351C Multiport EFI conversion help needed

For anything machine shop / speed shop or engine specific. More technical than the range but not quite tuning specific.
AcesArneson
Posts: 38
Joined: 2022 Apr 19, 07:23
Location: Fort McMurray, Alberta, Canada
Vehicle Information: 1973 Mustang Convertible
351 Cleveland 2V conversion to EFI (Ford EEC-V) dyno’d at 441hp @6000 rpm on a 750 CFM shop carb. Edelbrock 61629 heads 10.66:1 compression
-Donor car for EFI wiring harness is a 2003 Lincoln Town Car 4.6L CoP
Intake for EFI is a Weiand 7516 with bungs welded into runners.
FMX transmission swapped out to rebuilt 4R70W from a 2003 Mustang with J mod

351C Multiport EFI conversion help needed

Unread post by AcesArneson »

Wonder if you can chime in on the planning stages of a rebuild I am doing for a 450 hp 351 Cleveland. Having a terrible time finding parts right now due to after effects from Covid. Going for the old school look on EFI port injection so trying to locate reasonably priced parts is tough.

*Does anyone know of any vehicles that came with a very short MAF (like 1-2" high) that I could fit inside the air cleaner on top of a 4 barrel throttle body. It will need to be 85mm at least.

*Also wonder if anyone has a source on reasonably priced 800-1000 cfm 4 barrel throttle bodies. I see a couple of knock offs in the $300 range but I wonder how reliable they are, if you have used one with success please give me the brand name and a supplier if possible. Most are in the $600 range.

*Intake manifolds for 351C's are extremely rare right now, does anyone have a source for new manifolds that are either EFI ready or can have bungs added? I would really love to try the CHI heads and intake but I can't find any. I am thinking 3V-185's. My mechanic is an Edelbrock dealer and they are pretty much out of stock on every suitable manifold option so I am all ears.

Thanks!
decipha
Posts: 4956
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: 351C Multiport EFI conversion help needed

Unread post by decipha »

you can use the gm maf like the mass flo kits, be sure to toss screens on both sides

no idea on the rest, clevelands are a dying breed not too many go EFI
red5.0fogger
Posts: 148
Joined: 2021 Mar 22, 15:58
Location: Newington CT
Vehicle Information: 1986 Mustang GT, Stock block, TFS 170 Heads , N41 cam, ported cobra intake, nitrous, T5 , 3.73s

Re: 351C Multiport EFI conversion help needed

Unread post by red5.0fogger »

I had a truck with a 302 and headers with a an Edelbrock 600 carb. In my opinion switching to EFI wouldn't be worth the hassle.
once they're tuned a carb and efi engine all else being equal will run the same. Sometimes the carb'd will make more power due to charge cooling. Now if you had a small cam and went to a big cam the idle will be screwy on the carb'd model but it can be tuned out with some effort.
red5.0fogger
Posts: 148
Joined: 2021 Mar 22, 15:58
Location: Newington CT
Vehicle Information: 1986 Mustang GT, Stock block, TFS 170 Heads , N41 cam, ported cobra intake, nitrous, T5 , 3.73s

Re: 351C Multiport EFI conversion help needed

Unread post by red5.0fogger »

ps I am speaking of an NA combo, boost would really require efi
AcesArneson
Posts: 38
Joined: 2022 Apr 19, 07:23
Location: Fort McMurray, Alberta, Canada
Vehicle Information: 1973 Mustang Convertible
351 Cleveland 2V conversion to EFI (Ford EEC-V) dyno’d at 441hp @6000 rpm on a 750 CFM shop carb. Edelbrock 61629 heads 10.66:1 compression
-Donor car for EFI wiring harness is a 2003 Lincoln Town Car 4.6L CoP
Intake for EFI is a Weiand 7516 with bungs welded into runners.
FMX transmission swapped out to rebuilt 4R70W from a 2003 Mustang with J mod

Re: 351C Multiport EFI conversion help needed

Unread post by AcesArneson »

Definitely going EFI, not for horsepower but future upgradability to boost, plus I suck at tuning carbs, haven't had one since I sold the 77 MustangII.

Does anyone have the item number for the MAF from the MassFlo Kit? They want too much for their MAF.
red5.0fogger
Posts: 148
Joined: 2021 Mar 22, 15:58
Location: Newington CT
Vehicle Information: 1986 Mustang GT, Stock block, TFS 170 Heads , N41 cam, ported cobra intake, nitrous, T5 , 3.73s

Re: 351C Multiport EFI conversion help needed

Unread post by red5.0fogger »

since the injectors will be showing, plus a fuel rail, is it worth hiding the mass air meter?
AcesArneson
Posts: 38
Joined: 2022 Apr 19, 07:23
Location: Fort McMurray, Alberta, Canada
Vehicle Information: 1973 Mustang Convertible
351 Cleveland 2V conversion to EFI (Ford EEC-V) dyno’d at 441hp @6000 rpm on a 750 CFM shop carb. Edelbrock 61629 heads 10.66:1 compression
-Donor car for EFI wiring harness is a 2003 Lincoln Town Car 4.6L CoP
Intake for EFI is a Weiand 7516 with bungs welded into runners.
FMX transmission swapped out to rebuilt 4R70W from a 2003 Mustang with J mod

Re: 351C Multiport EFI conversion help needed

Unread post by AcesArneson »

Found the part# for the MAF on another forum. If anyone else is looking for this in the future the GM part# is 25168491
AcesArneson
Posts: 38
Joined: 2022 Apr 19, 07:23
Location: Fort McMurray, Alberta, Canada
Vehicle Information: 1973 Mustang Convertible
351 Cleveland 2V conversion to EFI (Ford EEC-V) dyno’d at 441hp @6000 rpm on a 750 CFM shop carb. Edelbrock 61629 heads 10.66:1 compression
-Donor car for EFI wiring harness is a 2003 Lincoln Town Car 4.6L CoP
Intake for EFI is a Weiand 7516 with bungs welded into runners.
FMX transmission swapped out to rebuilt 4R70W from a 2003 Mustang with J mod

Re: 351C Multiport EFI conversion help needed

Unread post by AcesArneson »

red5.0fogger I believe so! In all honesty I would scrap the retro look if I could find a GT40 intake for a 351C but I have had no luck.
AcesArneson
Posts: 38
Joined: 2022 Apr 19, 07:23
Location: Fort McMurray, Alberta, Canada
Vehicle Information: 1973 Mustang Convertible
351 Cleveland 2V conversion to EFI (Ford EEC-V) dyno’d at 441hp @6000 rpm on a 750 CFM shop carb. Edelbrock 61629 heads 10.66:1 compression
-Donor car for EFI wiring harness is a 2003 Lincoln Town Car 4.6L CoP
Intake for EFI is a Weiand 7516 with bungs welded into runners.
FMX transmission swapped out to rebuilt 4R70W from a 2003 Mustang with J mod

Re: 351C Multiport EFI conversion help needed

Unread post by AcesArneson »

decipha wrote: 2022 May 05, 20:21 you can use the gm maf like the mass flo kits, be sure to toss screens on both sides

no idea on the rest, clevelands are a dying breed not too many go EFI

Re: MAF mounted inside old-school air cleaner, right on top of carburator style throttle body.
In the write-up you mention that it is preferable to use slot style MAFs. Would there be a problem with airflow using a Ford MAF? As long as I put screens on both ends, as you suggest, will I be able to tune it ok or do the slot style MAFs need perfectly straight airflow to work.
If I did us a GM MAF, how would I adapt the GM signal to something the Ford EEC-V could use?
canuck1
Posts: 67
Joined: 2021 Mar 31, 17:29
Location: Victoria, BC CANADA
Vehicle Information: QH, TunerPro RT 5, GUFX_220418.xdf, A9L2_220405, DECIPHA_220505.ADX, 395w, AFR 195CC Renegade heads, Comp XE274HR cam, Siemens-Deka V 80lb/hr (shorties), Mass-Flo-EFI style 4bbl throttle body with GM maf on top. Custom long tube headers, sidepipes, 5 spd manual.

Re: 351C Multiport EFI conversion help needed

Unread post by canuck1 »

Here's what my 351w based motor looks like:
cobra air cleaner 2020 (reduced).jpg
inside air cleaner 2020 (reduced).jpg
Mine's not actually one of the now defunct Mass-Flo-Efi systems but originally an Edelbrock Pro-Flo II system, converted to mass air with the modified GM MAF and the secret ingredient (frequency to voltage converter) to make the signal Ford EFI compatible.

I have a soft spot for Clevelands, having built a few for stock car racing in the eighties, but their advantages then have been overcome by technology and availability of Windsor style components. I just don't think they are worth the extra cost, time and fitment issues. If you want to, go for it!

Sean
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