Anyone running EFI on a 512 stroker?

[andyf]

Not being argumentative, but there may be a power improvement via the interplay of the EFI and timing, making a "best case scenario tune" more likely.
At least that is what I would think.

Sometimes EFI makes more power, sometimes a carb makes more power. Typically if you have an engine that is designed for a carb and you put EFI on it then the power is roughly the same. EFI will make more power if you use a dedicated EFI intake but there aren't many of those around. At this point in time most people are running EFI on a carb intake so the power stays the same. EFI is much easier to tune (if you know what you're doing) so it can be a lot faster to get the engine to max power. Very few hot rodders ever full tune a carb/distributor combo because it is just too much work. But with EFI you can quickly home in on a tune.
I dyno tune EFI engines in half a day while carb/distributor engines take a full day or a day and half. If you have to recurve a distributor a couple of times then you're losing money. An EFI timing table can be reprogrammed in seconds while it takes an hour or more to recurve a distributor. Jetting a carb takes a lot longer than changing the target AFR table. If you have to tinker with the emulsion or air bleeds or transfer slots on a carb then you are into it for more than an hour. Even something like accelerator pump tuning can take a long time with a carb. Changing pump cams and nozzles is a chore. With EFI you look at the data log and add or subtract some fuel from the AE curve and you're done.

 

[biomedtechguy]

Sometimes EFI makes more power, sometimes a carb makes more power. Typically if you have an engine that is designed for a carb and you put EFI on it then the power is roughly the same. EFI will make more power if you use a dedicated EFI intake but there aren't many of those around. At this point in time most people are running EFI on a carb intake so the power stays the same. EFI is much easier to tune (if you know what you're doing) so it can be a lot faster to get the engine to max power. Very few hot rodders ever full tune a carb/distributor combo because it is just too much work. But with EFI you can quickly home in on a tune.
I dyno tune EFI engines in half a day while carb/distributor engines take a full day or a day and half. If you have to recurve a distributor a couple of times then you're losing money. An EFI timing table can be reprogrammed in seconds while it takes an hour or more to recurve a distributor. Jetting a carb takes a lot longer than changing the target AFR table. If you have to tinker with the emulsion or air bleeds or transfer slots on a carb then you are into it for more than an hour. Even something like accelerator pump tuning can take a long time with a carb. Changing pump cams and nozzles is a chore. With EFI you look at the data log and add or subtract some fuel from the AE curve and you're done.

ALL OF THAT is exactly what I was thinking of, knowing of examples of carbs making more power than the EFI that came after on "a build" that developed over time, several instances that I've read about or seen on TV.
This coming from the guy (me) who has SIX 2bbl carbs to deal with between 2 cars.
I have invested in BOTH carb arrays, the Rochester Tripower most recently having been sent to Dick Boneske, a master tuner of Tripower carb setups. I sent the build specs of the 421, cam card, etc. and Dick drilled passages, rejetted, and other voodoo...
Promax modded my 6bbl, making it run better now, and easier to mod and tune in the future, with my mind on the 541 stroker, and the Weiand P3690982 6bbl CrossFlow "Super Stock" old school intake.
My last move with the Rochester Tripower was letting Boneske mod them, now fine tuning is up to me, as is doing something, anything with the really nice, highly tunable Pertronix billet aluminum distributor w/Ignitor III module. ALL I've done is set initial no vacuum advance baseline timing, and checked it with the vacuum advance hooked up, and I believe there is a lot of performance improvement potential there, along with dialing in the Tripower.
There's a gorgeous "Tripower look alike" TBI/EFI setup, and it really does look like a Tripower, but turn key w/fuel pump, lines, tuning system, etc it's 8 grand!
I have seen a couple of jaw dropping beautiful Weiand 6bbl intakes like mine that are using the F&B Direct Port Injection setup, and ultimately having that intake become a "dry intake" eliminates the common, well known issues it has always had like fuel puddling and uneven distribution, fuel droplets coming out of suspension, etc.
I would LOVE to have it modded to Max Wedge ports, the EFI setup, plenum volume adjusted to work best with MY 541 stroker, and see what that could do, but I have over $1k in Promax parts in my 6bbl. That $1k is nothing compared to what the stroker will cost, including the BME aluminum block, and it's hard to not want to jump in with both feet and have F&B take it to the max, but I'm going to have a hard time getting the money together to finish the 541 build.

 

[JKByrnes]

Very nice!

 

[not so famous bob]

Very nice!

I aint trying to compete w/ any of these guys , but my setup is similar to urs, 505 w/ fast 2.0 .
Have to pump the pedal one time since going to a victor intake , before that I didnt .
Altho that could probly be tuned out of it from the drivers seat.
much titer package tho !

 

[biomedtechguy]

victor intake

POLISHED Victor intake! Very nice looking.
If I can make my Weiand P3690982 6bbl intake run well enough, I am DEFINITELY going to get it polished, because, well...see for yourself! (This one has carb spacers added)

Here's the F&B EFI version:

 

[1971]

I have a 505” that dynoed at 636hp/615lbft with a carb. I run the Holley super sniper fuel injection now and it’s been great. There’s guys who can remote tune them too and really get em dialed in

Remote tune? That's a thing? Are they connected to wifi or something, maybe hardwired to the net?

 

[ckessel]

I personally have not run it yet, but mine was built/run/tuned by Indy. Port injection with an AEM controller. 664HP/652TQ. This is the sister engine to the one Johnny Hunkins [Popular Hot Rodding/Mopar Muscle] has in the yellow Valiant.

 

[andyf]

Remote tune? That's a thing? Are they connected to wifi or something, maybe hardwired to the net?

Yes, remote tuning is possible. I have a buddy who does it all day long for customers around the world. The customer needs to have wifi in their shop or garage and then have a laptop hooked to the car. Can even use a cellphone as a hotspot and tune it while driving but the connection is usually iffy.

 

[Hemirunner]

Another vote here for the Holley Dominator EFI.

 

[andyf]

Considering stroking the 440, with the trick flow 240 heads, mild to moderate hydraulic roller cam, 10-10.5 CR and a EFI set up. Will go through a 727 with a gear vendors behind it. Looking for solid torque monster that I can spin to 6500 ish. Car will mostly be a cruiser/grand touring type car, but I want it to have some bite. My frame of reference is my GT500, which is 850 whp on her street tune. I don't need or expect the 512 to perform like that, but I do want it to have some serious grunt when I get on it. Hoping for something in the 600's/600's range. Just curious if anyone else has gone down this path? I like the thought of an EFI/computer controlled ignition with a dual synch distributor. I looked through many pages of 512 stroker threads, but didn't see a comparable build. Thanks in advance.

I have a RR in the shop right now with a 700 hp 505 engine that is getting fitted with a full Holley Sniper system. It should be running great when it leaves my shop.

 

[andyf]

Here is a Belvedere with a 505 running a Holley EFI system that I tuned. It runs 9.80's and is very reliable with the EFI system. They take it out of the trailer and go rounds. Almost zero maintenance required. Next year they should be going faster since they'll be stepping up to a bigger short block.

 

[alfaitalia]

Those on here saying that the FI wont make any more power......well maybe not at peak power (so the ultimate HP number might not gain much if at all) but you will gain power at other points in the rev range almost guaranteed. Setting a carb up for peak power is not so difficult but setting one up for good road manners with lots of torque throughout the range is much more difficult....those transition phases being the issue. The EFI will be adjusting the fueling to optimize the mixture for any different loading and driving satiations (even altitude and temperature) something that cant be done with constant carb tuning/jet changing. So on the dyno even the most basic EFI kit WILL give more power at certain points in the rev range than all but the most perfect carb set up and will adjust constantly to keep it close to perfect. So yes...maybe not much extra on the peak numbers....but possible quite a bit of extra "area" under the horsepower trace on the dyno....and that area is the difference between a peaky race car and a torquey street machine....even if the both produce the same max HPO/Tq figures. Just my 2 pence!!

 

[Derwud]

540 running Edelbrock Pro-Flo 4.. Dyno was 600hp and 700Ft/lbs with a Single plane and 950 CFM carb

 

[451Mopar]

Those on here saying that the FI wont make any more power......well maybe not at peak power (so the ultimate HP number might not gain much if at all) but you will gain power at other points in the rev range almost guaranteed. Setting a carb up for peak power is not so difficult but setting one up for good road manners with lots of torque throughout the range is much more difficult....those transition phases being the issue. The EFI will be adjusting the fueling to optimize the mixture for any different loading and driving satiations (even altitude and temperature) something that cant be done with constant carb tuning/jet changing. So on the dyno even the most basic EFI kit WILL give more power at certain points in the rev range than all but the most perfect carb set up and will adjust constantly to keep it close to perfect. So yes...maybe not much extra on the peak numbers....but possible quite a bit of extra "area" under the horsepower trace on the dyno....and that area is the difference between a peaky race car and a torquey street machine....even of the both produce the same max HPO/Tq figures. Just my 2 pence!!

On EFI with Ignition control, you also get more control over the ignition curve.
With sequential port injection like the the XT is able to do, you can also trim the fuel for each cylinder although you would need a way to monitor each cylinders exhaust (Temperature or O2 sensor.) With the XT TPI intake, the fuel air/fuel distribution should be pretty constant port to port compared to a out of the box single carb intake manifold.
The better EFI controllers can also replace several individual boxes you might be using, like Cooling fan controller, Rev-Limiter(s), Boost or NOS ignition retard, Exhaust O2 sensor gauge, Tachometer, Flex fuel alcohol percent sensor/fuel, traction control, lockup/overdrive (and electronic) transmission controller.