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Hi Vet Rider....I think this is the first time I have heard of the problem happening with a half tank. Just curious at what part of the track did it happen and did you datalog back when you had the Hellcat? I've never owned a Hellcat but interested in fuel delivery system. A motor going lean is the best way I know of to have to replace it!!! Thanks
Yeah always logging my car. It happened on the street and at the track. Right after launch at the track and close to WOT in 3rd on the street. Fuel pressure would drop to 19psi at the rail then the car would push inj duty cycle to the moon and open the bypass and vent all the boost. Then the car would fall on its face. All logged. Then filled up and it was fine same night same road same temps...
 
Hi Linda can you give us some of the logic and parameters (ex. how he used the 60', mid track, and trap ETs and MPH numbers) our husband used and maybe the Wallace Racing Calculator(s) that helped him arrive at his conclusion? The HP had to have a considerable impact and I'm wondering where the breakpoints are to go from 18 to 17 to 15 might be. This trial and error method gets expensive unless you have friends that can loan their tire/wheel combo for a few passes. Thanks
Really the difference with wheel size is just going to affect your sidewall. So if you have a 28" tall tire on a 15" wheel, you have a lot more sidewall, versus a 28" on an 18" wheel. More sidewall=more gooder for drag racing. A MT 305R 18 is 29" tall and a 305R-17 is only 28" tall. 315R 17 is 29.4. This is why people run 15" wheels if possible.


Chris, also there are three approaches people take to launching these cars
1) stomp on it
2) roll into it
3) stomp halfway and then roll into it the rest of the way

First order of business is a good tire. A 30" tire is a big old tire, but a taller tire gets you a bigger foot print, so that is good and not like you don't have enough torque off the line with that insanely deep first gear the car has.

I have run hoosiers from time to time. Good tires.

I agree that the nitto are limited depending on the HP of the car. Personally, I'd get a race tire if you are going to get anything else, rather than wasting time trying to get a Nitto street tire or something similar to work. There's a reason why so many people run MT R's, or a Hoosier drag radial. Though I did think the MT SS worked pretty good when I just had a tune on my car, and I think it would work even better on a really well-prepped track.
 
could have been a 1320?
Yea you may be right...not totally familiar w/ all the model/trim levels. I checked out the Dodge Build & Price web and found the 1320 option which was only on the narrow body Scat Pack. The option indicated that wheel was a 20x9.5 and a 275/40 tire but that's not necessarily conclusive. Did a search and found an article stating the 1320 was coming back for 2021. The article said the tire was Nexen SUR4G Drag Spec 275/40R20 and checked that the wheel was a 20" which it was. Maybe someone w/ a 1320 can respond. FYI- called Nitto again to get an update and it was even worse. They indicated that the NT05R tires regardless of size are no longer manufactured and that all their stock has been sent to Dodge or NTB (I think that who they said and bet Dodge got all the 315/40R18s). I should have asked them when they stopped manufacturing since that will be the newest age wise that anyone could have (buy and new car and get a tire that's 2-3-years old or maybe older). They recommended the 555RII for the rear and the 555G2s for the front. I did have some hope that I would be able to keep the 05R for street use but not anymore. I hear the 555RIIs are OK but don't put the G2s on the rear. Definitely won't be doing any burnouts in Mexico just for fun. Wonder what the Demon's are using now? They also told me the minimum recommended pressure for the track (drag strip) was 15-psig for those that track the tire.
 
Yeah always logging my car. It happened on the street and at the track. Right after launch at the track and close to WOT in 3rd on the street. Fuel pressure would drop to 19psi at the rail then the car would push inj duty cycle to the moon and open the bypass and vent all the boost. Then the car would fall on its face. All logged. Then filled up and it was fine same night same road same temps...
Thanks...datalogging is essential and your log tells the story...exactly what you would expect to happen. Was there any knock or did the computer catch it in time? Don't take the time to go back and look if you don't remember. Learned something new...Thanks appreciate your response.
 
Discussion starter · #66 ·
Really the difference with wheel size is just going to affect your sidewall. So if you have a 28" tall tire on a 15" wheel, you have a lot more sidewall, versus a 28" on an 18" wheel. More sidewall=more gooder for drag racing. A MT 305R 18 is 29" tall and a 305R-17 is only 28" tall. 315R 17 is 29.4. This is why people run 15" wheels if possible.


Chris, also there are three approaches people take to launching these cars
1) stomp on it
2) roll into it
3) stomp halfway and then roll into it the rest of the way

First order of business is a good tire. A 30" tire is a big old tire, but a taller tire gets you a bigger foot print, so that is good and not like you don't have enough torque off the line with that insanely deep first gear the car has.

I have run hoosiers from time to time. Good tires.

I agree that the nitto are limited depending on the HP of the car. Personally, I'd get a race tire if you are going to get anything else, rather than wasting time trying to get a Nitto street tire or something similar to work. There's a reason why so many people run MT R's, or a Hoosier drag radial. Though I did think the MT SS worked pretty good when I just had a tune on my car, and I think it would work even better on a really well-prepped track.
Thank you. Just booked a family vacation so we’ll see if there’s any crumbs left for racing
 
Hi Sick Too So I'm thinking that a 1.77 60' is good for a normally asperated 394??? It's interesting to note that he had the identical tire and size as is on factory Demons and Super Stocks (might also be on the Jailbreak). Did he have the wheel also? You can't buy that size from Nitto or at least they are not on their web site and when I called them they told me to use the 555RIIs. The Parts Mgr at the dealer tells me he can't get them either. He says his suppliers are out of stock. Didn't even find any on Ebay. So your competitor must have gotten them from someone who owned one of these models that changed them out for something else. He was lucky to get them. I only have 700 miles on my SS and in my opinion up to 500HP the Nitto NT05R are a great tire, quiet, and probably as good as the MT ET Street SS and the ET Street Rs on the street (pick up too much gravel etc). I've only had mine loose traction once (trying to conserve since getting a replacement might be a issue) when I had to goose-it pulling out into traffic, it got a little sideways in a 4-wheel drift. In a straight line rolling acceleration (in 500 HP) I can feel the tire slip just ever so slightly then bite, the car reaps forward and takes off. Never experience that before but never been on a true wrinkley slick and way better than the 305/35-20 Pirelli's on the Redeye. At 800HP they can't handle the job at the track let alone the street w/ one exception; apparently a track that is prepared my Mass Traction (I think that their name...a professional group that goes around preping tracks for big events) can do the job. These tires are known to break differential housing if you have the power. That's why I have a the Drag Pack from my previous Redeye for the SS at the track. I wouldn't get on the track in a SS or Redeye w/ this tire unless I cut the HP to 500 and did some testing to ease into a full launch.
It had the regular old 10 spoke hellcat(?) wheels. Dunno what it was. My naturally aspirated stock 392 sixties in the 1.6’s. Stock as in stock motor, I lowered the back of it and got rid of the rear camber. According to this forum I slowed it down in doing so and would be quicker if I raised it back up lol. I don’t think so. 3580 mt 22 psi on 18x10.5 wheel. Last night was the first time I ran it at the track. Didn’t play w tire pressure cuz was testing launch rpm. 330’ in the 4’s so it will dip into 11’s. Good baseline. 7.6 1/8 - it wants boost : )
 
Hi Linda can you give us some of the logic and parameters (ex. how he used the 60', mid track, and trap ETs and MPH numbers) our husband used and maybe the Wallace Racing Calculator(s) that helped him arrive at his conclusion? The HP had to have a considerable impact and I'm wondering where the breakpoints are to go from 18 to 17 to 15 might be. This trial and error method gets expensive unless you have friends that can loan their tire/wheel combo for a few passes. Thanks
@Top Cat :(rip:(
It seems to me the faster the car goes the wheel size gets smaller.
On My Husbands Challenger Known as "Top Cat" has the 15 inch conversion for the 15 inch wheels

So I have 309 gears and of course the I had 262's but I run high 9's
The guys I know running 17's do so with both 309 and also the 262 gears, they are running lower 9's heading for the 8's
My husband's Challenger runs the 15's I have to check the gear size, but there is also a DSS 9inch rear installed and the gears are not standard. His Hellcat runs 8's.

I hope this is helpful and answers your question. I can get more info from my friends from the track.


Many members have done all the testing for us through the years and there are answers of good combinations posted through out the layers of posts.

Linda :)
 
As In Like I use MT ET Rs in 305 45 18?

Here are the Tires sizes that are seen most at the track with Josh@HHP
He sells the popular sizes that are being used by many for the different Trims
As his customer I am there with many other customers and we all track test parts and tuning.
HHP's website could be used as an index. Most everything has a pretty good description.

 
Ignore. Nothing worthwhile to add so I deleted it ha ha

Need to get to the track!!! Cabin fever is kicking in.
 
  • Like
Reactions: Chris jimenez
All I was saying is if you go to the Mickey site and look at the R’s you will see ya can’t really compare a 3572 and a 3576. (The two 17’s she was referring to). Look at the advertised specs : )

Tire Car Wheel Land vehicle Vehicle


Donnies Nova w a drag radial last night



Tire Wheel Car Vehicle Automotive tire


Those are 15x12 wheels for his bias ply slicks. Kinda narrow for a 10.5 pro drag radial but oh well. Still ran in the 4’s almost 150 turned wayyyy down
 
Discussion starter · #75 ·
As In Like I use MT ET Rs in 305 45 18?

Here are the Tires sizes that are seen most at the track with Josh@HHP
He sells the popular sizes that are being used by many for the different Trims
As his customer I am there with many other customers and we all track test parts and tuning.
HHP's website could be used as an index. Most everything has a pretty good description.

Thanks
 
It had the regular old 10 spoke hellcat(?) wheels. Dunno what it was. My naturally aspirated stock 392 sixties in the 1.6’s. Stock as in stock motor, I lowered the back of it and got rid of the rear camber. According to this forum I slowed it down in doing so and would be quicker if I raised it back up lol. I don’t think so. 3580 mt 22 psi on 18x10.5 wheel. Last night was the first time I ran it at the track. Didn’t play w tire pressure cuz was testing launch rpm. 330’ in the 4’s so it will dip into 11’s. Good baseline. 7.6 1/8 - it wants boost : )
I'm with you on the boost! That's the answer to going quick. But it sounds like your Challenger can hold it's own against any NA of similar specs. A 1.6 60' is really good! And a 7.6 in the 1/8 will beat most 500HPs at least in my area where DA during race season is typically 1500 to 3000. The final track day last year in early Nov, the DA was 300 at noon but 950 by 4:30 that afternoon. Lot of PBs that morning including me, took better than 0.2 sec off the ET. I'm not familiar w/ the info on this forum (just joined) but when you say you got rid of the rear camber was that by replacing the stock trailing and control arms w/ adjustable arms and setting the camber to 0.0 degrees? (or did you set it a little positive so that when you get in it goes to 0.0 for max tire contact patch). Lowering the rear should have moved center of gravity rearward putting more weight on the rear tires. What's the logic used to say it slowed the car down????
 
@Top Cat :(rip:(
It seems to me the faster the car goes the wheel size gets smaller.
On My Husbands Challenger Known as "Top Cat" has the 15 inch conversion for the 15 inch wheels

So I have 309 gears and of course the I had 262's but I run high 9's
The guys I know running 17's do so with both 309 and also the 262 gears, they are running lower 9's heading for the 8's
My husband's Challenger runs the 15's I have to check the gear size, but there is also a DSS 9inch rear installed and the gears are not standard. His Hellcat runs 8's.

I hope this is helpful and answers your question. I can get more info from my friends from the track.


Many members have done all the testing for us through the years and there are answers of good combinations posted through out the layers of posts.

Linda :)
Thanks Linda...it won't be necessary. I think you said it all the faster the car the smaller the wheel. i.e. the more torque and HP the smaller the wheel. When you start looking at the 8's you'll need a 15" wheel. 18s are good for 10s. And 17s are a good all around size. Thanks w/ this info I have rethought going to a 15" setup at least for a while.
 
It was good air and decent track. Bar press was a lil low but so was the humidity. Da went from 1700 to 1000 for my last pass

My car had 1.5° of negative rear camber stock. I bought the cheap adjustable bmr links nib from a member. People here install them and then try to take their car to a road corse and bend em lol. Work perfect for what I want. No I didn’t get all anal w it and put any positive camber. Not yet : )
 
It was good air and decent track. Bar press was a lil low but so was the humidity. Da went from 1700 to 1000 for my last pass

My car had 1.5° of negative rear camber stock. I bought the cheap adjustable bmr links nib from a member. People here install them and then try to take their car to a road corse and bend em lol. Work perfect for what I want. No I didn’t get all anal w it and put any positive camber. Not yet : )
I'm with you on the BMR...had the on car adjustable rear lower trailing arms in the Redeye and will do both trailing arms and control arm on the SS. Could definitely tell the difference from the stock setup on the Redeye.
 
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