Just warmed Buick up while Im warming Victory up. At warmed idle the vacuum thingy gives positive resistance to the air flaps opening Thats all I have time for this morning...sunny day and the long and winding road is calling. Time for some 2 wheel torque and HP
Are you backing into the water box with the street radials, then doing your burn out? With any treaded tire, you would be better off doing a dry burnout and avoiding the water. The water can kick up into your wheel wells and on launch drip back down on the tires and you'll lose traction - even a 100' (30 m) out from the start. Nando.
First of all, forget about short shifting. Any good stock 455 should be shifted around 5000 rpm. With that cam I'd say shifting around 53-5500 would be about best. Peak HP is probably around 52-5300. It absolutely makes no sense and I don't care if the Buick is a "torque" engine, whatever that means. Think about it, a particular(not necessarily yours) engine makes 300 peak HP at 5000 rpm and it makes 275 HP(probably even less) at 4000 rpm. How does shifting at 4000 rpm get you anywhere faster? You just gave up at least 25 HP. Maybe somebody can explain how that works? Maybe you have a diesel? If you have an engine that runs best short shifted that radically something is wrong with it, ignition, fuel delivery, or valve train. Short shifting is meant for engines that are pushing the limits of the rpm range of said engine and even then it is rarely more that a few hundred rpm way up there it the rpm range. I'm pretty sure the '70 Stage 1 engines came with a bit higher stall speed converters than non-Stage 1 converters and I'd bet money that an original factory T400 converter for a "big" car probably came with an even slightly lower stall speed than for a GS model. Just something to ponder when trying to match the '70 Stage 1 ET/MPH. We used to toss in a factory 12" T350 converter out of the junkyard for a stall increase over the large 13" T400 converter. Also, just because TA says the factory converter is acceptable with that cam it doesn't mean it is optimum. A generic 12" 2000 stall converter would make a huge difference off the line compared to a factory 13" unit. That bit of info was just an FYI since you want to keep your current converter. Check the distributer for a missing bushing under the centrifugal weights. The factory bushing was rubber and it is probably gone. Aftermarket recurve kits usually come with a small brass bushing to replace it. That is probably why you have too much distributer timing and too little initial. If it is in there then the slot the bushing moves in will need to be brazed up. I believe the Stage 1 engine was set up for 10* initial and you'd like it up near 15* so you're way behind on low end torque. In a pinch you could probably run only one light spring in the distributer and keep total timing to 34*. That would allow the timing to fly to the 34* probably by 2000 or maybe lower. Maybe not the best but something you can easily do by popping the dist. cap and rotor off. You can always put the second spring back in when you leave the track. In my experience the secondary pulloff canister should take two seconds to slowly extend out after you push it in with your finger. Quickly remove your finger and then count 1001, 1002 and it should be out. Much faster than that and it could bog(especially with a tight converter). Much slower and then you are giving up precious time when the carb secondaries are at WOT. Some generic canisters pop out way too quick and cause a bog and then they try to get away from that by turning the windup tighter. Slowing down the secondary flapper that way is just wrong. I seriously doubt even stock fuel pump would be taxed by mid 13's unless there is some blockage in the tank or elsewhere so that should not be a problem. As mentioned other people have gotten their car to go fast with stock converters and highway gears but you have to get everything else right and consistent. When you think about it what you have is basically a stock 455 with somewhere around 9.5:1 compression, stock '70 heads(They are not Stage 1 valves are they?), probably highway gears(3.08's? FIND OUT!), and a tight 13" converter. What you do have going for you is a bigger than a Stage 1 cam which should add HP and headers which should also add HP. By the way what exhaust are you running behind the headers?(I may have missed that.) Looking at that I'd say you have mid 13 second potential and maybe around 105 mph in good air. You're limited by head airflow at this time so get everything else working right. Other things to try. I probably missed it , what intake? Are the heat crossover passages blocked at the head so the intake is not getting too hot? Find out where the cam is set at and consider advancing it another 2-4* or at least make sure it is advanced 4*. Add a 1" 4-hole spacer under the carb. Both will add some low end torque to get that tight converter/lousy gear/lazy cam off the line. For now take the air cleaner housing off the engine at the track. It may be hindering you a little. You can always compare on/off at a later date once you get a bunch of runs under you belt. Make sure you shallow stage every time for lowest ET(Look it up on the internet.) As mentioned elsewhere I believe you will have to power brake hard at the line with the tight converter to get it off the line. Probably should be able to get to 15-1600 rpm sitting there without dragging the car out of the shallow stage or across the starting line. Get weather information of the track when you are there, elevation, temp, pressure, humidity. The last three vary from day to day and will absolutely make a difference in performance and can explain changes in performance, good or bad. Assuming you are serious you will keep all the junk out of the trunk and no mate in the passenger seat or kangaroo or dingo or something else. Of course that extra weight is fine if you are not serious about getting a low ET. But at that point why would you ask for help?
Theres a pic of the convertor in the build albums. Also a pic with comparison of the Stage 1 TS heads to what I presume are stock looking at valve sizes. Paperwork states 3.42 rear gears, Ill check next time back is up in the air and I have time to mark it. Exhaust is the stainless 4-1 headers into bolt up collectors tapering back to twin 2 1/2" all the way to the back. H balance pipe about 6" back from front uni . Redback glasspacks , ( not cherry bomb type but look like a normal muffler from outside) Ive ID'd them by part number stickers still on them. Reciepts show it shipped outta US with Hush Thrush, I suspect they were changed to quieter Redbacks to not draw attention of law. They can noise and polltion test here now! I used to run Flowmaster Series 40 on my 351 Ford and they sounded great and performed. The exhaust now sounds good without being excessive and when I sink the boot it sounds great! No doubt Flowmaster 40s would sound and flow better . Just changing my brake fluid right now , gravity bleeding which takes time, bit over 1.5hrs now and just about to button up the last bleeder.
I really don't know what to think of that "Bog" that far out. UNLESS the Secondary's are NOT opening until that point. One thing to try is to hold the secondary air flap closed & see what happens. Gotta keep the process using the KISS principal BEFORE & doing the basics. You have to start someplace. Tom T.
and its not every time...an inconsistent 'bog'! its like thump!..total loss of power and motorvation for half a second...feels longer at the time....then off we go again! see the smoke that comes out the pipes as she clears?....
according to the Motor Trend stripper test the Stage 1 trans is set up to shift at 6000rpm! Tach redlines at 5500! How hard will a 455 safely rev?....when I hit neutral instead of drive it went off the dial! I got a good 60lbs oil pressure revved, and 20psi at idle
wasnt hot though, Australias not really a searing hot dustbowl with kangaroos everywhere.......errr well actually a lot of it is at the moment! drought, bushfires, no rain for the farmers for ages....Where I am on the coast aint too bad but and its cold at night, Id guess around 60F that evening or colder.
How much fuel was in the tank? Fuel slosh can be a nagging issue, and will do what has been described, gets up and goes then falls on its face then jumps up and goes again. I let the trans shift itself on the 1/2 then I click third. Set the governor for 52 to 5500 and let it do the work.
possible...but had a good half a tankful...and didnt do it on the later runs...I just watched it repeatedly from .32 on the vid and it really dies in the arse for a few seconds...note theres wisps of smoke from the exhaust as she leaves the line, then a decent cloud as the fire lights again...I think too much fuel putting the fire out
If it noses over completely, then you may have a fuel pressure problem as Tommy suggested. The only way to know is to monitor fuel pressure. When you run a car down the track, it reveals any weakness the car has. Everything has to be right. Running lean at WOT is one of the worst things at the track because as you go lean, the engine can detonate, and that will eventually hurt it. When a Q-jet bogs, it doesn't completely stop pulling, it just bogs down a bit. When you run out of fuel, it noses over and stops pulling completely. I doubt you have too much fuel, but if you like, you can check which secondary rods you have installed, they are EASY to get out. You can see the secondary rods on top of the air valves. They hook onto a hanger that is secured by one screw. Remove the screw (don't drop it into the carburetor), and the hanger lifts off taking the rods out of the secondary jets. The rods have a 2 letter code on them. That will tell you how rich or lean they are. Another thing to look at is that the secondary rods are lifting out of the jets. As the air valves rotate open, there is a plastic cam that rotates and lifts the rods up. You can easily see that by just opening the air valves by hand. That plastic cam can break. Check it. I would not race the car until you straighten this out. You may need to rig up a temporary fuel pressure gauge and tape it to the windshield. See what happens to the fuel pressure does as you go WOT.
IMO there is way too much thinking about that big bog run. If it does it once who knows what was going on? If it does it consistently then you have a problem. That seems to me to be a heat problem. Maybe the OP is one of those guys that sits in the lane letting the car "warm up" because the temp gauge said it was "only" 190*? If I'm in the lanes and the temp gauge is right about 160* when I'm pulling into the burnout box that is about where I like it. That is of course after the engine oil has been thoroughly been heated up by driving it and getting it up above that temp. The engine water temp can cool below 160* at that point and the oil temp will still be above that temp. If it was his first run after driving it to the track and there was no appreciable cool down then there could have been fuel percolation. I never heard an answer about the heat crossover in the heads that goes to the intake/carb. An easy way to check is if the intake is discolored on either side of the carb down where the intake meets the head. Aluminum or painted cast iron will discolor there if it has too much heat. Unless you have to have the smoothest idle or drive in the coldest temps there is no need for that much heat. All the holes blocked off with a single 1/4" hole near the choke is all you need. If 60* temps is the lowest temp you see normally then you don't even need that. I'd say once you get down to actually driving the car in 40* temps would it become important for choke operation and intake heating. Another possibility is the float is set a bit high and on that particular run it pushed fuel past the needle/seat and dumped gas in the engine. I would think that would cause the problem more consistently though. As noticed the smoke at the starting line and then at the top of first indicate fuel dumping into the intake and I'd bet on the carb percolating from too much heat on that run. The later runs came after some cool down either in the pits or sitting in the lanes, hopefully with the car turned off. I'm pretty sure you cannot over fuel an engine with a Q-Jet to cause smoke if using factory jets and secondary metering rods. Maybe a little too lean but not rich enough to cause noteworthy smoke. Maybe if the secondary rod tips were cut off exposing the full secondary orifice but as Larry suggested the rods are easy to check but I don't see how it would only do it one time and then not again. Mechanical devices that go bad don't fix themselves. If you have too much preload on the lifters an engine will almost shutdown because of valve float if it is way too much and maybe on that particular run you hit an unexpectedly high rpm? A free wheeling engine such as when you went into neutral at the shift won't act the same as one under a load. Just a possibility. I'd get the preload checked no matter what to see where you stand. Some hydraulic lifter cams are notorious for having what some would call lifter crash at a certain rpm which is really aggravated by too much preload and the engine just seems to hold back a bit as it gets to that rpm or a mild case of case valve float. You never mentioned what rockers/pushrods you have. Hopefully either the pushrods are the correct length or are adjustable or the rockers are adjustable. I've run mechanical pumps that dropped the pressure down to 2 lbs. running low 13's and adding an electric pump made no noticeable difference in performance even though it now had 7 lbs. pressure. I'm sure it was close to the tipping point where it would shut off from lack of fuel but at that point it was not a problem. As long as the carb has positive pressure the engine still gets gas. I like the fuel slosh idea but the OP said he had a lot of gas in the tank and it would only have gotten worse on each successive run as the fuel level lowered. That video sure looked like it except if the car ran out of gas it would not have been smoking which to me means excessive fuel. They didn't need 6000 rpm on a stock Stage 1 back in the day and you certainly don't need it now. That was old school small block Chevy thinking. 5500-5700 is safe and should be all you need for that cam. I saw elsewhere you had a problem watching the tach and racing. If that is the case get a tach in a position where you can watch it or get a bigger one. Practice out on the street with it shifting from 2-3 at 5500. The 2-3 shift is easier to make because you have time to think about it. Then move on to practice the 1-2 shift. It is a lot to think about at the track so practice on the street and you won't have to think about it as much down the dragstrip. I like the idea of setting up the trans to shift automatically 1-2 at the correct rpm but that would require your getting the governor out and probably multiple trys to hit the right rpm and if you can't get a dizzy recurved then the governor is a step up in complexity although it is not really hard to do. Not to be-labor the point but I have to wonder about the builder of the car who decided that while the engine was out it wasn't good time to think about some kind of mild converter. What's up with that? Glasspack type mufflers are fine as long as the core tubing is the same as the inlet/outlet diameter. Some cheap models use the same size core for everything. Usually a 2" core but then they toss 2.5" in/out hookups on it. Those mufflers you mention seem like a good brand when I looked at their website. The Hush Thrush mufflers are what you call tri-flow mufflers and we would normally call turbo mufflers so I don't know how they would be considered loud but whatever. What exact muffler p/n did you install? Ford 9" rears have 3.00, 3.25, 350 gears available so you may be better geared than the way this thread has appeared to go so you may be a little better position to hit your stated goals. I would do a quick compression check on all cylinders to see what you are dealing with. Hopefully they all come out reasonable to confirm a well sealed engine. Heck, even if some of the cylinders are out of tolerance you can always make adjustment to your expectations. Unless some of the cylinders are wayyy down compare to others or the engine is smoking all of the time you can still race it. I did like the OP's assessment in that if the factory had run of the mill timing and jetting and other such stuff and the majority of GS455's normally ran 14's then why can't he do it without worrying? You better believe that the Stage 1 that ran 13.38 was a super tuned setup and super tuning your setup is what you are trying to do. Assuming you have no major mechanical problems I say go at it. Heck, you're doing what the majority of the folks on this board(and probably most boards of other makes) have NOT done, which is run your car at the dragstrip so that is a plus. The OP is actually projecting realistic easily achievable performance goals for his car. He has run into some problems and I believe once everything is taken into account(Including actual racing conditions(weather), race weight, and driver experience.) he'll hit his goals. It does go to show that just because your car has A/B/C modifications or XXX HP it doesn't necessarily mean you will run 13/12/11/10's when the car actually hits the track. Shoulda', coulda', woulda'. Many have run into that reality before.
Thanks Larry and No Lift Im only just partway into NoLifts post and just went downstairs to check the heat on the inlet and yeah sure enough heres a pic...still reading but its long post and its 115am here. So this could be causing me problems? Whats the fix? As you say and from experience I agree wholeheartedly a car can perform great on the street and break down on the strip...I went through years of it with my Ford and various 'tuners' and 'mechanics' as well as a dyno 'operator' till Terry sorted it out properly so yeah I know the story only too well.
Ok thanks NoLift Im just finished your interesting and comprehensive post..Ill try to answer by reading on my laptop and answering here on my phone First up the Redback glasspacks part no. F728MN Also Larry Im not about to delve into the Rochester Ill leave that to the expert , Terry . Now the heat on the inlet manifold, do we have to remove the inlet to block holes? I dont think it revved hard enough for valve float. Pushrods and rockers are unknown at this stage. So Id guess stock. I had an Autometer monster tach on my Ford and got rid of it cos it was way too bright, I dont like bright lights in the cab. And it was wired into the dashlight rheostat but still way too bright for my liking. Dizzy will be recurved to perfection soon and the carb set up too. Ill show this thread to Terry for reference too. As to the engine builder and the converter well I just have no idea except that he fitted a TH200 OD trans and thats how the car was shipped, with the TH400 matching nos trans in the trunk. The Tasmanian owner had the TH400 tricked up and refitted, Ill email him and find out the specifics. I didnt install the mufflers, one of the owners before me did, either the original importer in Tassie or the guy in Sydney that he sold to and I bought 3 years after he bought it. I just presume it was cos of noise he fitted the Redbacks. My Buick dont have a 9inch Ford rear...My Ford did have tho with 3.25 gears, originally 3.0 then I tried 3.50 before settling on 3.25 for good all rounder. Anyway thats the Ford and its gone.. Im running the Buick 3.42 rear end. Ill leave it there and await your reply and hopefully later in the week Terry can work some magic on the carb and dissy and whatever else he deems neccessary to do.
what your seeing is from the heat crossovers in the heads, common, word is pulling the intake and plugging those holes are worth 20+ hp
Whoooo!...really? Was wondering when someone would come back on that. Thanks. So Id need another intake gasket, ****...and Ive just done the coolant
About those heat riser holes, If Im pulling the inlet manifold itd make sense to source a nice dual plane Edelbrock or similar inlet dont you think? Theyre probably a bit thin on the ground Downunder but Ill do some research . Lose some originality but hey most folks here dont know what it is anyway! What do you think?
