Difference in IHRA/NHRA Top Fuel Rules (1 Viewer)

[Smiley]

OK, I could dig through the rulebooks and read stuff I may not understand so I am going to throw it out here for discussion..

What is the difference between IHRA and NHRA Top Fuel?

Just got back from Epping and saw..

Several 4.70s at 310+
No chutes on a 310 run and no trip into the sand
No big engine explosions
No Oildowns

YouTube - IHRA Epping Top Fuel Semi-Final

Just Great Racing..

If there are "rule" differences, why can't NHRA run a program similar and just give a great show, 1320' racing, etc..

 

[Just Paul]

It depends on who shows up too... When you only really have 6 cars run first round, and 3 of the 6 didn't make it to the finish under power, the odds of getting oil on the track go down.

Hats off to Tim Boychuk though, that was a really nice pass.

Other then the chassis rules, I think they are pretty much the same.

 

[Smiley]

It depends on who shows up too... When you only really have 6 cars run first round, and 3 of the 6 didn't make it to the finish under power, the odds of getting oil on the track go down.

Hats off to Tim Boychuk though, that was a really nice pass.

Other then the chassis rules, I think they are pretty much the same.

Thanks for the reply. So the drivetrain is pretty much identical (exception being rev limiter, etc...) So, is it safe to say that the NHRA guys hurt stuff more, and push the envelope because they have to get in and they have the seemingly unlimited funds to do so?

 

[Pink]

It depends on who shows up too... When you only really have 6 cars run first round, and 3 of the 6 didn't make it to the finish under power, the odds of getting oil on the track go down.

I wonder if it also matters that many of the IHRA TF teams just can't >afford< to hurt motors? The Laganas have always managed to do alot without much, but when you see an operation like Smax Smith's it's not a surprise that the car would not go into reverse... the wonder is it fired at all.

 

[DaveRenk]

I was thinking that IHRA does not limit the final drive gear ratio?

 

[nitro]

The rules are close, the chassis spec are different, you can still run the 1 3/8 tubing from the rear motor plate back in IHRA, as well as cast aluminum blocks, cast mag valve covers. The NHRA regulars will run 4.40's in the 1/4 at over 330 mph on a good track, The IHRA regulars will run high 4.50's to low 60's on a good track like Rockingham in the fall. Bigger budgets in the NHRA makes faster times.
IHRA regulars who are now NHRA regulars, Matt Hagen, Spencer Massey, Clay Millican, Doug Herbert, and Terry Haddock. The IHRA is a good source for future drivers.
The Smax Smith team is not a high dollar sponsor team with the owner, driver, and crew chief making the big bucks, but just a bunch of guys, with alot of heart and no budget, who races for the love of the sport, There are some professional teams that will not race for the love of the sport (meaning out of their pockets) which is a good business move.
Smith's equipment does need updating no doubt and they know it but give them credit for "living the dream" as they do work hard making it happen at every event this year, even if the equipment and performance does not show it.

Paul Weiss

 

[Toejam]

Whats gets me is I heard NHRA could NO longer get insurance for 1/4 Racing, yet IHRA Can??? I think somebody's lying somewhere....

 

[Bill]

To anyone who knows, does the IHRA have the 3.2 final drive ratio rule, and did NHRA change that when they went to 1,000 feet racing???

 

[Toejam]

To anyone who knows, does the IHRA have the 3.2 final drive ratio rule, and did NHRA change that when they went to 1,000 feet racing???

NHRA did NOT change the Gear rule, but a 2.90 gear has been needed for some time! Turning 8,500 RPM has to kill a ton of parts!

 

[Bob K.]

The 3.20 gear rule has been in place since the early 80's. At that time the "thousand foot solution" was also seriously proposed, at that time due to insurance problems. I think that's when thousand foot timers were introduced. I thought it was funny that NHRA'S "spec" deal they were playing with lately used a 3:50 (!!) gear. Think what the rpm would be with that combo at 1,320 feet!!

 

[Pink]

Smith's equipment does need updating no doubt and they know it but give them credit for "living the dream" as they do work hard making it happen at every event this year, even if the equipment and performance does not show it.

I give them all the credit in the world, and I fear that if IHRA drops TF guys like Smith will not have a place to race. My point was that when your budget is that limited you can't be leaning too hard on the motors. These guys don't have a pile of new parts and fresh bullets on hand. Guys who might only have the heads currently on the car are going to lift rather than leg out a run etc.

 

[Just Paul]

The 3.20 gear rule has been in place since the early 80's.

The first year of the 3.20 gear rule was 1990 ,the same year they took away electronic timers.

 

[Bob K.]

I did get the date wrong on the 3:20 gear. I started racing in 1961, so sometimes dates get fuzzzzzy!

 

[Smiley]

Great info by all, thanks.

Nobody seemed to mention rev limiters? Does IHRA have them?

so..
NHRA
3.20 gear
need rev limiters
BOOM!

IHRA, no gear rule, no limiters, less $$ (can't afford to hurt a motor).
1320' racing..

 

[Bullet]

NHRA - 1000' fuse

IHRA - 1320' fuse

 

[nitro]

I give them all the credit in the world, and I fear that if IHRA drops TF guys like Smith will not have a place to race. My point was that when your budget is that limited you can't be leaning too hard on the motors. These guys don't have a pile of new parts and fresh bullets on hand. Guys who might only have the heads currently on the car are going to lift rather than leg out a run etc.

David, I agree with you and it looks like IHRA will drop Top Fuel Open Completetion and go with a 4 car booked-in show.

The only rear gear you can use is a 3.20 in IHRA Top Fuel

Paul Weiss