So summer is rapidly coming to a close, and I have failed to move the gas tank out of the cab, purchase a set of drag radials, and hit the drag strip. Looks like I am not going to make it this year.:ball: And my friend in Colorado is hording my G-Tech meter--not really safe to do 1/4 blasts on the street with this beast any way.:Brow: And my newer computer will not run my Dyno 2000 and Drag 2000 software. Still, am I really curious what my truck with the 455 in it might run. Of the 2 nearest 1/4 mile tracks to me, one is at about 1700' asl (might need more than 91 octane pump gas to run there o No and the other about 4800' asl. I would run 275/60R-15 drag radials, and the converter stalls right at 1600 rpm before the brakes just can't hold it any more. I think all the rest of the important specs are in my signature. What do you guys think it would run? It's probably not as fast as I think it is, but it sure is a blast to drive! :3gears:
I had a 455 Buick powered Chevy 1/2 ton short box that would run low 14s with less engine than you have. Same gear ratio without posi. Got it to hook pretty good with an air bag on the right. It was a 70 engine with a factory stg2 cam and headers, nothing else. You could possibly make high 13s Bob H.
Thanks for the replies guys! Bench racing is better than no racing at all:Brow: May be I will get my act together and get it out to a track next year.
Should be able to get into the 13's. A little more converter would help. My guess would be a 2200 rpm converter would really perk up your 60 fts. A 9.5 inch built by someone good (I love my Edge) drives great on the street and makes the hit off the bottom so much better. It is hard to spend too much money on a converter. You get what you pay for.
You're kidding of course? You guys have more straight stretches in between the Wall Drug signs than in all of Pennsylvania. You could do 50 1/4 mile blasts just driving out to Wall. When we were out there 10 years ago on the Interstate coming into RC my wife told me to slow down because the T-tops on my TA made noise above 120 mph. Get on the line to your "friend" and get the G-Tech back. Out there mid 14's. East coast into the 13's. If the wind blows right maybe a little better. I agree if you have good traction get a little bit of a converter in there. It will help with high altitude sluggishness. For mild use I'm a big proponent of regular brand name off the shelf units when you're in the 2000-2500 rpm range. A typical 11-12" unit should do.
Well, all right then... G-Tech should be on it's way back to me shortly. Stand by for some time slips.:beer How accurate are those G-Techs? I like the converter advice. My original goal after some drag strip passes was to install 3.08 gears and head to Bonneville to take a crack at the 130 mph club. Doubt I have the power to put the truck there with it's blunt aerodynamics, and if I did have the power, it would be difficult to get it to the salt with the front/rear weight ratio. Any way, how much stall can I get away with with the higher gears?
I would swap to a more street friendly gear in the rear end, regardless of how it effects the quarter mile time... At least it would get better mileage and be faster on the highway. Also do not be too quick to change out the converter, it does not really sound like you know the actual RPM that the converter will flash to. Footbraking will not tell you the flash RPM of the converter, which is really what the word "stall" refers to when people talk about converters... To me, the important thing to consider when you are deciding if a converter is too loose or too tight is: The RPM that the engine goes to when you floor the engine from a dead stop... If the engine goes to 3200 RPM almost instantly when you leave the line then you have a roughly 3200 stall converter with your combo... The more torque an engine makes the higher the actual RPM flash compared to the advertised rating. The less torque the engine makes the lower the RPM will flash up to if using the same converter.... if you plan to keep the gears then avoid a high stall converter as it will only make your highway RPMs higher and trans temps higher... That said, a high quality converter can give the best of both worlds.... Myself, I have been spoiled with overdrive trans and lockup torque converters so I refuse to use a non overdrive or non lockup converter... Once you use one you will never want to go back..... Leave the 3.73 gear, swap in a stock 4L80E, use a 4500 stall lockup converter, and enjoy low RPM on the highway, 100% lockup when you want it and still have a converter that flashes right up when you floor the gas pedal off the line.
Don't know what the flash rpm of the converter is. With the tires on the truck now (215/75R-15), if you floor it from a stop, the tires will instantly light up and if you stay in it, they will keep spinning until about half way through 2nd gear--can't even tell if it shifted.:laugh: Loads of fun, but... I know I need a serious rubber upgrade back there.ou: :idea2:Next time I have some weight in the back hauling something, I will mat it and see what it flashes too. Yes, an overdrive would be nice. I have a 4L80E in my 1991 Four Winds motor home, and I love that, and if it ever gets wrecked...:Brow:. But an overdrive was not in the budget when I did this build, and won't be, unfortunately, for quite some time. I know all about a good converter and a crappy one. My friend that has my G-Tech has a 1969 Dodge Charger. Years ago we put a B&M Holeshot converter (11" 2500 rpm rated stall) in it (440, 727 torqueflite, 3.55:1 gears). That thing felt like mush. When cruising if you put your foot it in a bit, the engine speed would increase about 500 rpm and we felt no change in vehicle speed. I guess it just absorbed the extra torque and turned it into heat. We replaced that with--I think it was--an A-1 converter that was 10" and stalled about 3000 rpm, but cruising if you added throttle, yes, the rpm's would increase a few hundred, but the car would accelerate nicely. Worlds apart as far as efficiency and driveability. I don't think that A-1 is in business any more or I would look to them for a converter.
Oh happy day! A chance to argue with Sean. 4500 rpm stall! Those of us that have big blocks don't need that stuff. :laugh: What do you want us to do hit the flash and shift at the same time? Or did you stick a SBC in there when we were not looking? I run a big solid lifter cam and still have a tight 2800 rpm stall converter. The idea is going from a roll at 2000 rpm might give me a chance to hook up as the converter hits the stall. Need to get the drag radials back on for a hope in he## of that working ou: I did Sean's test last week and hit 6000 rpm. It was hit throttle, shift light comes on.... ---------- Post added at 07:14 PM ---------- Previous post was at 07:08 PM ---------- I see Steve got the lesson on converters already. A lot of the big name stuff is now junk unless you can get into their race departments. The efficiency and drivability of a good 9.5 is hard to beat. Mine is so nice to cruise but still has a wicked hit on the throttle. Not buying it about 11 and 12 inch converters. Ran a modified D5 for a while and lost 15% on the top end.
Finally got the answer to what it will run... well, sort of... Made it to the last Friday night street legal drags at the Sturgis Dragway October 9th and it was a bit disappointing. On the first time trial run, the truck had some fuel starvation issues and laid down at the top of 1st and 2nd gear but recovered each time, and only ran 9.79 seconds @ 73.2 mph with a 60 foot time of 2.26 seconds (1/8 mile track). I red lighted to boot, and spun a bit off the line. I believe the truck was vapor locking a bit as I idled it along in the staging lanes with no airflow through the engine compartment. Second run was better. I opened the hood and my wife Melinda and my Dad pushed me through the staging lanes with the engine off so things could cool down. The motor maybe had a slight stumble at the top of second but much better. I still red lighted and spun even more as the 60 foot time dropped to 2.29 seconds but it ran a 9.25 @ 78.4 mph. If I use the Wallace Racing calculator to convert 1/8 mile stats to 1/4 mile stats, I get 14.45 @ 97.2. That is less than I had hoped for. But then if I use another calculator to convert that from 3400 feet elevation to sea level (car magazines do it all the time so I can too) I get 13.7 seconds @103 mph. Air temp for the runs was right at 60*, but I don't know what the barometer was at. Also this track runs slightly uphill, especially at the start. But after the second run, it was all over. I had been in denial all after noon, because my stomach had just not been feeling right since lunch. Couldnt fight it any more and went over to the fence and barfed. I called it quits and we all went home before any actual racing happened. Maybe next year. Melinda was just a fantastic supporter through all this, keeping me supplied with sprite and came over to the fence with a rag to clean my self up if necessary. She also had water on hand and gum in case I needed any. Then she drove me home in the truck. Dad was a good supporter too. He decided that the "worse" the car sounded at idle, the faster it went down the trackgreat observation. On the bright side, at least the truck did not break. Some things I could do to make the truck run better: First of all I need to run less pressure in the drag radials. I had 26 psi in them, but I should have dropped that about 10 more psi. Also did not do any burnouts. Shifting at a bit higher rpm might help some. I just left the shifter in drive and let the transmission shift itself at 5200 rpm. 5500 rpm shifts should improve times? It needs more torque converter, as the stock one in there now is 13 in diameter and stalls about 1600 rpm foot braking it. An 11 unit with about 2500 rpm would get the truck moving much better and improve the 60 foot times greatly, but that might just make it spin more? I think I am pretty solid on the tune, but could try a little more timing as I was running 30* total. I think it is also a bit rich overall. Would like to try adding cold air induction. And mostly I need to relocate the fuel tank out of the cab and into the rear and use 1/2 fuel line and add an electric pusher fuel pump, or maybe just adding a return line would do the trick. Any way more weight on the rear tires would improve traction, and be safer(?). Here are links to youtube videos of the 2 runs: https://youtu.be/2Qjb_XG2uN0 https://youtu.be/ykDk8Zs9zS8
