I don't think I really need to say this but if you mod you carburetor for blow through, you void any warranty that applies to the carb. DO AT YOUR OWN RISK! If you missed out on part 2, there it is! ua-cam.com/video/IzVyM-tTw_M/v-deo.html
You need to fabricate vent tube extensions on your carb. Run them into your bonnet a few inchs. Then you can rejet the carb closer to the stock jetting. I run a Procharged 355 on the street. Drives and idles great. Proform 750 center section, annular discharge with billet base plate.
Very nice, I havnt experimented with the extensions yet. My truck is a manual 5 speed on offroad tires so the tuning gets much trickier during low RPM heavy throttle. I know the extensions help under boost but I havnt seen them make any difference while driving around off boost
@@adamballinger1358 yea I tried messing with the air bleeds and it just scrambled the hole tune, I was able to get it running to being streetable with just jets, ifr that early activation of the secondaries and that's it
What about boosting the 2nd and 3rd 2GC carbs on a Pontiac tripower setup? You can adjust linkage for tip in. I have mine at 50% on one car and 60% on another.
The issue with boosting multiple carbs is getting them to flow the same amount of fuel for good fuel distribution. I tried it on a dual quad and it didn't really work well. Some cyls were going dead lean
I always take cylinder placement into consideration when thinking about heat retention in that particular part of the block, and which cylinders would fail first if it goes lean. With this its safe to assume the hottest leanest cylinders will fail first. This was applied when I was analyzing the engine failure in a turbo 5.3L that had rear cylinder failure on a VERY under-fueled setup. I have yet to test injectors, but I believe the design of the dead-head fuel rail on the LS car manifold, paired with boost, and a return line added in a poor location leads me to believe the rear two went lean and failed due to either vapor lock or poor circulation and flow at the end of the rail.
After 3 videos, I am starting to get a base line on blowthru 101. The picture of idle to transition to part throttle cruise to full power is a bit clearer. I have always run mild VS carbs, to there is a bit to learn there too, but that's ok too.
For my demon I used the Alcohol metering blocks and for the proform I used the factory E85 metering blocks. You can acomplish it by drilling out the stock metering block. I'll make a video on that for you guys
NightWrencher hello, I have question possibly you can help me out with , for one I know very little about carburetors , my question is I have a 327 , bored 30 over with a Holley 650 double pumper 80670-4 1308 the carburetor was running rich buddy of mine changed the jets to 63 primary 65 Sec,and timed the motor seemed to help a little …But now the problem is when I crack the Secondary’s it want too drop Rpm’s wop bam wop bam …..lol I don’t know how else to exsplain it lol , but the damn thing idles fine and smooth in the primary stage until cracked into Secondary stage do you have any suggestions that might help Nightwrencher , my buddy was saying something about a lighter Acc pump secondary spring dose this make sense or is just a bunch of Mumbo Jumbo waste of time , then he was telling if that didn’t work that i probably need 750 dbl ….I just don’t want to waste any more time or money trying to figure this out the cam in the motor is 560 ? ,so I guess Night Wrencher if anybody could possibly give the right path would hopefully be you ….Thanks Nightwrencher I really appreciate your time and help……Ron 👍
Hey Ron, first off thats not a 650 double pumper. Thats a dual feed 670cfm vacuum secondary carburetor, not a double pumper. Double pumper means accelerator pump on the primary and secondaey bowls. If it has a big vacuum pod on the side then its a vacuum secondary carburetor. Second, since its a vacuum secondary carburetor, even if you suddenly stomp on the gas, there is a delay before the secondaries keep up with the primaries. What I think your buddy meant was a lighter vaccum diaphram spring. In my opinion, that would make the problem worse. Sounds like youre leaning out when the secondaries come in so that would cause the shaking/popping. A lighter secondary spring means the secondaries come in faster which would cause the lean spike to get worse. I would go with a HEAVIER secondary spring so the secondaries open smoother but also jet up 3-4 sizes in the rear and then go from there
@NightWrencher Nice! That's a great idea! How are your crusing AFR's? Like hwy speed(50-60mph) I've been trying to keep afresh leaner the 12.5 just crusing. But then really runinto issues with trasntion (have BRPV up front.
I try to keep my cruising AFR around 13.5-14. I even tow with my truck for several hundred miles at a time and highest I see is 14.2. Going up steap grades with a 3k lb trailer I go into boost without issue(steady 2-3lbs all the way up). Make sure you leave yourself enough slack in the primaries to prevent going into the secondaries when not needed. I have my secondary idle screws out about an 8th of a turn.
I don't think I really need to say this but if you mod you carburetor for blow through, you void any warranty that applies to the carb. DO AT YOUR OWN RISK!
If you missed out on part 2, there it is! ua-cam.com/video/IzVyM-tTw_M/v-deo.html
You need to fabricate vent tube extensions on your carb. Run them into your bonnet a few inchs. Then you can rejet the carb closer to the stock jetting. I run a Procharged 355 on the street. Drives and idles great. Proform 750 center section, annular discharge with billet base plate.
Very nice, I havnt experimented with the extensions yet. My truck is a manual 5 speed on offroad tires so the tuning gets much trickier during low RPM heavy throttle. I know the extensions help under boost but I havnt seen them make any difference while driving around off boost
You were right it is mind blowing stuff, the huge ifr size makes sense now
Theres even more info but its 🤐
@@adamballinger1358 yea I tried messing with the air bleeds and it just scrambled the hole tune, I was able to get it running to being streetable with just jets, ifr that early activation of the secondaries and that's it
Killer Info Man. Im just getting into Carb Tuuning and this is GOLD even for a Novice like me!
Thank you! I hope it helps in the future!
What about boosting the 2nd and 3rd 2GC carbs on a Pontiac tripower setup? You can adjust linkage for tip in. I have mine at 50% on one car and 60% on another.
The issue with boosting multiple carbs is getting them to flow the same amount of fuel for good fuel distribution. I tried it on a dual quad and it didn't really work well. Some cyls were going dead lean
I always take cylinder placement into consideration when thinking about heat retention in that particular part of the block, and which cylinders would fail first if it goes lean. With this its safe to assume the hottest leanest cylinders will fail first. This was applied when I was analyzing the engine failure in a turbo 5.3L that had rear cylinder failure on a VERY under-fueled setup. I have yet to test injectors, but I believe the design of the dead-head fuel rail on the LS car manifold, paired with boost, and a return line added in a poor location leads me to believe the rear two went lean and failed due to either vapor lock or poor circulation and flow at the end of the rail.
Yeah, plug readings have to be taken very seriously especially when youre building that much cyl pressure
It's smart to point out that fuel injection and carburetors can fail in different ways yet lead to similar consequences or damage.
After 3 videos, I am starting to get a base line on blowthru 101. The picture of idle to transition to part throttle cruise to full power is a bit clearer. I have always run mild VS carbs, to there is a bit to learn there too, but that's ok too.
Just curios on which metering block you use for e-85 , do you use the ones drill for alcohol or gas jetting?...Thanks
For my demon I used the Alcohol metering blocks and for the proform I used the factory E85 metering blocks. You can acomplish it by drilling out the stock metering block. I'll make a video on that for you guys
@@NightWrencher Thanks for that quick response, I'll be watching for it👍.
NightWrencher hello, I have question possibly you can help me out with , for one I know very little about carburetors , my question is I have a 327 , bored 30 over with a Holley 650 double pumper 80670-4 1308 the carburetor was running rich buddy of mine changed the jets to 63 primary 65 Sec,and timed the motor seemed to help a little …But now the problem is when I crack the Secondary’s it want too drop Rpm’s wop bam wop bam …..lol I don’t know how else to exsplain it lol , but the damn thing idles fine and smooth in the primary stage until cracked into Secondary stage do you have any suggestions that might help Nightwrencher , my buddy was saying something about a lighter Acc pump secondary spring dose this make sense or is just a bunch of Mumbo Jumbo waste of time , then he was telling if that didn’t work that i probably need 750 dbl ….I just don’t want to waste any more time or money trying to figure this out the cam in the motor is 560 ? ,so I guess Night Wrencher if anybody could possibly give the right path would hopefully be you ….Thanks Nightwrencher I really appreciate your time and help……Ron 👍
Hey Ron, first off thats not a 650 double pumper. Thats a dual feed 670cfm vacuum secondary carburetor, not a double pumper. Double pumper means accelerator pump on the primary and secondaey bowls. If it has a big vacuum pod on the side then its a vacuum secondary carburetor. Second, since its a vacuum secondary carburetor, even if you suddenly stomp on the gas, there is a delay before the secondaries keep up with the primaries. What I think your buddy meant was a lighter vaccum diaphram spring. In my opinion, that would make the problem worse. Sounds like youre leaning out when the secondaries come in so that would cause the shaking/popping. A lighter secondary spring means the secondaries come in faster which would cause the lean spike to get worse. I would go with a HEAVIER secondary spring so the secondaries open smoother but also jet up 3-4 sizes in the rear and then go from there
If you have the secondary side IFR that much larger then the primary. The idle mix screw (in the secondary) can't be turned out hardly at all correct?
That is 100% correct
@NightWrencher Nice! That's a great idea! How are your crusing AFR's? Like hwy speed(50-60mph) I've been trying to keep afresh leaner the 12.5 just crusing. But then really runinto issues with trasntion (have BRPV up front.
I try to keep my cruising AFR around 13.5-14. I even tow with my truck for several hundred miles at a time and highest I see is 14.2. Going up steap grades with a 3k lb trailer I go into boost without issue(steady 2-3lbs all the way up). Make sure you leave yourself enough slack in the primaries to prevent going into the secondaries when not needed. I have my secondary idle screws out about an 8th of a turn.
👍👍💪💪
Double emojis, must of been a good video 🤔
Which F1 team you work for?
No F1 team unfortunately 😂
Your understanding of suspension dynamics suggests you sbold be
You got game . Step Strong Brother.