2.8L, 3.4L DOHC Dyno time waster

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FieroWanaBe1
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Joined: Sun Mar 11, 2007 11:26 pm

2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

I've had a low mile 2.8L on the garage floor for over 15 years now.
I've been obsessed with knock off-weber carbes lately. I've aqciured a collection of Fake 48IDFs a couple fake 50DCOESPs, they need work but could be fun to play with.

I have an dea to help work with the younger engineers and machinists at my work (water brake MFG) and get them enganged in our products more. I want to put my crappy old 2.8L in the dyno cell we have for R&D.

I designed the Crank Adapter for the 1350/1410 flange 7 years ago, but the one I had made is lost, so Ill need to remake it.
I have a FWD metric/SBC adapter plate on order to mate to our bellhousing adapters.

I have a early citation Vaccum advance Distributor I found on ebay, to eliminate the ECU timing control. I want to attempt to prototype and 3d print a middle intake to bolt to the V6's lower intake a plenum and 3 IDF carbs.

I do want to get some dyno numbers on basic mods and what they are worth on the 2.8L, exhuast manifold porting, Y pipes, ETC.
I dont want to attempt to run the ECU, fixing my old harness and troubleshooting sounds like more work than I have time. Carbs may run like shit without any Jet or venturi tuning, but if I can pull air, I can get fuel.

I also have a 4150 to 2x DCOE manifold I could test if I can make a plenum for a holley 4 barrel, but the only Holley I have kaying around is a 250CFM 2 barrel.

I would like to do these tests on my LQ1 motor as well, since its sitting at a standstill. the plenum I made can get a new top to hold just about any carb, although I may need to shrink the plenum, but thats what dyno testing is about. What I dont have or know of is a simple ignition controller for the coil pack. I can use a microsquirt, I suppose, since everything is there on the engine sensor wise.
the 3.4 lets us play with cam timing to see how much we can affect the power curve.
car.
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Shaun41178(2)
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Re: 2.8L, 3.4L DOHC Dyno time waster

Post by Shaun41178(2) »

So msd and maybe Edelbrock makes an ignition controller for the ls1 engines when converted to carb. You might need a coil on plug setup, or a way to adapt to your vacuum dizzy. That might work.
FieroWanaBe1
Posts: 459
Joined: Sun Mar 11, 2007 11:26 pm

Re: 2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

The MSD coil near plug systems are pretty fixed, Even the Programmable ones, the hardware looks to be designed for the intended engine.
24x or 58X crank, 1x, 4x cam, 8 cylinders,
They offer a 4 cylinder midget kit that uses ford EDIS,
MegaJolt exists, using ford EDIS, Short of MSII I dont know of anything compatible with GM DIS, maybe the MSD 6AL2 programmable, since it does interface with HEI stuff.
car.
ericjon262
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Re: 2.8L, 3.4L DOHC Dyno time waster

Post by ericjon262 »

you could probably setup a microsquirt for ignition only no prob.
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FieroWanaBe1
Posts: 459
Joined: Sun Mar 11, 2007 11:26 pm

Re: 2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

I modeled this up at lunch.
Screenshot 2024-10-23 160407.png
Screenshot 2024-10-23 160407.png (498.61 KiB) Viewed 415 times
I need to verify I can stack IDF's that close together.
But this "should" bolt to a 60V6 Lower intake and 3 IDFs would sit on top.
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Shaun41178(2)
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Re: 2.8L, 3.4L DOHC Dyno time waster

Post by Shaun41178(2) »

V6 Chevy power manual has an idf setup similar to what you modeled there.
FieroWanaBe1
Posts: 459
Joined: Sun Mar 11, 2007 11:26 pm

Re: 2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

Screenshot 2024-10-24 130023.jpg
Screenshot 2024-10-24 130023.jpg (150.59 KiB) Viewed 392 times
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Shaun41178(2)
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Re: 2.8L, 3.4L DOHC Dyno time waster

Post by Shaun41178(2) »

Downdraft Webber's are a bitch to tune, but would essentially act like an ITB INTAKE.

I'd donate my iron head itb intake just for fun, but I just sold it.
FieroWanaBe1
Posts: 459
Joined: Sun Mar 11, 2007 11:26 pm

Re: 2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

I got in the HEI v6 distributer, it has a large body, so room might be tight with anything but a small carter 2 barrel.
I foud a new old stock small body distributer with vacuum advance on ebay.

Studying Chevy's build photo with IDFs, they have modified bodies to mount them closer together. The fuel filters cast into the bodies have been removed. Im not too keen on doing that. But without that modification, 3 carbs would totally hit the distributer.
So maybe, it would need to start as a a plenum bolted to the lower intake, and a couple hats for different patterns. Similar to the Edelbrock manifold.
I have a valueless 2 barrel carb from my SD4 as well as a lot of 48idfs.
car.
FieroWanaBe1
Posts: 459
Joined: Sun Mar 11, 2007 11:26 pm

Re: 2.8L, 3.4L DOHC Dyno time waster

Post by FieroWanaBe1 »

Falconer1_zpsbbpu41ak.jpg
Falconer1_zpsbbpu41ak.jpg (50.45 KiB) Viewed 139 times
DSC01906.jpg
DSC01906.jpg (139.67 KiB) Viewed 139 times
A few more snapsots from an S10 forum of the weber adapter once made.

Ill rework my design to be a plenum, more like this:
6f1ef4674ffa7545036d4fd343d61b41.jpg
6f1ef4674ffa7545036d4fd343d61b41.jpg (55.07 KiB) Viewed 139 times
A 48IDA is supposed to flow 330CFM per barrel, I assume at 28" H20 on a SF600, since I read that on the GT40s forum.
I still need to put my Chinese 48IDFs on the flow bench, but the Weber IDF flows less than the race oriented IDAs. But 330CFM @ 28" of water is equivelent to 281 CFM @ 1.5"HG, or 390CFM @ 3" Hg, so one 48IDF is probably close to what a 350CFM Holley 2 barrel can do. I also have one of those from My old SD4 combo, I might as well 3d print a top for that bad larry too.
car.
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