Took the R/T to the track - disappointed...

[ShelGame]

OK, we took the R/T to the track Friday night and were a little bit disappointed. I expected to get into the 14's prett yeasily, but the best we could manage was 15.1 @ 90mph, even on slicks. Here's a few things we're pondering:

1) Launching - how do you guys launch the R/T's? I had a '91 Daytona with the same A568 trans. I launched it hard from about 3500rpm, just enough to rotate the tires once or twice. Tried the same in the R/T and it just bogs. Need more revs?

2) In the shutdown area, a light application of the brakes sets off the ABS. What's up with that? It's never set them off on the street.

3) Boost - the boost quickly rises to ~12psi, but then falls off as you go up in revs. Leaky BOV? Or something else?

[bradp]

Gotta get the tires spinning coming out of the hole and short shift it, don't over rev it. I used to shift my 91 at 6000rpm and stock other than Magnacor's and K&N it ran 14.5's at 96mph.

Sounds like a leaky BOV.

[Turbo3Iroc]

Good points brad. The BOV is deffinately suspect.

In launching these cars I never come out less than 5500, even when my car was close to stock. Seems as though rpm is what gets these cars out of the hole. Shift at 6k or 6200 for best ET.

The ABS light probably came on due to the different height tires. Probably best to pull the main fuse next time.

[ShelGame]

Good points brad. The BOV is deffinately suspect.

In launching these cars I never come out less than 5500, even when my car was close to stock. Seems as though rpm is what gets these cars out of the hole. Shift at 6k or 6200 for best ET.

The ABS light probably came on due to the different height tires. Probably best to pull the main fuse next time.

Ahh! I hadn't thought of that. You're right - fuse comes out next time...

[GLHSKEN]

Rob, Bone stock, my son's IROC ran a 14.88 @ 96. He was cutting high 2.2X 60's. No dump on the clutch just feathering the car out... He too expected 14's all day. Only one he got. The rest were low 15's due to learning how to launch. He missed a couple gears as well. Shifter bushings replaced since then..

[turbovanman²]

Interesting about the 5000 rpm launch.

So a 3200 rpm cap using a launch program would be too low-using street tires?

[GLHNSLHT2]

I have my 2.5 8v set to 2750rpms on street tires with a 5spd and tall 205/60's on my heavy tona.

[Turbo3Iroc]

.... 5K is a low launch these days on my car. Need to load the turbo as much as possible early on to get the thing to spool.

[Bardo]

OK, we took the R/T to the track Friday night and were a little bit disappointed. I expected to get into the 14's prett yeasily, but the best we could manage was 15.1 @ 90mph, even on slicks. Here's a few things we're pondering:

1) Launching - how do you guys launch the R/T's? I had a '91 Daytona with the same A568 trans. I launched it hard from about 3500rpm, just enough to rotate the tires once or twice. Tried the same in the R/T and it just bogs. Need more revs?

2) In the shutdown area, a light application of the brakes sets off the ABS. What's up with that? It's never set them off on the street.

3) Boost - the boost quickly rises to ~12psi, but then falls off as you go up in revs. Leaky BOV? Or something else?

HIJACK
i am having the same problem with my spirit r/t. my fastest time was a 15.6 but my mph was a 93.5 with a 2.8 60':(

when i try and leave at anything higher than 3500 rpm i smoke the clutch, and its only has 5k on it

[unluckyty]

With slicks, I launch it hard 5k +, and hope the track holds.
I have trouble launching m R/t, It will either bite or I'll smoke the slicks.
With street tires it is near impossible for me to launch.

Greg

[bradp]

I was wondering, has anyone tried airshocks on the back to keep the rear from squating?

[rx2mazda]

More info would help..........What was your 60',1/8, etc. I ran a 14.80 @ 95 in my spirit on street tires, running like crap with KR and boost issues.

[Turbo3Iroc]

There are guys that run the air shocks. I don't but I probably need to as my car squats pretty good out of the hole.

[ShelGame]

More info would help..........What was your 60',1/8, etc. I ran a 14.80 @ 95 in my spirit on street tires, running like crap with KR and boost issues.

60' was 2.5 on the street tires, 2.3's on the slicks. I was getting 2.1's on the same size MT slicks in my '91 Daytona a few years ago. Same trans, too. So, I know if should be able to knock off .2-.3 just by getting the car off the line. That would get it into the 14.8 range from where we are now. If I can get the boost to stabilize at 12psi, then I think there's another couple tenths there. After that, a 14.5 psi custom cal which should get it into the low 14's. But, that's still not fast enough for A/FS. We need to get it into the low 13's (on stock hardware!) to really be able to race.

Does anyone know what the lift of the 'stage 1' cams are for these? The ones that Delta sells? I can legally run up to .430 lift. The stock cams are only .335 or so, right?

[Turbo3Iroc]

You should be abe to get a well running stock TIII car in the low 14s without a problem. Getting one of these cars in the low 13s with out a front mount is asking quite a lot in my opinion. I never ran "all of it" boost through the stock cooler but with as inefficient as it is I wouldn't expect much better than a 13.7.

I don't know the lift on the aftermarket cams but you're pretty close on with the stock lift.

[ShelGame]

You should be abe to get a well running stock TIII car in the low 14s without a problem. Getting one of these cars in the low 13s with out a front mount is asking quite a lot in my opinion. I never ran "all of it" boost through the stock cooler but with as inefficient as it is I wouldn't expect much better than a 13.7.

I don't know the lift on the aftermarket cams but you're pretty close on with the stock lift.


Aww c'mon, seriously? I run 13.7's in my non-IC, 2.5 T1, ATX, Daytona with a Mitsu doing the breathing...

[Turbo3Iroc]

I'm assumming the R/T wont be gutted as your car is, it is also a manual where the auto is netting you a couple tenths. Maybe 13.7 was a bit high but the Spirits don't have the aero the Daytonas have either. The stock cooler is all done before the turbo is. For example I was running high 13s at 97-98 on the stock cooler at ~ 14 psi and then I put a front mount on it. No other changes netted me 13.15 at 103 or 104. After a bit of tuning I went to Cecil that fall and ran 12.77 at 105 on a 1.77 60'.

[turbovanman²]

No other changes netted me 13.15 at 103 or 104. After a bit of tuning I went to Cecil that fall and ran 12.77 at 105 on a 1.77 60'.

Wow, thats awesome to see, :hail: :hail: :clap:

[ShelGame]

I'm assumming the R/T wont be gutted as your car is, it is also a manual where the auto is netting you a couple tenths. Maybe 13.7 was a bit high but the Spirits don't have the aero the Daytonas have either. The stock cooler is all done before the turbo is. For example I was running high 13s at 97-98 on the stock cooler at ~ 14 psi and then I put a front mount on it. No other changes netted me 13.15 at 103 or 104. After a bit of tuning I went to Cecil that fall and ran 12.77 at 105 on a 1.77 60'.

It's not really gutted - still has a full interior with the sound deadening even. I have removed soem stuff, but it's far from gutted. Weighs in at ~3k with me in it. Obviously, the Spirit is heavier than that. And the Daytona does have better aero.

I would've thought the manual would be quicker just due to the better efficiecy.

That's a hell of an improvement, though. I didn't realize the stock cooler was so bad. Where's the bottleneck in it? The core or the tanks?

I guess the real question is - if an SRT-4 with only a factory 'Stage' setup (I don't know which) can run high 12's - why can't a Spirit R/T? The Spirit is lighter than the SRT-4, right? Same factory horsepower, the R/T has a better turbo, etc.

[Turbo3Iroc]

Thanks.

That is the run I am most proud about thus far. I mistyped, it was 12.74.
All those runs were under stock boost cut.

[Turbo3Iroc]

It's not really gutted - still has a full interior with the sound deadening even. I have removed soem stuff, but it's far from gutted. Weighs in at ~3k with me in it. Obviously, the Spirit is heavier than that. And the Daytona does have better aero.

I would've thought the manual would be quicker just due to the better efficiecy.

That's a hell of an improvement, though. I didn't realize the stock cooler was so bad. Where's the bottleneck in it? The core or the tanks?

I guess the real question is - if an SRT-4 with only a factory 'Stage' setup (I don't know which) can run high 12's - why can't a Spirit R/T? The Spirit is lighter than the SRT-4, right? Same factory horsepower, the R/T has a better turbo, etc.

Equal setups, an auto car will always out ET a manual car. A manual will have a higher mph.

I'm not real sure where the inefficiencies start but first it doesn't flow well and it doesn't cool well either. The location does not help it being partially blocked by the rad support.

SRT's come with a much better cooler (bigger overall, better flowing, crossflow for better cooling and front mounted) and a bigger turbo. I think they weigh about the same and were more under rated from the factory than our R/Ts.

I thought I saw you post befor that you had gutted your car. My mistake.

[turbovanman²]

It's not really gutted - still has a full interior with the sound deadening even. I have removed soem stuff, but it's far from gutted. Weighs in at ~3k with me in it. Obviously, the Spirit is heavier than that. And the Daytona does have better aero.

I would've thought the manual would be quicker just due to the better efficiecy.

That's a hell of an improvement, though. I didn't realize the stock cooler was so bad. Where's the bottleneck in it? The core or the tanks?

I guess the real question is - if an SRT-4 with only a factory 'Stage' setup (I don't know which) can run high 12's - why can't a Spirit R/T? The Spirit is lighter than the SRT-4, right? Same factory horsepower, the R/T has a better turbo, etc.

I don't think many SRT's run 12's stock or even close to 12's. Most I've seen and read all run in the mid to high 13's.

[Turbo3Iroc]

He said a factory "Stage" setup. Satge 2 which uses the stock turbo is good for well into the 12s

[turbovanman²]

He said a factory "Stage" setup. Satge 2 which uses the stock turbo is good for well into the 12s

Hahahhaaa, guess I'm taking your cue, doh!

I thought he meant stock, :o

[ShelGame]

He said a factory "Stage" setup. Satge 2 which uses the stock turbo is good for well into the 12s


Yeah, I don't really know all that much about the SRT's. He could've been running a 'Stage 9' for all I know. I do know he passes NHRA stock tech - which means stock turbo, intake, head cams, no porting, etc.

Really, all you can legally do is add fuel and boost.

[Turbo3Iroc]

They allow you to run different electronics right? That would be like rejetting a carb and adjusting the timing, no?

[Turbo3Iroc]

Stock SRT with more fuel and boost I can see getting in the 12s but I think they run too much timing up top.

[turbovanman²]

Stock SRT with more fuel and boost I can see getting in the 12s but I think they run too much timing up top.

Thats basically a stage II isn't it, just some PCM reprogramming, and a cold air intake? not up on the SRT stuff yet, lol! Stage III is the big boy one, turbo, etc, right?

[Speedeuphoria]

yeah stage 3 is the turbo upgrade ect.. package, the other 2 stages are minimal(injectors+computer) and keep the stock turbo

[CaptMoe]

yeah stage 3 is the turbo upgrade ect.. package, the other 2 stages are minimal(injectors+computer) and keep the stock turbo

I know Stage 1 is the PCM. I bought one for my '07 PT Cruiser GT. It's good for 235whp. It makes a world of difference. I never had the chance to run with an SRT on the road but i can tell you I've surprised a few Mustang GTs with that car. One of these days I'll take it to the track and see what it does but it's my wife's daily driver...;)

[Xtrempickup]

spirit is a good deal heavier than an SRT4 to my surprise

[Captain Chaos]

yeah stage 3 is the turbo upgrade ect.. package, the other 2 stages are minimal(injectors+computer) and keep the stock turbo

Can't use a stage 3 in class racing. The turbo is changed. Mine would run 13.4 @102 withs stage 1, 3" exhaust and DR's with a bad launch. 12's are possible had I used the map clamp and turned the boost up some.

[DaveSkrab]

One other thing to consider with your R/T... the 90mph trap speed seems a bit low when you compare it to all the other "stock" R/T's that post 93-96MPH. You did say that you have what appears to be a boost leak, but I wonder if your cams are centerlined?
Just a thought. Maybe Pat C. will chime in with his R/T experiences.

[BadAssPerformance]

Equal setups, an auto car will always out ET a manual car. A manual will have a higher mph.

never say never.. or always ;)

Put an auto in my Shadow an I highly doubt it would run a 12.

[Bardo]

One other thing to consider with your R/T... the 90mph trap speed seems a bit low when you compare it to all the other "stock" R/T's that post 93-96MPH. You did say that you have what appears to be a boost leak, but I wonder if your cams are centerlined?
Just a thought. Maybe Pat C. will chime in with his R/T experiences.

thats the funny thing. im going 15.4 and my mph is right around 93-95. how heavy is the srt? the spirit should be stock at 3150.

[Xtrempickup]

2003-2005 Srt4 curb weight 2970lbs. so its somewhat lighter and if its 2004+ it has an lsd from the factory. most ppl have them gutted a bit

[Turbo3Iroc]

Thats basically a stage II isn't it, just some PCM reprogramming, and a cold air intake? not up on the SRT stuff yet, lol! Stage III is the big boy one, turbo, etc, right?

I just know what I saw in that thread linked from the quote of the day thread where they said you can't run 25 psi or what ever it was on a stock cal.


never say never.. or always ;)

Put an auto in my Shadow an I highly doubt it would run a 12.

Yea I agree with the always statement but I have seen it both ways on the same car. Swapped in a auto, picked up ET and lost mph, put 5 spd back in and got it back.

What makes you think the Shodow won't run in the 12s with an auto?

[bansheenut420]

My RT with an incredibly bad blow by motor, and boost leak of some kind was trapping the same. It would spike to 13 and then fall to as much as 8psi. 15.2@91 was the best I could get with the street tires and crappy motor. I would say you have a boost leak, or some major blow by.

[glht_omni]

i took from tips kelly and rick d at sdac for launching with street tires with my red r/t. what i was told and worked for me was launching at around 3300 and feathering it out so the tires spin a little but not too much, shift into 2nd at 5100, 3rd and 4th at 5300. at sdac i was trying different launches and shifting at 6500+ trapping in 3rd at 6500+ and was pulling 14.2 @100mph.
i went back after replacing the bad motor mount and applying what they told me and i was trapping 106 @13.9 in 4th gear.

as far as your problems with the boost leak, try switching the vac lines at the wastegate solenoid and see what happens if not swap out the bov with a spare, if not get a mbc.

hows the suspension in the car? what size and brand street tires?

call me the next time you want to take it to the track and i'll take mine and we can compare and swap some parts to see.

[BadAssPerformance]

Yea I agree with the always statement but I have seen it both ways on the same car. Swapped in a auto, picked up ET and lost mph, put 5 spd back in and got it back.

What makes you think the Shodow won't run in the 12s with an auto?

It is a stock heavy car with no real traction issues... launch and hook from 5krpm... consistent 1.84 60' times, when I can find a gear its very quick... why would an auto help?

[Turbo3Iroc]

Hey Josh, glad that helped you out. Nice numbers for street tires.

JT, I'm not questioning your driving ability but an auto can shift faster than any of us so they seem to ET better but they do take more hp to turn so I think that is why they don't mph as well as a 5 speed. You can also launch with boost out of the hole.

[BadAssPerformance]

Hey Josh, glad that helped you out. Nice numbers for street tires.

JT, I'm not questioning your driving ability but an auto can shift faster than any of us so they seem to ET better but they do take more hp to turn so I think that is why they don't mph as well as a 5 speed. You can also launch with boost out of the hole.

I never said I could shift faster than an auto (damn close tho in that Shadow tho ;)) but the stick still has better gear ratios and less mechanical inefficiency (like you said) combined, so really the timing for one extra shift is offset pretty easily... Launch with boost? When you hit a stick from 5krpm and hook, you get to full boost by like the 60' mark :D

Now my Shadow is pretty damn stock and my point is that for stock vehicles, sticks can fair better. Higher HP cars? It gets exponentially harder to drive a stick the more power a car makes so the auto gets its advantages there as long as the converter and gear ratios are correct.

[Turbo3Iroc]

I think even on a stock car you might gain a tenth or 2 but yea on a faster car it will be a bigger difference. I'm in no way touting autos as all my cars are 5 speed but like I said I have seen it both ways. Was a high 11 sec car though.

[shelbyplaya]

I rev my car up to 4500rpm and hold it there. then i get hard on the gas the moment i relese the clutch!!!!! My little 22 x 8 x 15 MT slicks hold up real nice to the abuse (they love a nice toasty burn out). My best 60' is a 1.9 in a fulley loaded 87 shelby z w/ a bulit hybrid 2.5l. I'm gonna work on my 60's sunday and try to get them down into the 1.7's. Hope a dont blow another axle like I did tonight :(