

Hey guys. Some of you may have seen my n00b status in modifying a 84 FWD Ciera wagon for sleeper duty. I'm pulling the intake manifold off for some porting and have some questions.
(Got that one damn Torx-45 bolt on the front R side....dammit...time to go to Sears again.)


(Parts list (8445 heads, 2552 block, factory PFI intake))

My biggest puzzle at the moment is what I can do to a one piece intake manifold. All of your turbo GN stuff points to a 2 piece design, with upper and lower halves. Any input on modifying a "one piece/red-dot" factory manifold?

--So far, it looks like the factory manifold is about a 1/4 inch smaller than the TB's opening. Time to change that with the trusty Dremel :).

--It looks like, FWIR here, the stock intake ports are pretty restrictive. I've seen pix of the ports over on gnttype.org. But, nothing on the 1-piece intake manifold. I know enough to stay to the top and sides of the port for more flow. I'm more on a quest of exploration at the moment, taking good notes, then the intake porting will begin. The block only has 60k original miles on it.

How are the port sizes in relation to one another? Pretty even? Any weird kinks/bumps to look for? How thin/thick are the port walls?

That's all for now. Please let 'em fly, ladies and gentlemen. Time to screw some imports :). Stripping the car down to 2,000lbs-ish and staying n/a for a while is my goal. It'll be boosted later on, probably with factory S/C parts.
 
You might try lurking over in the hot air forum. The hot airs use a one peice intake simular to yours. Look for threads that mention new hot air intakes.
 
(Warning, tech-head rant. :p)

I'm on the trail of this engine having come out of an 85 Regal Type S (150hp, 220ft/lb stock (?).) That's definitely helpful rather than chasing down parts numbers and pictures. (No offense guys, but clues are a good thing ;)). The intake points to what would be the back of the block. I'll post pictures of it this weekend and see what anyone has to say. I've already found the TB opening to be a 1/4 inch smaller than the TB itself. The TB I'll definitely polish while I'm at it.

(---Porting tips???)

It looks like there's "humps" before the ports. They sit inside the plenum right up next to the runners at the bottom of the ports.
I'll get pics when it's clean. My best guess is that they are there to improve velocity, and force more air to the middle and top of the runner. It'll be interesting to look at the disparity in port sizes from the intake to the head. I know to stick mostly to the top of the ports, and only remove what I think I have to. Don't touch the bottom, and try not to widen it too much.

Looking at a cross section of the 8445 heads, it looks almost like a venturi (sorta). Where it gets a bit taller and then necks down before the valve. What you guys post here is that the intake's runners are much much smaller than the cylinder heads, and there's plenty of room. I just gotta take it off and look....so far I see some potential though. I'm glad to see so many of you getting good results from the factory parts.

L8r...time for a buzz and more reading :).
 
correction...no such thing as a "type S". Talked to the previous owner and it seems to have been a frankenstein engine by a buddy of his. I was a fraid of that....but it's got the right mix of parts to make it run well. Still no luck on finding a similar intake.
 
Picture as promised. They aren't meant to be beautiful until I'm done with them. What I pulled of was a slight surprise, and should yield decent butt-dyno gains.


Here's the intake after she's been cleaned up a bit. Any takers on what it came off of? The thermostat gasket I found by looking under RWD Regal...weird... the intake part number is 25524316.

intake.jpg


Here's where it got really interesting. What I'm searching for are restrictions that make a big difference in flow. Reading what some of you have here, plus a few details in the port, wind me around to a particular conclusion. This intake is fresh off the block after about 60k miles of service. Desposits collect in crevices, and along the walls and what not. The black marks you see here, surrounding the port, exactly match a pattern of ugly carbon colored crud in the cylinder head. This reduction in size on the intake's part, make's a significant restriction in the total port flow. The beauty of it is, it's just there that the casting necks down right at the manifold opening. The entire port doesn't do that. Around the injector boss' opening and in the lower part of the manifold, there is some ugly flash, splatter, and ridges that can be taken care of. I'm glad it's mostly within easy reach. polishing deeper in there should be easier with a flex shaft dremel. The port is narrower near the plenum and much smoother. This'll mostly be a polish job. Some may complain of fuel puddling, but this is a dry manifold with the injectors at the bottom.

ports.jpg


The TB will be hand ported. It smoothes out pretty easily being aluminum. (I know there's a bolt missing out of it...The one in there is just a bit more stubborn) One thing I'm looking at is the IAC area. It can me smoothed internall rather easily and has it's ugly little humps, too. I'm wondering it could improve throttle response to smooth that area. At the very least it can't hurt. I'll post pix when done. The engine bay deserves a before and after shot ;).




tb.jpg
 
a few more just to prove I'm not kidding!

Look at my engine picture a bit closer. They match the lc2's side bolt valve covers. The engine says GM 3.8 on the side of the block and up near the top rear left cylinder head. The HEI(EST) is what never made sense, going with the 20 bolt pan, which gnttype.org says didn't come until 1985 and later. This car is an 84. But, the HEI and what not looks like the old unit that came on the car.

[IMG=http://pages.prodigy.net/burnirubber/pictures/gutted.jpg]the car[/IMG]

the head
[IMG=http://pages.prodigy.net/burnirubber/pictures/head.jpg]the heads[/IMG]

[IMG=http://pages.prodigy.net/burnirubber/pictures/gutted2.jpg]a sideways turbo reagal block?
[/IMG]

After looking up the vin and comparing it to a Chilton manual, it's a 3.8 that originally came in it from the factory. But the hard stuff looks like turbo regal parts except for the ignition, intake, exhaust, and HEI...all bolt on parts from the previous engine are there. The casting numbers and looks of the hard stuff (block, heads.) resemble your turbo engines. The accessories, to me, appear to be the only difference. That's my whole point of posting, doinking with the car, and trying to get more power out of it.

Does it or does it not have the same parts as some turbo regals/GN's? The physical long block resembles one, but the rest doesn't.
 
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