I mainly wanted to post that pic but I do see straps on street cars at shows and events that are not alky's (the cars, I don't know about the owners).
Just like wheelie bars; if it's obvious the car doesn't need it.........it's obvious it's obviously................
I do. Or I did. Car hasn’t moved in 4 years, but when it did, I was required by the ECTA that it have straps, but not current certification, which saves a lot of money. Went 205 just like that.
I personally only run restraints or a bag on my street driven vehicle or Drag engine unless I am 7,000 engine Rpm's & over 12 pounds of boost with static compression of 11 to 12 to 1, My last full race was close to 70% OD @ 9,700 engine rpms Alky . Here are Rules ,,, NHRA Supercharger Restraint Rules Overview of Restraint Requirements The NHRA has implemented specific rules regarding supercharger restraints to enhance safety in drag racing. These rules are particularly relevant for cl***es like Pro Mod and Top Sportsman. Key Restraint Specifications CL*** RESTRAINT SYSTEM REQUIREMENT ADDITIONAL NOTES Top Sportsman Minimum six-point (SFI Spec 16.1) or seven-point (SFI Spec 16.5) Must be updated every two years from the date of manufacture. Top Dragster Same as Top Sportsman All belts in open-bodied front-engine supercharged methanol-burning vehicles must have a fire-resistant covering. Implementation Date These new restraint rules will take effect on July 1, 2025. This change aligns the requirements for Top Sportsman and Top Dragster with existing rules for other NHRA cl***es, ensuring a higher standard of safety across the board. Importance of Compliance Adhering to these new rules is crucial for racers to maintain eligibility in compe***ions. The updated restraint systems are designed to provide better protection and comfort for drivers, ultimately enhancing their racing experience.
Big difference between Required and or Needed for safety reasons and having the pieces on in hope of impressing the mouth breathers. Case in point on the wheelie bars, I doubt many of us would falt Finnegan if he finally showed up at a drag strip with wheelie bars on the 55. Some of the spectators might get upset because they aren't going to get that wheelie shot they were hoping for but the guys who run in the other lane will think it was a great idea.
Nitro and alcohol need them, gas doesn't. I did run them on my 41 but when I made up new valve covers the straps interfered with the breathers, both physically and visually. I did move the straps to a spare setup on display in the house. As far as wheelie bars, how does one just look at a car and know it won't pull the wheels ???
@Mr48chev Finnegan's 55 would be Faster with bar's But He likes dragging bumper , Bars also a tunning option one tire speed & other , back in Pre 70's Most did not know what Bars could be used for , Most where used just to keep vehicle off the bumper and fenders. @swade41 68 motion Camaro's where known to Carrie the wheels 1st & 2nd on street on street with tires of time , Back in mid 60's family friend drove A Sedan 4 speed DD & school onto 70s He could leave with tires in air 12 inches & when really showing off drag fenders after tearing them up a few times he bobbed them . Here quite a few street cars could carry the tires before 1975 , Mags @ time only showed very little what was going on around the US or other countries.
On a street application, if you have a corrrectly sprung pop off valve, the chance of lifting the blower lessens. What you will do is probably bend the rotors and ruin it. With some of today's tech and the alum studs, it might come lose. On the old v belt drives, the belt would slip and lessen the damage.
When I was trying to get the preliminary fire up of the flathead I had a few backfires under the blower, got to see those plates in action. What a mess they made of my polished intake! I ran a toothed belt rather than V belts mainly because everyone around here was running the multiple V belts and I don't like being like other people.
Thanks! I hope to get it back out there one day. I hear ECTA is going to run 1/2 mile events at Maxton again.
I’m thinking about restraints in my FED. 40’s vintage I6, vane supercharger running ****-through, alky injected. There are only six 1/4” bolts holding the manifold to the head… and a large volume of fuel/air mix upstream. The blower manufacturer from the 60’s notes that banging the blower in this setup can be “of nuclear proportions” It runs two relief valves, but they may not be enough. cheers, Harv