Corzette Posted June 5, 2004 Share Posted June 5, 2004 Well not good. I had the same MPH about as with the DUAL PLANE but lost 3/10ths due to the dog off the line comparitively. My average MPH gain from the 1/8th to the 1/4 was about 25MPH gain with the single plane vs 23 MPH gain with the dual plane. However, the loss of power from the line ate that right up. I was running 2.04s and 2.07s off the line....unsat! I do have the 3.54 rear still in though. Surely the 411s will make a difference. Im thinking about putting the dual plane back in. 12.4s are much more acceptable once you have already been there. The wierd thing is I never lost one single race. I beat uo an old school camaro 68 or 69 that was a little built. A bug with wheelie bars and pretty damn fast and several mustangs. I have the clips if someone wants to see them... I guess the 383 makes better use of the Victor Jr. At least in my case it was not a good swap. 411s may be a different story. I will know next month as I have a 411 R200 coming.....Comments anyone??? Terry Quote Link to comment Share on other sites More sharing options...
mas28O Posted June 5, 2004 Share Posted June 5, 2004 I never had good luck with the single plane manifold with the 350 motors. My old 383 loved the single plane manifold. Are you sure you want to use the 4.11 gears. If I had 4.11's I would run out of gear and my car would run slower. Right now in 3rd I am running 6300 rpm in the 1/4. The 4.11 might help the 350 but the 383 will not need them. Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted June 6, 2004 Share Posted June 6, 2004 Terry, It's hard to believe you lost time by switching intakes When you stall it up on the line what rpm's are you at? I have friends who have 350 sbc's and run both single and duals and most like the singles. My 383 loves the single plane! I can leave the line at idle with no stall and still turn 1.70's for 60 ft. I also am running a low 2400-2600 dayco crappy 12" converter. I have no bog or hesitation. Mike Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted June 6, 2004 Share Posted June 6, 2004 generally a single plane intake won,t give you possitive results untill YOUR AVERAGE RPM stays at or above about 5000 rpm and you don,t fall lower than about 3500rpm at any time in the run. I think youll see the vic juniors performance improve once the 4.11 rear gears are installed simply because the average rpms the engine sees will increase about 17% single plane intakes RARELY work well if the cams duration is under about 235@.050 lift either, let me put it another way...if your not spinning the engine over 6500rpm for a good part of the track,and / or useing 383 or greater displacement a QUALITY dual plane intake is likely the better choice. don,t forget that what goes in needs to go out, effective header/exhaust scavaging is mandatory your bog or lost torque off the line is more than likely the result of lower port air speeds, that fill the cylinders less efficiently, changing the gears will help, as the AVERAGE RPM and port speed will increase with the increased engine rpms BTW IVE NEVER yet seen the vic JR intake give quite as good of results as the SUPER VIC intake gives IF THE ENGINES TRUELY BUILT TO RUN 4500-7500rpm and the displacement is 383-427cid, minimum http://www.newcovenant.com/speedcrafter/calculators/intake.htm http://victorylibrary.com/mopar/intake-tech-c.htm http://www.ramairbox.com/ http://www.rbracing-rsr.com/runnertorquecalc.html Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted June 6, 2004 Share Posted June 6, 2004 .., BTW IVE NEVER yet seen the vic JR intake give quite as good of results as the SUPER VIC intake gives IF THE ENGINES TRUELY BUILT TO RUN 4500-7500rpm and the displacement is 383-427cid, minimum .., I herrrrd dat! If your main concern is a daily driver then you need the dual...and with your engine you still need to up your rear diff w/3.7-3.9's. If your main concern is maximum WOT performance then keep the single and up your gearing in the 3.9 to 4.11's to compliment your engine's peak power rpms in the 4500-6500 rpm range as grumpy suggested. Maximum port efficiency is the goal. You cant obtain this maximum airflow velocity in your ports, which leads to maximum cylinder filling, if your airflow is stalling due to off the line bogging due to mismatched gearing. If you want your engine to reach its full race potential then you have to swap those gears for something which parallels the car's intended level of performance. Right now you have an engine that wants to roar while the gearing in your differential is mismatched to your engine and causes the car to think it is still a daily driver. You drivetrain is confused. It doesnt know if it is a race car or a grocery getter. Unfortunately slumbering port pressures at low rpm's are the victim..and this compromises your engine's full potential. Swap them gears and your tiger will roar once again! QUESTION: What is your engine's peak rpm and at what rpm do you shift to a higher gear when racing? What size rear tires are you running? What transmission gears are you running? Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
Corzette Posted June 6, 2004 Author Share Posted June 6, 2004 My cam is from 2200-5800 RPMS Peak ocurring at 6100 and torque at 4500. My rear is currently 354 but have 411s coming. My tranny is a 700R4. My stall is 2800 but only can go to about 1900 before the tires slip. My dual is rated to 6000 RPM however. Even with the 411s I wont exceed 6000 in third. I now run the traps at about 5200 or so at 111. My tires are right at 26 inches. Nitto 275 50 15s. I shift at 6000 RPMS. Terry Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted June 6, 2004 Share Posted June 6, 2004 *NOTE: Your 383 will definately like that single plane intake...as you pointed out in your first post. As far as your 355 is concerned-here are the parameters you have given. 1) My cam is from 2200-5800 RPMS Peak ocurring at 6100 and torque at 4500. 2) My rear is currently 3.54 but have 411s coming. 3) My tranny is a 700R4. My stall is 2800 but only can go to about 1900 before the tires slip. 4) My dual is rated to 6000 RPM however. 5) Even with the 411s I wont exceed 6000 in third. 6) I now run the traps at about 5200 or so at 111. 7) My tires are right at 26 inches. Nitto 275 50 15s. 8) I shift at 6000 RPMS. Just off the top of my head I can see the obvious-you're hitting the traps well below your cam and (Dual) Intake's maximum potential: which is at 6000rpms. Yes I know-I am stating the obvious. Yet you are running a Single...not a dual intake. The Vic Jr's are rated at peak rpm's in the 7000-8000rpm range: your 5200rpm trap speed and or point at which you shift...6000rpms, is no where near 7000rpm or 8000rpm range. You will either need to swap gears to those 4.11's to improve airflow velocity withing your engine's ports, or you need to go back to your dual intake manifold. Still, even if you go back to your dual your gearing is still wrong for that 282 cam. You need at the very least 3.9 diff gears to take full advantage of your cam. 4.11's with your 700R4 trans, and 25.83" tires will net you 6000rpms...providing you can maintain traction from the start. The problem with this is that your mph will only be 112 (?) with no wiggle room to go faster if you are not going to exceed 6000rpm. I personally think, and its easy for me to say this because it's not my car; that 3.9 diff gears will suit you better if you went back to your dual intake. This leaves you with 118mph wiggle room at your max 6000rpms. If you wish to keep your single then you will need to rev your engine up to the 7000-8000rpm range to take full advantage of your single intake, otherwise why bother having it if you are not willing to rev your engine to the intake's mfg's suggested peak rpm? 2nd question; if you are going to keep the single intake and decide to rev it to 7000-8000rpm can your engine handle continual 7k revs without busting something? I think you would like 3.9 diff gears more than 4.11's...just my .02c's worth. Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
Corzette Posted June 7, 2004 Author Share Posted June 7, 2004 Kevin, thanks for the info. Well Ill keep my 411s but I may go to the Nitto 275 60 15s vice the 50s. Question is will they fit? I have and inch and a half clearance now with the inner fender still there. I can cut it out as well to make more room if needed. This tire is 27.99. That would yield me a 121 MPH potential I believe. I currently dont have the power to exceed that so it would give me alot of growing room and great launches would it not? The stroker will go in later this year probably when it gets a little cooler however..... Terry Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted June 7, 2004 Share Posted June 7, 2004 Terry, Kevin makes some excellents. Here is my piece of advice. Whatever combo you end up with, change one thing at a time and give yourself more than 1 trip to the track to see how it works. In most cases it will take several passes with a combo to find out if the problem is a specific component not working or it was just a bad day at the track. PATIENCE! Quote Link to comment Share on other sites More sharing options...
Corzette Posted June 7, 2004 Author Share Posted June 7, 2004 Scotty I agree. Im gonna wait and go again and try the 411s with the single plane etc. You have run bigger tires before...will 28 inch tires fit in the wells? (275 60 15s?)? Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted June 7, 2004 Share Posted June 7, 2004 Traction may be a problem with those 4.11's. You might be able to get away with it with your 355 yet your 383 may be a different story. Good luck and as if I have to say it - let us know how it turns out. Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted June 7, 2004 Share Posted June 7, 2004 We appear to have about the same size flare and the biggest tire I ran with the Nissan IRS was a 275/50-15 on 15x8 with a 5.5 BS. Biggest tire I ran period was a 27x11.5x15 QTP and those suckers were wide but with the C4 IRS I did not have to worry about clearance with the strut/spring perch. 28" is a tall trie for a Z and will probably give it that jacked up look. The key to fitment would be the backspacing and clearance with the spring perch. A 28" tire with a 4.11 would be about the same as a 26" tire with a 3.90 (more like 3.82) but the 60% 275 will have a bigger contact patch for more traction. However, keep in mind that the 700R4 has a 3.06 1st and when combined with a 4.11 will make for a busy 1st gear. The often forgotten key with an automatic is the convertor stall and the correct stall will put the engine in the sweet spot right off the line which is key for quick a 60'. Quote Link to comment Share on other sites More sharing options...
Pyro Posted June 10, 2004 Share Posted June 10, 2004 Your 1/4 mile et looks pretty good with the mph. However, your MPH seems low for a 383 with a pretty big cam When I first did my V8 swap I ran 12.8's at 110. It was a 350, 11:1 cr, 292H comp cam w/roller rockers, GM T5 trans, r200 w/3.90 gear, holley 750 vac, performer rpm intake, block huggers, 2.5 inch single exhaust, and 165cc GM "fuelie, double hump" heads with 64cc combustion chambers and 2.02/1.6 valves. Later, I installed 200cc iron eagle heads with 64cc chambers, full length hooker headers, and dual exhaust and picked up 10 mph and dropped a full second (11.8's at 120). Then installed a set of MT drag slicks (26x8.5x15) and a 175 shot of N20 and ran 10.7's at 135 mph in the 1/4 mile and 6.9@110 in the 1/8 mile. 135 mph was at the very top of 4th gear! I made all these gains using the same engine, cam, intake, carb, diff, and trans. So what i'm trying to say is....... You didn't mention what heads and what kind of exhaust you are using but I bet you need to make improvments in the head and in the exhaust area. If you already have good heads and exhaust then you have a problem somewhere else because your not making enough MPH. FYI, the Performer RPM airgap (dual plane) intake kicks butt and works great on just about every application. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted June 10, 2004 Share Posted June 10, 2004 The often forgotten key with an automatic is the convertor stall and the correct stall will put the engine in the sweet spot right off the line which is key for quick a 60'. Forgive me if this seems like a "dumb" question but where exactly is the sweet spot. Is it where the peak TQ is or where the peak HP is? Guy Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted June 10, 2004 Share Posted June 10, 2004 My 1971 240Z with an 11 to 1 383/700r4 combo went 11.60 at 118 with a dual plane Weiand stealth intake. That same combo except a intake change to the Victor jr. single plane went 11.30 at 121. No other changes were made. The car can go faster, I do not stall it up at all due to not wanting to break anything far from home with no trailer and a crappy stall converter. With a Vigilante 3500 rpm 9.5" converter and some good tires the car could go 10's. The cam is not big for a 383. 236/242 duration and 553/540 lift with 110 lobe seperation. cam is a Comp cams extreme energy hyd. roller cam. I shift at 5800-6000 rpm's. Mike Quote Link to comment Share on other sites More sharing options...
Corzette Posted June 11, 2004 Author Share Posted June 11, 2004 Pyro, ugh...I dont have a 383 yet, just a 350. Im running 12.4s at 112 with the dual plane. Im running an AFR dual plane match ported to the AFR 190 heads, block huggers and 750DP. The single plane slowed me down by 3 tenths but kept the same MPH. maybe you have me mixed up with someone else. CZ Quote Link to comment Share on other sites More sharing options...
Corzette Posted June 11, 2004 Author Share Posted June 11, 2004 Mike, isnt your 71Z about 300 lbs lighter than my 73? Do you remember what you were running with the 350 and the 276 cam? Terry Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted June 11, 2004 Share Posted June 11, 2004 Terry, I ran 12.20 at 114 for a best with that combo. 350 sbc xr276 extreme energy comp cam with 10.3 to 1 compression and the same Weiand stealth dual plane intake. Mike Quote Link to comment Share on other sites More sharing options...
Pyro Posted June 11, 2004 Share Posted June 11, 2004 Yes, 114 mph is getting there! And the cam you used was pretty mild. So, I think that combo worked pretty well. When you changed to the bigger cam and single plane intake is when you had the problems. Maybe the valve springs aren't strong enough or the fuel pump isn't keeping up? Or a different tune on the carb could help? You should pick up only 1 or 2 mph with a 4.11 gear swap. Most of the improvement with the gear swap will be in the et. Maybe as much as 0.5 seconds. I noticed you are using 190 cc afr heads in your label. Those are the best heads out there! With a set-up like that, your car should be runing 118 to 120 in the 1/4 mile. In any case, I would use the performer rpm intake. In this month issue of hot rod mag. they tested 6 manifolds and the performer rpm airgap made more power than all the others tested. What are you using for exhaust? Quote Link to comment Share on other sites More sharing options...
Guest zfan Posted June 11, 2004 Share Posted June 11, 2004 Terry, Actually going by your signature you say your car is 2365 lbs. I have weighed my car on the scales at Ennis, Texas Motorplex. My car with me in it weighs 2750 with me in it. No I am not a FAT ASS. .185 lbs soaking wet . My 1971 must just be a PIG Mike Quote Link to comment Share on other sites More sharing options...
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