vortec multi-port

Performance modifications, tips & tricks

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superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

vortec multi-port

Post by superglock »

Has anyone played with the mercruiser 860373-c intake set-up from a 350 mag mpi Alpha/Bravo mercruiser engine. It has a throttle body on it with a adaptor underneth it, The manifold looks to take a square bore gasket. I have a hevy 383 with Eagle crank and rods, Speed-pro hypertech pistions, reground the cam to match a roller comp 4x4260 cam, the heads are vortec with upgraded springs and screw in studs and guide plates, Put in a set of 1.52 roller tip rockers with hardened pushrods, The intake is a Performer rpm. I am trying to decide on efi and saw the multi-prot upgade pages, I am putting this into a jeep and not starting with the chevy chassis. I have looked at the FAST stuff and the powerjection, I was looking around and found this forum and did the reading on the conversion some of you have done and then ran across this other style of manifold and was wouldering if anyone had some knowledge.
It says its off a vortec and it is direct multi-port, I did some checking and it looks like a square bore throttle body would go on it for air control, Tps and iac. I have found a TBIâ„¢ from Auto-nomics and then run it with a Megasquirt computer setup.
Anyone have any input?

Thanks

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

I did a Google search of the number you posted. I haven't seen that intake before. It looks like a pretty neat setup. I wouldn't hesitate on using one of those.

Jeff

Bowtiewarrior
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Joined: Thu Mar 15, 2007 12:02 pm
Location: flying past ford trucks...

Post by Bowtiewarrior »

http://www.ebay.com/itm/MERCRUISER-6-2- ... 500wt_1186

The intake Looks great, I think it would be a good choice there are plenty of ways to adapt a throttle body to a square bore now.

CrazyHoe
Posts: 6228
Joined: Tue Feb 19, 2008 8:30 am
Location: Mtl; '98 2dr4x4 Tahoe, L31,Hookers Long T, 0411,EFIlive, 4L80-E,dual 3",marine int+inj

Post by CrazyHoe »

Last edited by CrazyHoe on Fri Feb 10, 2012 6:54 am, edited 1 time in total.

Chevy 97
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Joined: Tue Jan 24, 2012 1:19 pm
Location: 97 ECSB K1500 6.3L 4L80E 14 bolt SF Hydro Boost, Headman Ellite Headers, 140 amp alt.

Post by Chevy 97 »

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Last edited by Chevy 97 on Fri Feb 10, 2012 7:12 am, edited 6 times in total.

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

As far as a throttle body goes---Why not use a 1/4" thick aluminum plate and make an adapter to use the stock Vortec T/B????

Jeff

Chevy 97
Posts: 1077
Joined: Tue Jan 24, 2012 1:19 pm
Location: 97 ECSB K1500 6.3L 4L80E 14 bolt SF Hydro Boost, Headman Ellite Headers, 140 amp alt.

Post by Chevy 97 »

I measured that up already. Our TB barely fits inbetween Studs, and is a Little longer. It still looked do able.

CrazyHoe
Posts: 6228
Joined: Tue Feb 19, 2008 8:30 am
Location: Mtl; '98 2dr4x4 Tahoe, L31,Hookers Long T, 0411,EFIlive, 4L80-E,dual 3",marine int+inj

Post by CrazyHoe »

I would use the E-Brock elbow on that one

Bowtiewarrior
Posts: 417
Joined: Thu Mar 15, 2007 12:02 pm
Location: flying past ford trucks...

Post by Bowtiewarrior »

Image

I already did this, it works well. Actually I think i'm going to be selling my adapter plate to buy a 90 degree elbow to use a 80-90mm LS1 style t-body. If there is one thing this forum will prove, Anything can be done just do it!

Chevy 97
Posts: 1077
Joined: Tue Jan 24, 2012 1:19 pm
Location: 97 ECSB K1500 6.3L 4L80E 14 bolt SF Hydro Boost, Headman Ellite Headers, 140 amp alt.

Post by Chevy 97 »

Image

This is the elbow I was talking about.

Chevy 97
Posts: 1077
Joined: Tue Jan 24, 2012 1:19 pm
Location: 97 ECSB K1500 6.3L 4L80E 14 bolt SF Hydro Boost, Headman Ellite Headers, 140 amp alt.

Post by Chevy 97 »

Bowtiewarrier: That is what I am going to use when I go to the Big Block in the future. Nice job. Did you machine that yourself?

Bowtiewarrior
Posts: 417
Joined: Thu Mar 15, 2007 12:02 pm
Location: flying past ford trucks...

Post by Bowtiewarrior »

Chevy 97 wrote:Bowtiewarrier: That is what I am going to use when I go to the Big Block in the future. Nice job. Did you machine that yourself?
I was in the shop when it happened, it was done on a CNC machine so really after all the measurements were made, it was data entry and click. then jaw drop and drool..

it works great, I just want to go similar to that 90 altho I need to look around I want it to have a little more of a radius to it than that Edelbrock one.

superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

Post by superglock »

Thanks for the pictures, I am not the best with a computer. The checking I did yesterday, It looks like the stud pattern is the same bolt pattern as a square bore Holley or Edelbrock carb. The after market throttle bodys like the FAST and Autonomics use the same square bore bolt pattern. The Mercruiser uses a adaptor on the intake to mate it to the throttle body and the throttle body is a 90mm unit, I dont know what the stock Chevy is. The Fast or Autonomics unit could be used for the air control, tps sensor and Iac unit. The manifold has the air temp screwed in behind the TBIâ„¢ unit where the brake vacum port is, I could more it or tap another hole for the brakes. This sensor location for the air temp is better I think because it will give a truer temp for the air going into the engine.
I was hoping some one has had on in there hands to look at the TBIâ„¢ stud pattern and just a general look.

Thanks for the input and keep it coming.

superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

Post by superglock »

Well I made a offer on the intake set-up. We will see what happens. I found all the injector info such as dimentions and flow, The stock ones are 44lbs. I was told I needed 4-60lb injectors if I was going to run a 4 injuctor set-up, This should meen I would have plenty of injector with the stock ones.

superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

Post by superglock »

A little late update, I bought the manifold, A Fast throttle body and some rails. Now I need to decide on injectors.

Image
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Sleepy-S10
Posts: 151
Joined: Sun Oct 29, 2006 7:15 am
Location: Central NH

Post by Sleepy-S10 »

Looks good. I couldn't swing the aftermarket TB when I put mine together. I traded off the Marelli Pico injectors that were really too big anyway and ended up using stock GM injectors but I can't remember the application right now. Did you have to buy new rails? I was able to make spacers and raise mine to work with the GM injectors which was nice. The air sensor issue is a trade off. If the sensor is screwed into the intake it can be slower to respond with the manifold itself heating or cooling the sensor. In the air stream you'll get actual air temp changes but you won't measure heating from the manifold as the air moves through. Either way if you're doing tuning most of this will get worked out as you dial the engine in.

superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

Post by superglock »

Image
Image


Well it is finailly together , On a engine and in the jeep all hooked up. The wiring is done and it runs, Still needs more computer tuning.[/url]

Used ford injectors, ebay fuel rails and Fast throttle body and fuel pump.

Hog
Posts: 5025
Joined: Tue Dec 11, 2001 4:00 pm
Location: 1997 Chev ECSB L31 350 1997 GMC Sierra SLE RCSB, Ontario

Post by Hog »

Looks good, the crossram L31 appearing intake required tuning to remove a cold lean bog upon throttle application, and its pretty close to the stock unit.

I can see this intake requiring even more recalibration, but nothing that cant be overcome.

How are you supplying a CMP sensor signal with that distributer?

peace
Hog

superglock
Posts: 14
Joined: Wed Feb 08, 2012 3:21 pm
Location: Selah

Post by superglock »

This is in a jeep and using a microsquirt computer system, The microsquirt is a baby brother of the megasquirt. A custom tunable systemthat you can put on most anything. Took it in for some tuning work tonight and it sounds really good, Now I just need to get it out and drive it.

Hog
Posts: 5025
Joined: Tue Dec 11, 2001 4:00 pm
Location: 1997 Chev ECSB L31 350 1997 GMC Sierra SLE RCSB, Ontario

Post by Hog »

superglock wrote:This is in a jeep and using a microsquirt computer system, The microsquirt is a baby brother of the megasquirt. A custom tunable systemthat you can put on most anything. Took it in for some tuning work tonight and it sounds really good, Now I just need to get it out and drive it.
Oh OK, so you arent running sequential injection? Batch fire. Thats makes it much easier for install.

peace
Hog

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