Cruz and TF dragster headers

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Nitro Member
#1



If you walked by Cruz Pedregon's pit during the weekend and thought his engine sounded and looked a little weird during the pre-race warm-up, you were not mistaken. Crew chief Aaron Brooks bolted on a pair of Top Fuel headers for the warmup – but, obviously, not the run -- but there’s a method to his madness.

Brooks, who has a deep background in Top Fuel, has noticed that the EGT (exhaust gas temperature readings) at idle that he was used to seeing on his computer screen varied wildly in Funny Car compared to the tightly-grouped readings he was used to seeing on his dragsters. Because crew chiefs will utilize these EGTs as a tuning aid, perhaps to calm an overly hot cylinder, they’re a crucial piece of the puzzle.

“Because Funny Car headers are so long and have a lot more backpressure, the idle temperatures are really scattered,” he said. “We’ve been struggling with dropped cylinders so I thought this was one way I could get a better handle of what the actual idle temperatures are.”

The Snap-on Tools team, clinging to the tenth and final spot in the Funny Car Countdown field, believes it finally has found its footing, with a series of good outings after a tough early-season go.

“I told Cruz it would probably take 90 runs to get this combination where we want it from scratch,” he said. “Friday was run No. 90, so here we are. We’ve had some good events – Englishtown, Topeka – but screwed up in eliminations and I really feel like we could have won in Denver. Lately it’s dropped cylinders that is killing us, even though we’re still making good seven-cylinder runs. Hopefully we’re getting closer to getting it figured out.”
https://www.facebook.com/CruzPedreg...414457679332/1572919582728805/?type=3&theater
 

Sandman

Nitro Member
#4
Remember Tim Grose's Datsun-bodied flopper? It had something kinda similar where the headers exited at the base of the windshield area. Not sure if there were any plusses or minuses with it though.
 

Cliff

Nitro Member
#7
Grose may not have been the only one running that style of header. Seem to remember more than one car tried that. Was also thinking of the original Wedge dragster of Don Prudhomme. They ran the headers thru the top of the wedge, then changed to F/C style headers. Don't remember why they did that, but the car ran better with the F/C headers. There was a lot of experimentation in T/F around 1971, with running headers pointing straight up; supposed to give more down force. They went back to regular headers after awhile. Interesting to me how F/C has made great strides with the style of header they now run. Don't seem to see much experimentation in T/F header design, not like F/C, anyway.
 

Nunz

Nitro Member
#8
I think the TF headers have been laid back for awhile, but I could be wrong. I also remember Cory Mac driving, maybe a Tuttle car, in the past year or so, with a kind of shorter FC header. But it may have been only a qualifying experiment.
 
#9
Why not point them down and forward so that they exit the body just behind the front wheels.
A forward distance move that looks about 10 -12''.
This would provide a 'lever' to help keep the front end down. Then they can angle them back and in.
Why hasn't anyone thought of this and tried it out?

Just saying.
 

Cliff

Nitro Member
#10
Why not point them down and forward so that they exit the body just behind the front wheels.
A forward distance move that looks about 10 -12''.
This would provide a 'lever' to help keep the front end down. Then they can angle them back and in.
Why hasn't anyone thought of this and tried it out?

Just saying.
You can see a version of this design in some of the Pro Mod, 10 wide, etc. They run the header in front of the front wheels. Looks strange but it works. I think most of the cars that do that are turbo cars.
 
#13
Why not point them down and forward so that they exit the body just behind the front wheels.
A forward distance move that looks about 10 -12''.
This would provide a 'lever' to help keep the front end down. Then they can angle them back and in.
Why hasn't anyone thought of this and tried it out?

Just saying.

4c4d.jpg
 
#15
Grose may not have been the only one running that style of header. Seem to remember more than one car tried that. Was also thinking of the original Wedge dragster of Don Prudhomme. They ran the headers thru the top of the wedge, then changed to F/C style headers. Don't remember why they did that, but the car ran better with the F/C headers. There was a lot of experimentation in T/F around 1971, with running headers pointing straight up; supposed to give more down force. They went back to regular headers after awhile. Interesting to me how F/C has made great strides with the style of header they now run. Don't seem to see much experimentation in T/F header design, not like F/C, anyway.
I remember Prudhomme changing his wedge to the funny car style headers so that he could hinge the wedge and swivel up ala Funny Car style for quicker maintenance.
 

Cliff

Nitro Member
#17
Too bad The Wedge was too heavy. I was at OCIR one night, & Snake raced Rick Ramsey in the Keeling & Clayton front engine car. Both ran 6.43 ET, which tied the world record at that point, & Ramsey won on a hole shot. I think Snake ran 234 on that pass, which was a good MPH for T/F then.