Alternative Port EFI Intakes This board is for tech discussions and questions about aftermarket port EFI such as the HSR, MR, SR, BBK, FIRST, etc.

Edelbrock 3502 Multiport intake. Any thoughts?

Thread Tools
 
Search this Thread
 
Old May 17, 2022 | 08:02 AM
  #1  
robertfrank's Avatar
Thread Starter
Supreme Member
20 Year Member
Liked
iTrader: (27)
 
Joined: Apr 2004
Posts: 3,001
Likes: 62
From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Edelbrock 3502 Multiport intake. Any thoughts?

Hey guys, I have the opportunity to pick up an edelbrock 3502 tbi to multiport intake locally for dirt cheap. Has anyone here ran this intake? I know it's basically a single plane intake you can bolt a tbi unit to. Any input would be great

Reply
Old May 17, 2022 | 10:28 AM
  #2  
Tuned Performance's Avatar
Sponsor
20 Year Member
Community Builder
Community Influencer
Community Favorite
iTrader: (95)
 
Joined: Dec 2004
Posts: 16,930
Likes: 1,017
From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Just curious would you run with picos or block the injectors bungs and go tbi ?
Reply
Old May 17, 2022 | 10:42 AM
  #3  
robertfrank's Avatar
Thread Starter
Supreme Member
20 Year Member
Liked
iTrader: (27)
 
Joined: Apr 2004
Posts: 3,001
Likes: 62
From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Originally Posted by Tuned Performance
Just curious would you run with picos or block the injectors bungs and go tbi ?
no I would do a multiport conversion. Run some 24lb injectors and an adjustable regulator. I already have an ebl flash with a port mod coming.
Reply
Old May 17, 2022 | 10:52 AM
  #4  
Tuned Performance's Avatar
Sponsor
20 Year Member
Community Builder
Community Influencer
Community Favorite
iTrader: (95)
 
Joined: Dec 2004
Posts: 16,930
Likes: 1,017
From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Would be great for torque, with a tb spacer and cowl hood might be able to run ev1 or ev6.
cool intake
Reply
Old May 17, 2022 | 06:34 PM
  #5  
arrg's Avatar
Junior Member
15 Year Member
 
Joined: Nov 2009
Posts: 18
Likes: 4
Re: Edelbrock 3502 Multiport intake. Any thoughts?

I have one in my truck. Fire away with the questions.
Reply
Old May 17, 2022 | 10:58 PM
  #6  
Fast355's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Jan 2005
Posts: 10,450
Likes: 510
From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Ran one on my G20 van for a while.
Reply
Old May 18, 2022 | 12:18 AM
  #7  
robertfrank's Avatar
Thread Starter
Supreme Member
20 Year Member
Liked
iTrader: (27)
 
Joined: Apr 2004
Posts: 3,001
Likes: 62
From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Re: Edelbrock 3502 Multiport intake. Any thoughts?

How did or do you guys like it? What would you say the pros and cons were?
Reply
Old May 18, 2022 | 09:30 AM
  #8  
arrg's Avatar
Junior Member
15 Year Member
 
Joined: Nov 2009
Posts: 18
Likes: 4
Re: Edelbrock 3502 Multiport intake. Any thoughts?

So, kinda like you, I stumbled upon mine for $50. I wasn't planning on a MPFI conversion at the time, but at that price, I thought "why not".

Pros: I could use Pro-Flo XT fuel rails that I already had from another project. All the accessory brackets/lines bolted up. It has a CARB EO#, so it might have a chance of passing emissions if I ever move somewhere that requires that.

Cons: Won't support larger than a 46mm TB without some grinding. The ports are stock size and the manifold barely had enough material to seal a 1205 gasket that my heads needed.

Overall, it was the easiest/cheapest path for me to go from TBI to MPFI, but I think I'm probably sacrificing some power for that ease of use.
Reply
Old May 18, 2022 | 07:23 PM
  #9  
Fast355's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Jan 2005
Posts: 10,450
Likes: 510
From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Originally Posted by robertfrank
How did or do you guys like it? What would you say the pros and cons were?
Mine was a Vortec pattern and I replaced the TBI setup on a carb intake with it before I obtained a Vortec TPI base. The con for me was the pico injectors. I ended up using short style GM 5.3 Vortec injectors. I had a 2" TBI on mine and its large foot print required a large foot print open center TBI spacer to seal the extra wide IAC passageways.
Reply
Old May 18, 2022 | 10:17 PM
  #10  
robertfrank's Avatar
Thread Starter
Supreme Member
20 Year Member
Liked
iTrader: (27)
 
Joined: Apr 2004
Posts: 3,001
Likes: 62
From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Originally Posted by Fast355
Mine was a Vortec pattern and I replaced the TBI setup on a carb intake with it before I obtained a Vortec TPI base. The con for me was the pico injectors. I ended up using short style GM 5.3 Vortec injectors. I had a 2" TBI on mine and its large foot print required a large foot print open center TBI spacer to seal the extra wide IAC passageways.
where can I find those Injectors? What is their flow rating?
Reply
Old May 19, 2022 | 03:38 PM
  #11  
arrg's Avatar
Junior Member
15 Year Member
 
Joined: Nov 2009
Posts: 18
Likes: 4
Re: Edelbrock 3502 Multiport intake. Any thoughts?

I used Bosch 0280158191 injectors on mine. They're a short style, flex fuel injector from Ford's 3.7L engine. 31.4 lb/hr @ 43.5 psi
Also, unless you plan to run a TB spacer, you do need a short injector. Otherwise, the throttle arm on the TB hits the fuel rail.

Last edited by arrg; May 19, 2022 at 03:46 PM.
Reply
Old May 20, 2022 | 06:42 PM
  #12  
robertfrank's Avatar
Thread Starter
Supreme Member
20 Year Member
Liked
iTrader: (27)
 
Joined: Apr 2004
Posts: 3,001
Likes: 62
From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Just thought I'd post another update....

I'm trying to be as creative as possible with this so.... from what I've read, you needed to run the shorter style PICO injectors and edelbrock rails for this manifold. Well, I don't feel like spending over $400 for new rails and injectors so I modified a set of stock LT1 fuel rails and did a little grinding on the manifold itself. Turned out perfectly although I'm covered in aluminum dust lol. I need to drill holes in the bottom of the rails so I can mount them to the manifold. This will allow the use of a set of Bosch 3 24lb injectors I plan on getting. I'll need to get some large taps so I can fit these for AN fittings.





Reply
Old Jun 11, 2022 | 01:41 PM
  #13  
Tuned Performance's Avatar
Sponsor
20 Year Member
Community Builder
Community Influencer
Community Favorite
iTrader: (95)
 
Joined: Dec 2004
Posts: 16,930
Likes: 1,017
From: Mile High Country !!!
Car: 1967 Camaro, 91 z28
Engine: Lb9
Transmission: M20
Axle/Gears: J65 pbr on stock posi 10bolt
Re: Edelbrock 3502 Multiport intake. Any thoughts?

https://www.ebay.com/itm/25557635623...mis&media=COPY

one for cheap on eBay
Reply
Old Jun 13, 2022 | 09:05 AM
  #14  
Bill Chase's Avatar
Member
5 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2019
Posts: 177
Likes: 5
Re: Edelbrock 3502 Multiport intake. Any thoughts?

Originally Posted by robertfrank
Just thought I'd post another update....

I'm trying to be as creative as possible with this so.... from what I've read, you needed to run the shorter style PICO injectors and edelbrock rails for this manifold. Well, I don't feel like spending over $400 for new rails and injectors so I modified a set of stock LT1 fuel rails and did a little grinding on the manifold itself. Turned out perfectly although I'm covered in aluminum dust lol. I need to drill holes in the bottom of the rails so I can mount them to the manifold. This will allow the use of a set of Bosch 3 24lb injectors I plan on getting. I'll need to get some large taps so I can fit these for AN fittings.




just an fyi, you can purchase rail extrusion by the inch from rps and others very affordably, and have them drilled, reamed to final size for cheaper than you may suspect. Then make your own rail stands or mounts. I've read posts saying the lt1 rails were the same spacing as most aftermarket intakes. Playing with pieces on a bench while waiting for parts a couple years ago I found the stock lt1 injector spacing was definitely not the same as the miniram, not the same as the first tpi, or Holley EFI single plane. Close, but not the same and when you have 43-58 or more psi of gasoline head pressure in the rails having an injector cocked sideways 80-100 thousandths is not good. It's best to have the rails laid out to precisely match the intakes injector holes and keep a tighter tolerance. 400 bucks seems like a lot of money for rails until it costs you an entire car when it burns to the ground. They don't have to be ultra precise, but they do have to be reasonably close. The 93-96 lt1 intake rails I tried on my miniram had the injector pairs splayed out and the spacing was way wrong, visibly wrong. Please be careful when mixing and matching components like this. Custom rails are a bargain when you consider the bad things that can happen.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Thirdvert89
Engine/Drivetrain/Suspension Parts for Sale
0
Feb 28, 2019 11:32 PM
Gallileo60
TBI
19
Apr 12, 2007 07:04 AM
kronos
Engine/Drivetrain/Suspension Parts for Sale
4
Mar 12, 2007 02:48 PM
91-Z-Speed
Aftermarket Vendor Review
1
Aug 20, 2002 04:39 PM




All times are GMT -5. The time now is 06:33 PM.