Single Plane EFI
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
..... FYI ... This is a crossram intake manifold that was available back in the late 60's early 70's Trans-Am heyday with single or dual quad tops ... the injectors are aimed at the mouth of the intake runners (inside the box) which then travel to the opposite side of the manifold and into the cylinder head ports ....... I'll get better pics up after the manifold comes back from the fab shop , including some shots of what it looks like under the lid ... the biggest obstacle here was keeping the fuel rails between the reinforcing structure on the underside of the hood when closed , and we did ...........
Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
That was a quite valuable intake manifold. Less than 1500 of them were ever sold to the public before Smokey and Edelbrock had a falling out over the royalty amounts.
FYI the SY-1 was never offered with (2) four top. Offy, MT, GM and Edelbrock all did offer (2) four Cross Rams at one time or another but the SY-1 was a single 4150 only.
I have one that I got back in 1989 (for $50.00) and have used it on a few engines.
It takes ALOT of carburation because of how big the plenum is. It makes a nice TQ curve and has good power output between 3500 RPM and 7000 RPM on a 350-360 inch engine. It's RPM limited on 380 and bigger inch engines and honestly it's sweet spot is engines that make between 450-550HP because of the small (relitive to todays racing intakes) runner cross section.
Good luck with it.
Will
FYI the SY-1 was never offered with (2) four top. Offy, MT, GM and Edelbrock all did offer (2) four Cross Rams at one time or another but the SY-1 was a single 4150 only.
I have one that I got back in 1989 (for $50.00) and have used it on a few engines.
It takes ALOT of carburation because of how big the plenum is. It makes a nice TQ curve and has good power output between 3500 RPM and 7000 RPM on a 350-360 inch engine. It's RPM limited on 380 and bigger inch engines and honestly it's sweet spot is engines that make between 450-550HP because of the small (relitive to todays racing intakes) runner cross section.
Good luck with it.
Will
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
That was a quite valuable intake manifold. Less than 1500 of them were ever sold to the public before Smokey and Edelbrock had a falling out over the royalty amounts.
FYI the SY-1 was never offered with (2) four top. Offy, MT, GM and Edelbrock all did offer (2) four Cross Rams at one time or another but the SY-1 was a single 4150 only.
I have one that I got back in 1989 (for $50.00) and have used it on a few engines.
It takes ALOT of carburation because of how big the plenum is. It makes a nice TQ curve and has good power output between 3500 RPM and 7000 RPM on a 350-360 inch engine. It's RPM limited on 380 and bigger inch engines and honestly it's sweet spot is engines that make between 450-550HP because of the small (relitive to todays racing intakes) runner cross section.
Good luck with it.
Will
FYI the SY-1 was never offered with (2) four top. Offy, MT, GM and Edelbrock all did offer (2) four Cross Rams at one time or another but the SY-1 was a single 4150 only.
I have one that I got back in 1989 (for $50.00) and have used it on a few engines.
It takes ALOT of carburation because of how big the plenum is. It makes a nice TQ curve and has good power output between 3500 RPM and 7000 RPM on a 350-360 inch engine. It's RPM limited on 380 and bigger inch engines and honestly it's sweet spot is engines that make between 450-550HP because of the small (relitive to todays racing intakes) runner cross section.
Good luck with it.
Will
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Safety Car
Joined: Apr 2005
Posts: 3,624
Likes: 431
From: Dale City VA
Alot of hard work went into it. Gonna be a real competitive engine I think.... I tried not to show "it's full potential" over there as some of the folks I race against were lurking.... but some of them other Cats on YB are pretty sharp and noticed right off that I was purposley killing alot of HP (at least on the dyno sheet I posted).
Time will tell if I can get the rest of the car where it needs to be or not.
My 1984 has always been carburated (during it's life as a race car). A Carburetor was just easier for me to make the kind of HP I needed to run with those guys.
My 1992 still has the 2925 Super Victor single plane EFI conversion.
Will
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
Thanks.
Alot of hard work went into it. Gonna be a real competitive engine I think.... I tried not to show "it's full potential" over there as some of the folks I race against were lurking.... but some of them other Cats on YB are pretty sharp and noticed right off that I was purposley killing alot of HP (at least on the dyno sheet I posted).
Time will tell if I can get the rest of the car where it needs to be or not.
My 1984 has always been carburated (during it's life as a race car). A Carburetor was just easier for me to make the kind of HP I needed to run with those guys.
My 1992 still has the 2925 Super Victor single plane EFI conversion.
Will
Alot of hard work went into it. Gonna be a real competitive engine I think.... I tried not to show "it's full potential" over there as some of the folks I race against were lurking.... but some of them other Cats on YB are pretty sharp and noticed right off that I was purposley killing alot of HP (at least on the dyno sheet I posted).
Time will tell if I can get the rest of the car where it needs to be or not.
My 1984 has always been carburated (during it's life as a race car). A Carburetor was just easier for me to make the kind of HP I needed to run with those guys.
My 1992 still has the 2925 Super Victor single plane EFI conversion.
Will
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
..... Thanks ... This one turned out nice ... can't wait to get it on the engine dyno and see how it compares to a couple of other intake ideas I'm working on ..... I'm hoping that the fuel injection will tame this beast ..... after looking under the lid I was amazed that ANY fuel ever made it down the runners in anything but pure liquid form ... But its the runner length that got my attention ........... Stay Tuned ! .........
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
BINGO!
I've been saying that for years...in a different context (called "CFI"). It is an excellent runner length, IMO and with the base you have you've circumvented the runner cross section issue...with the MPFI, you've also circumvented the fuel distribution challenges. Keep us posted!
PS I always day-dreamt about using this to solve CFI/Cross ram fueling issues, but keep it stockish/stealthy looking; Injector inside the plenum....
Hard to find/size injectors for your power level though.
I've been saying that for years...in a different context (called "CFI"). It is an excellent runner length, IMO and with the base you have you've circumvented the runner cross section issue...with the MPFI, you've also circumvented the fuel distribution challenges. Keep us posted!
PS I always day-dreamt about using this to solve CFI/Cross ram fueling issues, but keep it stockish/stealthy looking; Injector inside the plenum....
Hard to find/size injectors for your power level though.
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
... I also have an Offenhauser Crossram being set-up for EFI ... that one will be done quite a bit differently , fuel injector placement-wise ... the Offy has longer runners ............
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
..... I guess the crossfire IS a crossram ... the original idea was to build a long runner intake manifold that would fit under the hood ... kinda like a flat tunnel ram ... unfortunately , these were intended for carburetors and the design didn't lend itself to streetability , much like a tunnel ram back in the day ....... BUT , with EFI and injectors placing the fuel in a better place without needing to make so many sharp turns , I am confident that the mid-long runners and their better cross sectional area will make for some interesting dyno numbers .......... Stay Tuned ! ........
Safety Car
Joined: Nov 2009
Posts: 3,971
Likes: 340
From: Adelaide South Australia
..... I guess the crossfire IS a crossram ... the original idea was to build a long runner intake manifold that would fit under the hood ... kinda like a flat tunnel ram ... unfortunately , these were intended for carburetors and the design didn't lend itself to streetability , much like a tunnel ram back in the day ....... BUT , with EFI and injectors placing the fuel in a better place without needing to make so many sharp turns , I am confident that the mid-long runners and their better cross sectional area will make for some interesting dyno numbers .......... Stay Tuned ! ........
Good Luck !!
Thread Starter
Le Mans Master
Joined: Feb 2005
Posts: 6,475
Likes: 565
From: Clearwater Florida
..... I just got this one back from my welder/fabricator ... another Dyno test intake manifold ... Holley Strip Dominator that has been EFI'ed ............ .....
One thing to notice is the rearward position of the thermostat bridge ... plus , its LOOOOOW at only 2 1/2" above the china rail ..........
..... One thing to notice is the rearward position of the thermostat bridge ... plus , its LOOOOOW at only 2 1/2" above the china rail ..........
Last edited by C409; Jul 11, 2014 at 07:19 AM.