jbird72 Posted May 30 Posted May 30 So here we go got the fitting 1 inch spacer had to go with drop down air cleaner wich sucks... pic with and without put new carb on so far before timing got er dialed in gear bout 13 lbs vac per idle set screw on all 4 ...fast idle bout 1000 in gear nice lobe to her but weird thing fuel press gauge bouncing the old summit was loose and rattly so replaced with this in video. Gel type deal 1st one i ever had and as i was tuning carb would even up really weird 20250529_154009.mp4 3 Quote
jbird72 Posted May 30 Author Posted May 30 1 hour ago, jbird72 said: So here we go got the fitting 1 inch spacer had to go with drop down air cleaner wich sucks... pic with and without put new carb on so far before timing got er dialed in gear bout 13 lbs vac per idle set screw on all 4 ...fast idle bout 1000 in gear nice lobe to her but weird thing fuel press gauge bouncing the old summit was loose and rattly so replaced with this in video. Gel type deal 1st one i ever had and as i was tuning carb would even up really weird 20250529_154009.mp4 So mis printed earlier. Im only getting betwixt 10 and 11 at idle.....tried 2 diff gauges and have the vacumn gauge on back of carb. Ported vac...i recently used a borscope checked cylinders showed joe...still has original bore marks. Ran comp test on all cylinders with guage..did cold tho..but all 8 were within 5 to 10 of each other highest being 190...i understand has nothing to do with vacumn per say...so what an i missing. The highest i can get in gear while tuning was around 15 per screw. But when changed to diff screws wouldnt get much higher. Seemed that should be around 20 or higher. Its running good ..starts right up..has not been timed 100 percent yet and zero vacumn leaks whats goin on 2 Quote
jft69z Posted May 30 Posted May 30 Vacuum gauge needs to be attached to manifold vacuum for accurate readings. 3 Quote
jbird72 Posted May 30 Author Posted May 30 3 hours ago, jft69z said: Vacuum gauge needs to be attached to manifold vacuum for accurate readings. Sumbitch...i had it on front timed spark..ugg...different than my Vacumn sec...this has a port just for pvc in rear and i had the pvc in front ..ok easy peasy run pvc to rear. Itll look better than trans to full mani after tuned. Geeze... 3 hours ago, jft69z said: Vacuum gauge needs to be attached to manifold vacuum 2 Quote
jbird72 Posted May 30 Author Posted May 30 28 minutes ago, jbird72 said: Sumbitch...i had it on front timed spark..ugg...different than my Vacumn sec...this has a port just for pvc in rear and i had the pvc in front ..ok easy peasy run pvc to rear. Itll look better than trans to full mani after tuned. Geeze... What would cause the fluctuationg fuel pressure prolly the way i have set up then..when fixed it should even that out guessin? Quote
Scott S. Posted May 30 Posted May 30 Just a question..... I'm wondering if the length of the vacuum hose has any effect on how it "pulls open" the advance. It's a volumetric thing, a longer hose would have more suction than a shorter one. Or will a shorter hose pull faster ??? Anyone have any ideas ?? 1 Quote
jbird72 Posted May 30 Author Posted May 30 10 minutes ago, Scott S. said: Just a question..... I'm wondering if the length of the vacuum hose has any effect on how it "pulls open" the advance. It's a volumetric thing, a longer hose would have more suction than a shorter one. Or will a shorter hose pull faster ??? Anyone have any ideas ?? No clue ive ran before to carb. Im gonna try direct to manifold. It is a short hose tho...kinda a really unuser freindly design by edelbrock 1 Quote
jbird72 Posted May 30 Author Posted May 30 12 minutes ago, Scott S. said: Just a question..... I'm wondering if the length of the vacuum hose has any effect on how it "pulls open" the advance. It's a volumetric thing, a longer hose would have more suction than a shorter one. Or will a shorter hose pull faster ??? Anyone have any ideas ?? Im thinkin less distance. More vacumn. Less resistance ina shorter span kinda yu would think...like a vacumn cleaner Quote
Dtret Posted May 30 Posted May 30 No matter the length of the hose the end part only needs do much vacuum to do it job. The rest would not be accepted in the hose. Same theory with a fuel pump. Its regulated at so many psi no matter how long the line running from the tank is. 2 Quote
Scott S. Posted May 30 Posted May 30 6 minutes ago, jbird72 said: No clue ive ran before to carb. Im gonna try direct to manifold. It is a short hose tho...kinda a really unuser freindly design by edelbrock Could use a longer hose and loop it, like the brake lines at the res. Edelbrock does that so you'll stick to their products. I had lots of fun with the linkages when I did the 200r4 swap. 1 Quote
Scott S. Posted May 30 Posted May 30 6 minutes ago, jbird72 said: Im thinkin less distance. More vacumn. Less resistance ina shorter span kinda yu would think...like a vacumn cleaner Yes, but less distance can also mean that vacuum changes more abruptly too. There's no cushion to let the advance have time to change....... Just a thought, might not have that much of an effect on it. That's why I raised the question. By the way, what are you using for a cam ??? That will mess with the vacuum too..... 2 Quote
Dtret Posted May 30 Posted May 30 1 minute ago, Scott S. said: Yes, but less distance can also mean that vacuum changes more abruptly too. There's no cushion to let the advance have time to change....... Just a thought, might not have that much of an effect on it. That's why I raised the question. By the way, what are you using for a cam ??? That will mess with the vacuum too..... the cam will definitely mess with it. 2 Quote
jbird72 Posted May 30 Author Posted May 30 9 minutes ago, Scott S. said: Yes, but less distance can also mean that vacuum changes more abruptly too. There's no cushion to let the advance have time to change....... Just a thought, might not have that much of an effect on it. That's why I raised the question. By the way, what are you using for a cam ??? That will mess with the vacuum too..... Not sure i thought was around 244 246 duration .50...round 510 or higher lift...hydraulic flat tappet...i dunno i still think less air resistance more vac. But its only 8 inch difference 1 Quote
jbird72 Posted May 30 Author Posted May 30 Just now, jbird72 said: Not sure i thought was around 244 246 duration .50...round 510 or higher lift...hydraulic flat tappet...i dunno i still think less air resistance more vac. But its only 8 inch Quote
jbird72 Posted May 30 Author Posted May 30 Just now, jbird72 said: I lost all the recipts and everything i put into it 15 yrs ago...i know heads and rockers. I know installed longer pushrods so def bigger lobed than the performer rpm that was in it...i cant remember. Sucks and misplaced cam card in a move ...live and learn 1 Quote
jbird72 Posted May 30 Author Posted May 30 21 minutes ago, Scott S. said: Could use a longer hose and loop it, like the brake lines at the res. Edelbrock does that so you'll stick to their products. I had lots of fun with the linkages when I did the 200r4 swap. If doesnt work way i want ill just goto carb base fmv 1 Quote
Scott S. Posted May 30 Posted May 30 6 minutes ago, jbird72 said: Not sure i thought was around 244 246 duration .50...round 510 or higher lift...hydraulic flat tappet...i dunno i still think less air resistance more vac. But its only 8 inch difference I'm just going on a reverse theory for pressure gauges.... The longer line settles the pressure fluctuations down, and coiling the tube helps even more. Stablizes the needle. Thought it might have the same effect on vacuum lines. 1 Quote
Scott S. Posted May 30 Posted May 30 11 minutes ago, jbird72 said: Not sure i thought was around 244 246 duration .50...round 510 or higher lift...hydraulic flat tappet...i dunno i still think less air resistance more vac. But its only 8 inch difference That's enough lift to cause a change. My '86 T-Type had a similar lift/duration from the factory...... First time I took it in for an alignment, the mechanic told me it sounded like it needed a tune up, was running really rough. I just laughed, then asked if he'd every worked on one before, he hadn't. Once I let him know the specs on the cam, etc, he "sort of" grasped that that was the way it was supposed to sound. Haven't let many "shop" mechanics under my hoods since. 2 Quote
jbird72 Posted May 30 Author Posted May 30 51 minutes ago, Scott S. said: That's enough lift to cause a change. My '86 T-Type had a similar lift/duration from the factory...... First time I took it in for an alignment, the mechanic told me it sounded like it needed a tune up, was running really rough. I just laughed, then asked if he'd every worked on one before, he hadn't. Once I let him know the specs on the cam, etc, he "sort of" grasped that that was the way it was supposed to sound. Haven't let many "shop" mechanics under my hoods since. Yeah im kida a newbie compared to yall...used to wrench alot in 20s and 30s. Now north of 40. ..picked it up again and enjoying this forum and this club plus doing my own $%^^t..its rewarding. And hell lot cheeper plus love learning things 2 Quote
420ponies Posted May 30 Posted May 30 (edited) A .510" lift cam? Like 8-10" of vacuum. Flat tappet too boot,that's a rowdy cam for your sbc.🙂 Liking it!! Edited May 30 by 420ponies Spelling 1 Quote
jbird72 Posted May 30 Author Posted May 30 2 hours ago, Scott S. said: I'm just going on a reverse theory for pressure gauges.... The longer line settles the pressure fluctuations down, and coiling the tube helps even more. Stablizes the needle. Thought it might have the same effect on vacuum lines. I used the google machine fml i hate that... its 50/50. Half say better half say worse like yu said a bigger cam might make a huge diffence .. 1 Quote
jbird72 Posted May 30 Author Posted May 30 3 minutes ago, 420ponies said: A .510" lift cam? Like 8-10" of vacuum. Flap rapper too boot,that's a rowdy cam for your sbc.🙂 Liking it!! Yeah. I thought gauge was broke...its around 8 to 10. But aint timed yet 1 Quote
jbird72 Posted May 30 Author Posted May 30 Just now, jbird72 said: Yeah. I thought gauge was broke...its around 8 to 10. But aint timed yet I thk overcarbed but i thk i can rejet to compensate dunno yet Quote
420ponies Posted May 31 Posted May 31 That motor needs all of 40 degrees of timing. 3,000 rpm , balanced at zero. Your going to love it! Depending where your at ,36 just might do it. Rumpty,rump!! 1 Quote
jbird72 Posted May 31 Author Posted May 31 20 minutes ago, 420ponies said: That motor needs all of 40 degrees of timing. 3,000 rpm , balanced at zero. Your going to love it! Depending where your at ,36 just might do it. Rumpty,rump!! Yeah prez said dont be surprised if initial timing isnt high and total possibly north of 36..3000 good to know was gonna do 2500.. 1 Quote
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