Has anyone on here ever built or designed a custom intake for a smallblock chevy? Here's my ideas and plans any help or info would be greatly appreciated. I'm currently building a 1991 tbi 350 into a 383cuin custom efi beast. I already bought my rotating assy, camshaft and cyl heads. The rotating assy is a balanced eagle 383 one piece kit that has 10.7:1 comp pistons, the heads are RHS protorker 170cc vortec styleand the cams a Lunati 60101. Here's where I would like some advice, I've been looking and researching the different efi systems on the market and have pretty much decided to do my own. I already ordered a megasquirt 3 efi controller and a transmission controller for the electronics. Now heres where i'm needing the help, I've been looking at the different ram style efi intakes and have decided to build my own using a Weiand tunnelram intake base modified for injectors and a custom intake plenum designed to use the throttlebody from an ls1. The major questions I have are what should the plennum volume be and does anyone have the foorprint measurements for the ls1 tb? I have found info from a couple places about the holley ramjet intake plenum volume being 246cuin which is about 65% of my total cuin disp, should I stick with this disp or use a different percentage? My delima is that I'm building this thing for low end grunt rather than high end hp. Also I want to go sequential port efi, how can I use a cam sensor with this engine?

Any help or inste is greatly appreciated,
Thanks

 

I think the answer for the cam sensor and/or sequential port is in this sticky IIRC,

https://www.thirdgen.org/forums/tpi/...-cylinder.html

I`ve seen some guys on this board coming up with something similar.

https://www.thirdgen.org/forums/alte...t-efi-intakes/

Hope that helps or am i completely misunderstanding you?If you want low end grunt whats wrong with whats out there already?

 

Sounds like a lot of work for little gain.
Why not buy the HSR ( is Weiand tunnel ram converted to EFI ) and either modify the plenum or build a custom one to suit the LSX TB?

http://www.summitracing.com/parts/WND-7540/

Vortec timing cover has provision for crank angle sensor

Ask the same question over on 3rd Gen Alt Intakes
https://www.thirdgen.org/forums/alte...t-efi-intakes/

 

My compnay sells a line of custom made intakes. All sheet metal. PM me if you're interested. However, be ready to open your wallet, we get between $3k AND $4K.

Some samples:





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thinking of one of these for my car:

IMG_0425rev0.jpg?t=1223260550
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Not cheaap $3000-4000 each, but BEAUTIFUL work.

 

I just came

 

I'd say this will vary on application to application because i've seen small plenum cars do very well (carb style EFI intakes with elbows) and then again i've seen large plenum cars work great too. Throttle response may be different between the two. Definately requires different tip in type tuning as a large inch motor will suck a small plenum "empty" quicker than a large plenum car so the pump shot needs to be different.

The general concensus is 1.5 to 2 times cubic inches. Holley stealth ram basically is what your recreating. HSR I cant recall what the dimensions were but I think its 480 or so cubic inches of volume which is around 1.27 times a 383. Not a bad ratio to have.

Proflo XT by edelbrock is similar to HSR but with LSx throttlebodys. Plenum volume however looks smaller.

I have read from some guys that you cant have enough plenum volume with EFI so going larger isnt a bad idea. I just dont have any data to back up the claims or theories.

 

Hey jsup those nice looking intake systems would go real good on a set of the latest AFR heads.

 

LOL!

Anyway, to the OP, i notice you have 170cc runner vortecs with 10.7 to 1 compression and a fairly large flat tappet cam. You may have some pump gas issues with that but the cam being so large will help. I'd go larger on the heads if you could. Why not get a set of 200cc type heads?

 

HA! That was funny. These are out of the AFR league.

If the hype is true, may be able to break the sound barrier. Those intakes make one forget about the head.....

 

Holy crap! The intake would cost more than the rest of my engine! They are NICE, no doubt! One off, built to order I would bet.

 

Yep. Not unreasonably priced compared to the rest of the market.

 

You are correct! And worth the price, I am sure. BEAUTIFUL Workmanship! Aerospace quality, but just out of my league! I would want to just keep it in a display case and charge admission to look at it!