Dawg’s performance intake
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Topic: Dawg’s performance intake
Posted By: Dawg
Subject: Dawg’s performance intake
Date Posted: 08 April 2010 at 11:15pm
Here's the throttle body I bored out for Luke's new intake system. It was opened up to 56mm. This is fresh off the machine.  A new throttle plate and general clean up and it's ready for final assembly. Next will be modifications to an upper plenum to open things up. This should help with high RPM power. DG ------------- You dream it up....I'll make it |
Replies:
Posted By: Dawg
Date Posted: 09 April 2010 at 10:21pm
Here's the completed big bore throttle body.   It ends up it was a good thing I machined the bore very precisely. The relationship between the bore and the throttle plate (butterfly valve) is critical. A little off and you either bind or the plate jams in the closed position. Got it dialed in now....:) Here's a look at how much bigger the bore is now. Quite a difference.  This thing should kick ass! DG ------------- You dream it up....I'll make it |
Posted By: Capt Fiero
Date Posted: 10 April 2010 at 12:08pm
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Oh ME ME ME ME, and EVERYONE else in the club. We need to know how much? Do you want me to start setting spare TB's aside for you to do boring out and then exchange on them? ------------- Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd. |
Posted By: Bassman
Date Posted: 10 April 2010 at 3:28pm
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lol...Ya Baby:) ------------- Brian (Bassman) 86 GT Fastback 3.2L 2013 Mazda3 Sport GS SkyActive [IMG]http://i170.photobucket.com/albums/u243/Bassman68/BassmanSignature.png"> |
Posted By: Dawg
Date Posted: 10 April 2010 at 3:50pm
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I'm charging $150 exchange for the TB and $300 exchange for the plenum. I still owe you for parts so talk to me at the meeting. But yes, if you can gather up a bunch of TB's to do at once it would be cheaper. I can't see going down in price on the plenum however, it's going to involve a lot of cutting and fitting. We'll see once I actually do one. I'm bringing the big bore TB to the meeting so people can see it up close. DG
------------- You dream it up....I'll make it |
Capt Fiero wrote:Posted By: Capt Fiero
Date Posted: 11 April 2010 at 1:19am
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Just a side note, these will a minor (not the major port job) just the opening up of the intake to match the tb size, will gain an average of 5-7hp, just find the old Darrell Morris website. ------------- Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd. |
Posted By: Dr.Fiero
Date Posted: 11 April 2010 at 7:03am
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And a recap on my quickie math.... 52mm-56mm should equate to a 300cfm to a 348cfm change. |
Posted By: Dawg
Date Posted: 21 April 2010 at 12:04am
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With the big bore TB done, I'm starting on the upper intake. When you cut one of these open it's easy to see the restriction in the neck. In my opinion, there's not much point installing a big bore TB without modifying the intake also. I'm sure there is a benefit either way, but it's easy to see the massive potential of an opened up intake. At the very least, the opening right behind the TB would need to be ported to match the new 56mm bore.    As you can see, lots of cutting and fitting before you can weld anything. I'm not going to replace the EGR port. DG ------------- You dream it up....I'll make it |
Posted By: Capt Fiero
Date Posted: 21 April 2010 at 4:48am
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Looking good, you are going to want a test mule car to test fit the intake on, there is no a lot of room under that area of the intake before it smacks into the valve cover and or dist shaft. It looks like this mod will only work for EGR delete cars as well. Regardless it will be interesting to see it on a car that is reved up on regular driving to see just how much of an improvement it makes. I might have to reconsider your offer on the intake, if it appears stock when looking at the intake installed, I'll bet I could pass collectors status with it installed. ------------- Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd. |
Posted By: Dawg
Date Posted: 21 April 2010 at 11:03pm
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Oh I'm sure no one but a Fiero expert would notice the extra bulge under the neck. It would be nice to find the original red color in a handy spray can. Anyone ever try to find one? Get me another TB and you can have this one. Luke doesn't seem to be in a hurry so he can have the next one. I should have this plenum done by Sunday. DG
------------- You dream it up....I'll make it |
Posted By: Dawg
Date Posted: 23 April 2010 at 2:00pm
OK....here's the welded assembly. It went together well. Lots of hand fitting as I suspected. Makes quite a difference when you look down the tube. It's cavernous!  I still need to port the opening and figure out where to mount the small spigot. I forget what it's for again. Its stock position is pointing straight down and it's maybe 1/4" in diameter. Anyone know? I'm going to fit it onto a lower plenum I have here to see if there is any clearance issues. I doubt it. DG ------------- You dream it up....I'll make it |
Posted By: Dr.Fiero
Date Posted: 23 April 2010 at 2:05pm
The vaccum port? That went over to the PCV valve. |
Posted By: Dawg
Date Posted: 23 April 2010 at 2:37pm
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PCV Valve.....that makes sense. I'm going to see if it's better to shift it over a bit. Pointing straight down won't work anymore. Thanks, Damien ------------- You dream it up....I'll make it |
Posted By: Dawg
Date Posted: 25 April 2010 at 9:18pm
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Today I delivered Dave's big bore intake. We compared various intakes he had and then had a look at his 88 engine and decided that the PCV valve's spigot could be mounted just about where the stock one is. There was nothing in the way after all. I have no pics but I think Dave has some. Maybe a pic of it installed soon? DG ------------- You dream it up....I'll make it |
Posted By: Car-2-Lo
Date Posted: 25 April 2010 at 9:34pm
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Today's pics at Dave's 
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Posted By: Capt Fiero
Date Posted: 25 April 2010 at 9:36pm
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The intake does look amazing, but I was not the one taking the pics of it, Car-2-Lo was. I would have installed it today, but I need to make an EGR block off of some sort. Also I think you still have the bigger Throttle body or did Luke by that from you? To the untrained eye, Dawg's new intake looks stock and in even better than new condition due to the paint he used. This is truly a work of art, (as are most parts from the Dawg) I'll try to get it installed in the next week. I'll also have to find my aftermarket EGR delete chip and swap that in at the same time. ------------- Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd. |
Posted By: Dawg
Date Posted: 25 April 2010 at 10:33pm
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Nope I still have the throttle body. I'll make him another one when he's ready. I still need to make a template using the new throttle plate as a guide. Let me know when you will do the swap over and I'll make sure it's ready. DG ------------- You dream it up....I'll make it |
Posted By: bill
Date Posted: 26 April 2010 at 6:24am
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I agree that there isn't a lot of joy in putting larger TBs on Fieros. When you suck and see on a flow bench and you do it as an assembly, the TB doesn't show much because the bottleneck is in that manifold neck. Attacking that is the way to go and I rather like the approach you used. Would love to see before flow measurements and then with just the neck mod, and then the TB enlarged as well. 56 mm is probably all the 2.8 can use. I run a 62 mm on a 3.4 (not in the Fiero) but with a totally different plenum without the restrictions.
------------- 1988 3.2 turbo Fiero 1957 3.4 in Jamaican MG 2009 2.0 Pontiac GXP coupe |