In reply to MotorsportsGordon :
That's really interesting, is that for street driving or on track?
In reply to MotorsportsGordon :
That's really interesting, is that for street driving or on track?
ddavidv said:Holley Sniper kit for cars with hopeless OEM carb setups (Ford six cylinders come to mind). But...
The cost/benefit for a street driven car doesn't make sense, IMO. Carbs are just toilets for fuel. They really aren't these mystical beasts most people think they are. Tuning is really pretty easy. This is just one of several videos Luke Finley has about carb and ignition tuning: Holley & Edelbrock carb tuning. The main tuning tool is your vacuum gauge. Tony DeFeo shows you what to do here: Fine tuning with a vacuum gauge.
I'd rather turn screws to tune than wire in sensors.
I was with you for a very long time. The thought of wires and sensors plus tuning via lap top turned my stomach.
Eventually I left the dark side and come over to the light.
I used to go to the race track with a calibrated Air density gauge, jets, air Correction meters , needles etc. and I'd chase air density all weekend. Hard enough on a 6 cylinder. Nuts on 12.
Plug in the lap top and it's a simple matter to find where you want to go richer or leaner and punch a few keys, as the British say; Bobs your Uncle.
The great deal is once you're hooked up most systems are self learning. That is, crank the engine over a few times and it will set all the parameters itself. It's running!!!! You get to fine tune it. Tuning is the same except you do it with a few key strokes instead of replacing Jets and Needles.
frenchyd said:In reply to MotorsportsGordon :
That's really interesting, is that for street driving or on track?
Street mainly to be able to use pump gas
now John Greenwood used kinsler cross ram mechanical fuel injection on his wide body corvette race cars in the mid 70s
Another downside to carbs I'm not hearing discussed is fuel slosh during high g maneuvers (cornering and braking). Tuning for good driveability on the street is one thing, but for HPDE use there's a whole additional set of dynamic conditions that require addressing. Holley style with baffles, appropriate float level, slosh tubes, etc can be made to work but does add a layer of complexity over tuning for the street.
Run away from an Edelbrock carb for autocross or track day use. Research details on what is needed for Holley style carbs. I think some of the tuning books touch on this.
I went port EFI with Megasquirt for my SBC equipped autox car. Super happy with how it turned out. I've tuned carbs but much prefer to plug in a laptop than remove fuel bowls and change jets.
In reply to MotorsportsGordon :
If you want great performance for cheap money use E85. It's a pump grade fuel with about 100 octane but starts out giving you about 10% more power ( the higher the compression the more power it adds. I pay $2.79/9 a gallon for it. 87 octane is $3.99/9 and 91 octane premium starts at $4.35/9 so it's a serious money saver while being better for your engine. It runs cooler and stays cleaner.
Plenty of articles confirming my statements including GRM. There is a free ap for your phone that will let you find it.
In reply to frenchyd :
E85 is definitely good stuff for power. The challenge is, unless you've got a setup that can also run on E10/E0, it's tough to use E85 on a street car you want to take out of your home area. In some places it's either hard to find or just unavailable.
On many of the modern standalone E85 doing flex fuel is rather painless.
Apparently the carb isn't a Holley. They're (the seller) is going to e-mail me the entire list of specs, but apparently it's a carb from a smaller company owned by former Holley employees.
Went to bring it to the shop yesterday and made it 5 miles before it quit. I think it was electrical, as if the alternator wasn't charging.
In reply to SKJSS (formerly Klayfish) :
There are dozens of Holley-based carbs. Over the years Holley was pretty loose with their patents and several companies started taking their components and improving them. Some of them like Quick Fuel are mostly built with exact copies of Holley body parts that have been drilled or machined differently. Others like Demon started out by modifying Holley stuff. They eventually moved to making some of their own fuel bowls and metering blocks, and now they primarily use proprietary parts. About the only thing from the Holley catalog that fits in a Demon carb are the jets and floats/seats.
So when we say it's a Holley 4150, we're kinda saying "it's a Kleenex." It may be a different brand, but it's a 4150-style construction. Or it could also be considered like calling a Factory Five Mk4 Roadster a "Cobra." It isn't a true AC Ace/Cobra, but it's an aftermarket piece done in a Cobra style.
I'm anxious to see what it is
JMcD said:Another downside to carbs I'm not hearing discussed is fuel slosh during high g maneuvers (cornering and braking). Tuning for good driveability on the street is one thing, but for HPDE use there's a whole additional set of dynamic conditions that require addressing. Holley style with baffles, appropriate float level, slosh tubes, etc can be made to work but does add a layer of complexity over tuning for the street.
The car in question has been running for sometime and likely doesn't have an issue; the OP pointed out that the car runs well on track.
In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
rslifkin said:In reply to frenchyd :
E85 is definitely good stuff for power. The challenge is, unless you've got a setup that can also run on E10/E0, it's tough to use E85 on a street car you want to take out of your home area. In some places it's either hard to find or just unavailable.
Living in the Midwest it's all around. But I'd be surprised if it's not available in every state. Too many hot rodders / drag racers, etc. absolutely love the stuff. Have you tried using the AP?
Curtis73 (Forum Supporter) said:In reply to SKJSS (formerly Klayfish) :
There are dozens of Holley-based carbs. Over the years Holley was pretty loose with their patents and several companies started taking their components and improving them. Some of them like Quick Fuel are mostly built with exact copies of Holley body parts that have been drilled or machined differently. Others like Demon started out by modifying Holley stuff. They eventually moved to making some of their own fuel bowls and metering blocks, and now they primarily use proprietary parts. About the only thing from the Holley catalog that fits in a Demon carb are the jets and floats/seats.
So when we say it's a Holley 4150, we're kinda saying "it's a Kleenex." It may be a different brand, but it's a 4150-style construction. Or it could also be considered like calling a Factory Five Mk4 Roadster a "Cobra." It isn't a true AC Ace/Cobra, but it's an aftermarket piece done in a Cobra style.
I'm anxious to see what it is
Gotcha, makes sense. Just spoke to the PO. He's working on getting me all the specifics for cam, carb, etc... they had been posted in the original for sale ad, but I didn't copy it before they took the ad down. Here's a basic list he sent....
MOTOR: GM block – 355 CI 2-bolt mains
Ceramic lined pistons
Crane cam
Summit 375-400 top end kit
Aluminum heads
Aluminum intake
Roller rockers
600 CFM carb
Smaller belt pulley
Aluminum flywheel
355 rear end – rebuilt by Van Steel
Drive shaft – Rebuilt by Van Steel
3-row aluminum radiator
Dual electric fans
SUSPENSION: Van Steel tubular upper A arms
Modified lower A arm with poly bushings to accept shocks
Front BB coil springs
Rear coil over conversion kit
Off set trailing arms
Rebuilt bearing assemblies
QA1 Adjustable shocks
ARP 3” racing studs
Front and Rear sway bars
INTERIOR: Recaro seats
Shark Bar harness bracket
5-point harness
Temp gage
Oil Pressure gage
Fuel gage
Factory 4-speed manual transmission
Bassett racing wheels – 15x8 front
15x10
bentwrench said:In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
Likely, but define better?
It's not going to make more peak power with EFI and even if it did it would be minimal.
It would likely make more power across a broader range of throttle settings at given RPM but the butt dyno likely wouldn't notice.
This is an HPDE car, so the car simple needs to run well..................optimizing that last 3% isn't a priority.
Sorry for being such a pedant on this one but we tend to get into these discussions that, intended or not, would give an outsider the impression that carbs are some sort of horrible cantankerous devices that can never be made to work extremely well.
In reply to SKJSS (formerly Klayfish) :
That's a really nice set up.
Tom1200 said:JMcD said:Another downside to carbs I'm not hearing discussed is fuel slosh during high g maneuvers (cornering and braking). Tuning for good driveability on the street is one thing, but for HPDE use there's a whole additional set of dynamic conditions that require addressing. Holley style with baffles, appropriate float level, slosh tubes, etc can be made to work but does add a layer of complexity over tuning for the street.
The car in question has been running for sometime and likely doesn't have an issue; the OP pointed out that the car runs well on track.
I definitely missed a bit of that in the first post but if you're having to do things like set the float level after a rebuild, it's worth knowing that you can't always expect straight line tuning and driveability to match on track when it come to carbs.
JMcD said:I definitely missed a bit of that in the first post but if you're having to do things like set the float level after a rebuild, it's worth knowing that you can't always expect straight line tuning and driveability to match on track when it come to carbs.
Very true but the specs for carbs are usually damn close so you can set it and forget it. The internet has made things really easy; whether it's CV, Weber DGV or DCOE, SUs or bike carbs there's a forum out there that will get you 99% of the way there.
Also note reading the manual does wonders.
No info about the carb in that list 
Very little info about anything, really.
bentwrench said:In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
I can promise you that is not always the case. For most of the 90s and early 2000s, carbs were still crushing aftermarket EFI and many factory EFI setups.
This is like saying that all IKEA furniture will be good quality. Since a huge variable is how it's assembled, that's a big if. EFI can be wonderful if you have the knowledge to tune it right and fix all the bugs. Both systems have benefits and drawbacks, but neither one is intrinsically superior in every way. A properly tuned carb will beat a roughly-tuned EFI just as easily as a properly tuned EFI will beat a poorly tuned carb.
But to say that properly tuned EFI will always beat a properly tuned carb is just not really accurate.
surely out of all of the iterations of small block over the years, there's a factory injection manifold that could work with port injection and a nice big TB?
Curtis73 (Forum Supporter) said:bentwrench said:In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
I can promise you that is not always the case. For most of the 90s and early 2000s, carbs were still crushing aftermarket EFI and many factory EFI setups.
This is like saying that all IKEA furniture will be good quality. Since a huge variable is how it's assembled, that's a big if. EFI can be wonderful if you have the knowledge to tune it right and fix all the bugs. Both systems have benefits and drawbacks, but neither one is intrinsically superior in every way. A properly tuned carb will beat a roughly-tuned EFI just as easily as a properly tuned EFI will beat a poorly tuned carb.
But to say that properly tuned EFI will always beat a properly tuned carb is just not really accurate.
Sorry, Curtis, there's no way a carb could handle the emissions changes from 1996 on- there's a real reason that EFI was the path taken over carbs. I appreciate your enthusiasm for carbs, but lets not make stuff up because of that. There may be a handful of great carbs that can be the limited EFI systems out there- but it's very much not a blanket thing.
Curtis73 (Forum Supporter) said:bentwrench said:In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
This is like saying that all IKEA furniture will be good quality. Since a huge variable is how it's assembled, that's a big if. EFI can be wonderful if you have the knowledge to tune it right and fix all the bugs.
This is the crux of the matter and where I fell off the edge of the world.
I struggled with the Fitech and went back to a carb. But the problems did not magically go away with the carb. That led me to discover that there was an ignition breakdown and exhaust air leak. Both those made it impossible for the Fitech to do the job. The thing is, the Fitech was a new variable that obscured the issues and sent me down a button-pushing tuning rabbit hole that led nowhere. Of course I did not want to abandon the investment and spend more money on a carb so that ate years of time and a lot of frustration,
The Fitech might work if I put it back on. However, with time on the forums I have discovered what I should have known from the start: Fitech is a small company that went to market with their latest prototype and has been playing quality catch-up ever since. Firmware and hardware have been evolving not to improve performance, but to fix reliability issues. The internal wiring is very prototype quality build. They originally had two relays inside the TB that created too much heat; those have now been expernalized. Electronic failures seem to be troubling both Fitech and Holley; might just be a reality of trying to operate electronics in an environment where you should not run electronics ( hot vibrating )
I do miss the data logging from the EFI. Currently have to settle for a wide band O2 sensor to tell me what the Holley is doing. But even then, I have to take the data with a grain of salt because the Fitech taught me that a miniscule exhaust leak will turn the O2 sensor into a liar. Stick the shop vac on the tailpipe and soapy water on the header flanges to be sure. Ever meet a set of headers that DO NOT leak?
Curtis73 (Forum Supporter) said:bentwrench said:In reply to Tom1200 :
I can guarantee it would run better with a proper EFI...
I can promise you that is not always the case. For most of the 90s and early 2000s, carbs were still crushing aftermarket EFI and many factory EFI setups.
This is like saying that all IKEA furniture will be good quality. Since a huge variable is how it's assembled, that's a big if. EFI can be wonderful if you have the knowledge to tune it right and fix all the bugs. Both systems have benefits and drawbacks, but neither one is intrinsically superior in every way. A properly tuned carb will beat a roughly-tuned EFI just as easily as a properly tuned EFI will beat a poorly tuned carb.
But to say that properly tuned EFI will always beat a properly tuned carb is just not really accurate.
I was very much where you are for a very long time until I really understood EFI.
A light bulb moment came when I realized that EFI is just a simple carb.
It squirts out a fixed amount of fuel and let's the cams and valves decide when it goes in. Just like a carb.
Only the most recent, newest injection system is sequential. And all that does is save .000001 nano particles of exhaust emissions. ( terrible exaggeration because I don't know nor do I care).
I've tuned so many carbs over my lifetime because what works on the street doesn't work on the race track. Nope you can't just richen up the carb. You have to richen it in the right places and then deal with fuel sloshing around. It's fine to adjust floats when you're standing in a garage or driving down the street.
But when you are at the absolute edge of control and your eyeballs actually feel like they're being pulled out of your head all fluids act the same way . They just want out and go looking for it.
Heck, Even NASCAR who still plays with push rods has gone to EFI
The big difference is instead of getting out the tools and drills. You open up the lap top and put a few key strokes in
You don't need to be a computer programmer. Just change numbers in a box. The computer will even tell you where and how much. If you can tune a carb, once you get over the fear a laptop is your friend.
MotorsportsGordon said:frenchyd said:In reply to MotorsportsGordon :
That's really interesting, is that for street driving or on track?
Street mainly to be able to use pump gas
now John Greenwood used kinsler cross ram mechanical fuel injection on his wide body corvette race cars in the mid 70s
I can still tune a Hilborn style mechanical Fuel Injection. Vintage racing allows mechanical fuel Injection. And yes it's better than carbs.
frenchyd said:I can still tune a Hilborn style mechanical Fuel Injection. Vintage racing allows mechanical fuel Injection. And yes it's better than carbs.
I have the exact opposite opinion. I have had good success on WOT or NOT type cars, but transitions generally are a lot better on EFI and *gasp* carbs. On road race setups it probably depends a lot on setup/driver/goals for how well it works. Also seems to work better on setups that have a relatively flat torque curve where you are wanting to use it. One of my favorite little projects is to add sensors/logging to mechanical and carbd cars to tune them. After looking at it you can see what "feels good" vs what's "actually good" if you want to take economy, etc, into account.
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