So I took my 55 gasser out to the races first time ever, it was a blast, but man I was expecting more. Maybe some of you guys can give me some input. I have a 454 with a stock bottom end, tunnel ram 2-600 holleys, good heads,781 oval port with mild port job,2.19 valves, comp cam with 520 lift, five speed tremec trans, fenderwell headers, 30 inch piecrust slicks on back, 9" with 3:90 gears. Car felt fast until I got my time slip and only ran a best of 13.90 at 101mph. I almost cried, lol. Could it be my gearing? Car runs great on the street. Maybe I am a dreamer but I was expecting mid 12s? Any ideas would be appreciated. Thanks, Dan
Why is my fast looking car so slow?
gasserdan
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So I took my 55 gasser out to the races first time ever, it was a blast, but man I was expecting more. Maybe some of you guys can give me some input. I have a 454 with a stock bottom end, tunnel ram 2-600 holleys, good heads,781 oval port with mild port job,2.19 valves, comp cam with 520 lift, five speed tremec trans, fenderwell headers, 30 inch piecrust slicks on back, 9" with 3:90 gears. Car felt fast until I got my time slip and only ran a best of 13.90 at 101mph. I almost cried, lol. Could it be my gearing? Car runs great on the street. Maybe I am a dreamer but I was expecting mid 12s? Any ideas would be appreciated. Thanks, Dan
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Tire spin? Tire compound?
Are they old rear tires or new with latest sticky compound,
But most likely tired valve springs. What shift RPM? Big blocks heavy valve gears seams to slow quickly with every missed shift they degrade more. Switch to a conical beehive spring . Smaller diameter retainers remove lots of weight adding to RPM capabilities.
Are they old rear tires or new with latest sticky compound,
But most likely tired valve springs. What shift RPM? Big blocks heavy valve gears seams to slow quickly with every missed shift they degrade more. Switch to a conical beehive spring . Smaller diameter retainers remove lots of weight adding to RPM capabilities.
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You need to post the other interval times to see what your issues are. If your 60 ft time is equal to granny crossing the street for example, takes alot of motor to make that up... Slow at the start? Fat in the middle?
My '87 v6 Turbo Regal was running 13.3 @ 104 with an awful start. Try building boost and staying on the line with vacuum brakes.
Charlie
My '87 v6 Turbo Regal was running 13.3 @ 104 with an awful start. Try building boost and staying on the line with vacuum brakes.
Charlie
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That isn't a terrible time if it is your first attempt at drag racing. Charlie is right, you need to list intermediate times to see where you are slowing down. Keep in mind that few big block cars did much better stock in the day.
100mph on the 1/4 in most N/A cars usually gets them down to a low 13 ET.
That points out that yours is a little slow off the line. Either too much wheelspin or clutch slip,or bogging down till the revs get up. Shifting too slow through the gears will add tenths on each change. Lots of things have to be spot on to get the times down. I went out a Mopar meet a few weeks ago so my mate could race his Road Runner. It was supposed to run 11:80 by the previous owner and it only ran 14:2 ,then got down to a 12:90 just with practice. Still a full second off it's personal best. Drag racing is not always easy. Preparation and practice.
Just have fun doing it. You'll get quicker.
That points out that yours is a little slow off the line. Either too much wheelspin or clutch slip,or bogging down till the revs get up. Shifting too slow through the gears will add tenths on each change. Lots of things have to be spot on to get the times down. I went out a Mopar meet a few weeks ago so my mate could race his Road Runner. It was supposed to run 11:80 by the previous owner and it only ran 14:2 ,then got down to a 12:90 just with practice. Still a full second off it's personal best. Drag racing is not always easy. Preparation and practice.
Just have fun doing it. You'll get quicker.
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Sounds like it's your first trip to the track; 12-second times come with driver preparation too . Love angs' post about what length of track you're running on ; guess you're not the only virgin . Be safe...Bob.
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Hey Bob 13.9 isnt that slow for 1/8 mile.
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tunnel rams are for show unless your running gears and rpm's. my brides camaro dropped almost a full second when we went with the tunnel ram . this set up ran 7.0's in the 1/8 . went to the tunnel ram and it slowed down to 7:80 . takes a lot of motor to pull 1200 cfm .
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Slow?
late July 1966 , went to a drag strip 250 miles from home with a friend towing a 1966 Nova on trailer behind a 66 Street Hemi Satellite.
Decide to run the Hemi in A/SA ( None others there) with no tuneup after towing 250 miles. Car ran a 13.09 at 109+.
late July 1966 , went to a drag strip 250 miles from home with a friend towing a 1966 Nova on trailer behind a 66 Street Hemi Satellite.
Decide to run the Hemi in A/SA ( None others there) with no tuneup after towing 250 miles. Car ran a 13.09 at 109+.
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I totally agree with porchdog. But I just didnt say anything cause some dont agree and the argument will go on for days.
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The combination.
As has been stated, that is a ton of MPH for 13.90. Also stated, any tenth lost in the first 60' is a tenth added to the clock. Can you launch at WOT with those piecrusts?
You didn't mention compression ratio, fuel grade, or shift RPM. At .520" lift I don't think the cam is too big, but it needs to match perfectly with the compression ratio, which if you are running pump gas would be in the 9.5:1 range.
I think you are overcarbureted by about 20%.
CID x RPM x volumetric efficiency (Ve) = CFM
3456
Assuming no cylinder overbore, 90% Ve and 6500 RPM;
454 x 6500 x .90 ÷ 3456 = 937 CFM
A single 950 HP series carb would be my presumed optimum with your current setup, however, with more gear, more compression, more cam, more octane, more traction... you get the picture.
IMO the most economical way to improve your current ET is to run the proper fuel for the true compression, and optimize the camshaft to your compression ratio. Then there's the upper valvetrain.
:anim_25: If it was easy, everyone would be doing it.
As has been stated, that is a ton of MPH for 13.90. Also stated, any tenth lost in the first 60' is a tenth added to the clock. Can you launch at WOT with those piecrusts?
You didn't mention compression ratio, fuel grade, or shift RPM. At .520" lift I don't think the cam is too big, but it needs to match perfectly with the compression ratio, which if you are running pump gas would be in the 9.5:1 range.
I think you are overcarbureted by about 20%.
CID x RPM x volumetric efficiency (Ve) = CFM
3456
Assuming no cylinder overbore, 90% Ve and 6500 RPM;
454 x 6500 x .90 ÷ 3456 = 937 CFM
A single 950 HP series carb would be my presumed optimum with your current setup, however, with more gear, more compression, more cam, more octane, more traction... you get the picture.
IMO the most economical way to improve your current ET is to run the proper fuel for the true compression, and optimize the camshaft to your compression ratio. Then there's the upper valvetrain.
:anim_25: If it was easy, everyone would be doing it.
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You probably just need to paint flames on the car, that's good for 0.5 second.
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Nope, on th Moroso calculator it is good for 12.98.
I agree with you.
My thought is you need some work everywhere.
Launch rpm, tires, and suspension will almost certainly improve your 60' times. (Though right now there's not much to go on without times and other data. But it can almost certainly be improved on.)
Your tunnel ram doesn't match your camshaft, rear gear, and probably your heads.
I would work on the 60' first. If you don't make that better, it will mask other improvements.
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You say the bottom end is pretty much stock so I would guess you are not turning too many RPMs because of that. If that's so the tunnel ram is killing you. Get a tamer intake and one good carb that will flow 700 or 800 cfms
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