13TX

Let me say first that I'm relatively new to the third gen message boards and while I've had a few quick Camaros, this is my first 3rd gen.

I have a black 85 sport coupe, full interior, 350 SBC .040 over, all forged rotating assembly, balanced & blueprinted, 11:1 compression ratio with a 294 comp solid flat tappet cam, Pro comp aluminum heads with 210cc runners, Victor Jr, Holley 750 dp, built TH350 transmission with a red neck 10" 3500 stall converter, posi with 3.73 gears. Ran 12.2s the only time I took it to the track.

So I took it out to the local cruise spot and there was a guy there with a new 5.0/6 speed with only a X-pipe and a cat back exhaust. He would only run from a roll so we lined them up and went 20-120. He pulled me by a car. We ran it back, exact same result. I'm super disappointed with that and I just wanna know everyones thoughts. What recourse do I have? I know those things are quick and the fact that it was a roll race favored him, but in my mind my car should have definitely taken that 5.0. Thoughts?

RedLeader289

iTrader: (2)

What was the distance?

The 2014 5.0 makes 420 hp, 0-60 in about 4.5 seconds.

It's going to be a quick car and like you already said-is favored in the roll. With 3 more gears than you (2 of them overdrive) he's always going to either A) outrun you or B) pass you when you're pegging your RPMs at the top of 3rd.

Not trying to be harsh, I too have a built TH350 and that limits stuff a bit (which is why I eventually plan to do the manual swap).

You could convince him to go from a stop at the track. That way there is a set distance and your gears are in your favor.

13TX

Just to clarify, we ran from a 20 roll to 120, which is slightly above what I trap in a quarter mile. No set distance. We ran fender to fender thru my 1st gear, then my fender to his door thru my 2nd gear. When I hit 3rd he started to creep away more steadily... Eventually to 1 car length at 120mph, then we shut down.

I know alot of what you said was right, but that gives me little/no consolation. There has been alot of money, time, blood, sweat & tears poured into this car. If it can't beat a near stock coyote Mustang from a slow roll, that has to classify as an epic failure in my humble opinion. SMH

Z28FAST1

Those 5.0's run strong. Swap in an LS and be done with it

13TX

I've definitely thought about it, though that's more of an undertaking than I'd prefer. I'd like to beat new school technology with straight up old school stuff, but who knew it would be so freaking difficult? I guess I'll go with a solid roller cam swap, bigger better AFR heads, an AFR Titan intake + DaVinci carb and Yank SS3600 converter FIRST and see where I am when the dust settles.

no new tires

THEN, add a Procharger or nitrous...or both.

end-

13TX

^^^ True. Already have a NX Trinity plate system in the works.

Z28FAST1

Solid roller for a street car? How much are the AFR's after porting?

You can buy a junkyard 6.0 for $500-$800(LQ4), slap in an off-the shelf cam and make 420-450rwhp easily. If you want the old school look and feel you can even run a carb set up and make more peak power.

At that power level a coyote with mild bolt-ons will not touch you!

RedLeader289

iTrader: (2)

Yeah, I read that. Another thing to consider though is that starting from a roll isn't an exact science, one of you could start a fraction of a second before the other one and make a big difference. I'm personally a big fan of cars that are quick on all motor. What exhaust are you running?

Where he's getting you is in the gearing. You have the weight and hp on your side. (not saying that you have more, because you don't, but you have more in a lighter package)

I believe that the rear end gears in the 2014 GTs (unless he got a premium option) are 3.55's.

If you start from a dig then you should be able to make enough ground up in the first little bit that he would just be catching you when you shut down.

With a high-stall converter and a 3-speed you basically built your car to be a 0-120 car, so if you want to race in anything other than that to it's fullest potential then the tranny is your biggest drawback.

13TX

I'm running 1.75" full length headers and 3" 2 chamber 40 series Flowmasters.

I like your perspective and I agree with what you're saying again. My problem is gearing and frictional losses from the old school automatic transmission... I get it. That is why I'm upgrading to a Yank converter... Less slippage. I'm seriously considering upgrading to a 4 speed auto as well.

All that being said, I feel that roll racing is about 2 things... Power and gearing. No matter what I do, short of a T56 swap he's gonna have me in the gearing department. So I have to make more power. Whatever it takes... Solid roller, bigger heads, better intake + carb. WHATEVER IT TAKES. I'm only gonna get 1 chance to run this race back and I've got to make it count

RedLeader289

iTrader: (2)

Tim Taylor from Home Improvement just popped in my head when I read "more power" (manly grunting laugh).

Good luck with what you decide to do!

redneckjoe

can you kinda ride the brakes a little before the start to get the RPMs up higher?

IDK, i never did any roll racing. could be worth doing some practice launchs?

seems to me that you should beat him. car tuned and running strong?

how about tires and traction? any issues?

Fast355

iTrader: (2)

Reduce your weight. Every 100 lbs is like adding 10 hp!!! You are not losing as much as you think on the older 3spd, the newer 4spds eat more power. The only one that would hold up to your engine is a 4L80E and it is a heavy, massive, power hungry 4spd that does not have the greatest gear ratios. When you hit OD the car will fall on its face. If you really want to fly on the freeway, you need something like the Germans did and still do in some cars. A moderate final drive (~3.00:1) and a 4-5 speed transmission that is relatively close ratio (~3.5:1 1st and 1:1 5th) and NO Overdrive (Richmond 5spd comes to mind).

You could always convert to a solid or hydraulic roller cam and free up some extra power.

Finally ditch the flowmasters, they are JUNK and do not flow well. Go with a straight through muffler like a magnaflow, much less restriction.

13TX

No traction issues- car hooks really well with the ET Streets and this thing is running SUPER STRONG engine wise. I haven't tried any practice launches from a slow roll... Not a bad idea. May be worth looking into.

13TX

Ok so the 4 speed overdrive option is out then. Gutting the car to shed 2-300 pounds is definitely an option as is the solid roller cam, but I'm not ditching the Slowmasters Lol. I'm married to those things man... They sound AMAZING on this car.

no new tires

-fixed

redneckjoe

flowmasters sound cool, but, i agree they are robbing power from you. they're probably one of the worst flowing muffs out there. do some reaearch. not being a smart-azz at all. maybe some cut-outs would help? theres actually some kinda formula for HP to exhaust and muffler flow rate. the exhaust can really hold you back.

sounds like a tight motor.

i agree with losing some weight. a glass hood is a good start.

13TX

No offense taken at all to anything you guys have said.

I hear you guys on the Flowmasters... I may look into some Magnaflows or Borla race mufflers or a cut out to bypass the 'problem' entirely.

I already have a fiberglass hood.

Upon driving my car after this roll racing event that I talked about, I noticed my transmission slipping. Was it slipping when I ran this guy? Probably... Hard to say. I'd be inclined to say it was and the transmission has likely been 'on the way out' for a little while and I just failed to notice it. Regardless, I have the best performance transmission man in my area rebuilding my TH350 and a TCI Super Street Fighter converter going in as well (off of his firm recommendation). I'm going to throw some new roller rocker arms on it (just because I don't like the ones that are on it- seem cheap) and an AFR Titon TXR intake with a DaVinci 790cfm 4150 carb. Just because I want to. Should be on in the next month.... I'm gonna run this race back as soon as I do and I'll let y'all know what happens. Assuming I win this time, I'm gonna throw a NX Trinity kit on it and go after bigger game. Hopefully will be able to run some high 10s/low 11s with that combo on it. Thank you guys for all your input.

brandonj92fireb

Holy cow, im surprised your car isn't running faster than that. I have a 355 wiseco kr1 pistons, rods and crank. Shp heads 180 heads that I did some work on them with a dual plane intake. 10-1, It does have a hydraulic roller four pattern cam from comp that has power from 3000-7000 with a ultra light weight lifter set. Th-400, s60 with 3.54 and my car has gotten really close to 11.5, it was like 11.61 @120.

NJ SPEEDER

With that cam and only a 3.73 gear I would have to wonder if you are getting the most out of your powerband. What was your trap speed when you ran it at the track?

If you want to optimize track performance you can use a one of the many gear calculators on the interwebs and enter your gearing and tire size to figure out what RPM you are look at for your current trap speed. The common train of though is that you want a gear that will turn the shift light on a little before you cross the finish line. This should translatre to using your entire powerband in every gear.

-Tim

13TX

I know man... Its super discouraging. But upon further research, I think its the ProComp heads that are holding me back. From everything I have gathered talking to people and reviewing internet message boards, they are GARBAGE. When you add in the the troubles I've had getting the valvetrain geometry right on this motor and its subpar performance, I'd say it is certain. As a matter of fact, when I talked to a tech guy from Clay Smith about a solid roller, he said he wouldn't even sell me one til I swapped the heads out because he's seen the studs just rip out of the bosses and the bosses break at their base due to stress on the rocker arm from high lift + high spring pressure. Obviously when this happened, it was catastrophic... Took out all kinds of stuff when it happened in the case he told me about. So it looks like I'm about to have to go in for some AFR 210s as well... My wife is gonna be pissed. Oh well. But that in conjunction with the other mods I mentioned + more gear should get me where I want to be.

13TX

Tim, the trap speed was 107. It was kind of a dog on the big end. Don't remember what my rpms were passing thru the traps.

Fast 383

iTrader: (2)

I don't post here much anymore. Mainly because I switched over to Mustangs a few years back. I've had a few since than but recently I picked up a 2013 Mustang GT 6 speed.

Here's the deal. I also have a catless H-pipe, axle back and a tune as my only mods. I did do some suspension work too. With just that, my car will run 11.90 at 117. Chances are, his car runs the same. Cat delete and tune are good for 116-117 traps. That means these cars are animals upstairs. He was smart by not racing you from the stop because our cars are dogs from the hole unless you drop the clutch at 4-5k which will only result in tire spin on the street. You raced him on his terms now race him on yours. Demand the red light race only.

Now, with that being said, you have to figure out what is wrong with your car. It should not be trapping at 107 mph with a 12.20 slip. I haven't read the details of your car fully but I would look that over. If your car only makes 107 mph power that you have a killer E.T to go with it. Your 60ft would have to be like high 1.4's or low 1.5's for that to make any sense.

Here's my Coyote.

Dominic Sorresso

13TX,

Part of your frustration is something you can't do anything about. The Coyote is a DOHC motor. Your shifting sooner than he is because the Coyote has a higher rpm power peak than you do. You're slowing down while the Coyote is still pulling.

Here's another example w Corvettes: C4 ZR-1 v C5. Look familiar?

13TX

Wow... Impressive car man. And to be honest, I was just going from memory on the mph. The car is in the transmission shop and the slip is in the console... May have been 108, 109, but definitely was not 110 or higher because I would have remembered that. But anyway, the best ET it has ever run was 12.27 and yes it is a dog on top end. Has 3.73s and a 26" tall tire.Roll racing is not, nor will it ever be, this cars forte. You are absolutely right... I need to get my junk right and run another race on my terms. He knew where his car was strong and refused to run anything but that. Kudos to him for baiting me into a less than optimal race that turned out to be perfect for his car. After I get my car out of the shop, I think I'll beat him from a dig but he will almost definitely be running me down.

Street Lethal

iTrader: (16)

You need to remember how fast you trapped, and where your RPM was, otherwise it is meaningless to say anything in term of thoughts without being able to determine your rate of acceleration. Final gear ratio and RPM gives us your top speed capability, and your running a three speed T-350 with a 26" tire and a 3.73 rear gear ratio, that is all your telling us. Putting aside the fact that your racing a DOHC engine, your heads and cam breath very well to match that, but if your not turning the engine over high, and if your running out of gear, what good is roll racing...

Dominic Sorresso

Doubtful ... especially given that the Coyote is new technology, but I'll reserve judgement until I saw a dyno chart showing power and torque peaks.
Your looking at trap speeds that are 10mph apart. If you were in the 112-113 MPH trap, you might be able to get the advantage at the beginning, but the further past 1/4mile, the further you drop off. I ran a C5Z06 at the track. He was
300lbs lighter. He had me by 2 cars before the 1/8, but finished with me 2 cars ahead. Trap speed diff was 4mph.
Not trying to be a boo-bird. DOHC motors are a different level.

Street Lethal

iTrader: (16)

Why would you say that Dom? OP only got pulled by one car length during the two runs, which is not that bad of a beating. If he had a fourth gear in the tranny, and spun it to 6000-RPM with a 3.42 gear out back, that would be enough to put him ahead right there, especially with that 3500 stall speed converter...

13TX

The brutal truth its that I don't remember specifics about my best quarter mile outside of the ET and I don't have the timeslip in front of me... I apologize. But yes I spun the F out of my junk in the roll race with the coyote.... All the way to 7 grand in every gear. He had a distinct gearing advantage at speed, and it showed. He was able to keep his engine in the range where it made excellent power. That thing just kept pulling. It was infuriating and impressive at the same time.

Dominic Sorresso

Street,

As I said I would reserve judgement looking for dyno chart BUT if you review dyno graphs from a OHV v OHC motors, what you would see is that and OHV motor "noses over" after power peak. OHC not so much. As an example, the LT-5 continues to pull.

I've played w OHV motors for many years w my last being a 84 Xfire that ran low 13's on street tires at 104+ trap speeds. Getting power from a DOHC motor is so much less complicated. Just porting the intake and headers took my car to 400rwhp. And that's from a 5.7L NA motor!
Here's a dyno graph. This one compares several different stages of modification with the last one using larger intake and exhaust cams. Look at how flat the HP curve is at the top. Torque peaks at 5krpm +. So your best bet is a 1/4 mile race where low end torque comes in. After that, it's over.
Amazing motors. You owe yourself a drive.

Street Lethal

iTrader: (16)

Read what you wrote above again and again, this is why it is so imperative to calculate your rate of acceleration. If you datalog you will see that those 3.73's don't allow for proper acceleration after first gear, nor up top, your maxing yourself out once you switch a gear, so while the Coyote is taking advantage, your just making noise. Your 3500 stall speed is perfect for your build, but your gearing is skewed. One car length is nothing to be disappointed about. Lowering your rear gear (numerically) allows for a higher trap speed, but, you need that rate of acceleration to get you there, and this is through proper horsepower, trans gearing, final gear ratio, tire size, etc...

Street Lethal

iTrader: (16)

Well then I will tell you right now, if you really do have a 3500 stall speed converter in that T-350, and if you really did spin it to 7000-RPM in every gear, then forget about LSX swaps, you just need a bigger (lower numerically) rear gear. What good is a 3.73 gear with a 3500 stall speed and 26" tire from a roll? Once that converter flashes those rear gears finish before your RPM band begins. Yes, you will get a great sixty foot with those gears out back, but then what? Put 3.27's out back with that 3500 converter and tire size, and shift at 7000-RPM, and see the difference from a roll, as well as the track, or run a much bigger tire....

skinny z

Just read through this quickly and I haven't seen a real hp to weight comparison. Gearing not withstanding, it may not be a fair fight.
That said, the others that have touched on engine performance (as you have) probably have a point. I would think with a cam that size you be well north of 450 chp, don't you. 450 hp in a 3600 3rd gen should trap 110 easily. 12.20's are expected.
Now something to think about is your exhaust. I have a single Flowmaster in the stock location. I can pick up a couple of mph trap speed just by opening the by-pass I have just in front of the muffler. It changes the air fuel ratio so much at the top end that I can move 4 jet sizes to bring it in-line. The formula that was touched on earlier is 2.2 cfm of muffler/exhaust flow per chp is what's needed before the restriction starts to limit power. Do you think you have over 900 cfm of muffler flow? That's doubtful.
This may not make the difference with you and Coyote but it'll definiely make a difference.
That and put the car on a diet.

Street Lethal

iTrader: (16)

If he is running 12.2, this puts him at approximately 375-RWHP at his weight, so he is on target with the power he should be making at crank, and exhaust work won't make a difference. His trap speed tells the real story, and he stated that they stopped at 120mph, "just under" where he traps, so that would make it an eleven second car, but he is running 12.2 with what I am assuming a good sixty foot, yet his ET is higher than it should be. It is a gearing issue.

Dominic Sorresso

At the end of the day, you are working w a design that doesn't match up. The Coyotes are pretty damn fast especially for a 5L motor. So he's giving you a full half Litre. They respond very well to more breathing. And that's been my experience w the LT-5 as well. The sensation of shifting at 7500rpm, amazing.
Whatever you do to match up at the top, you will lose at the bottom. Tough to get an NA OHV 5.7L motor to put out 550+ chp and still idle at 850rpm w/o VVT.

Street Lethal

iTrader: (16)

Definitely agree with the above, that is why I went turbo.

Dominic Sorresso

He said his trap was about 107.

Street Lethal

iTrader: (16)

His info is everywhere...

120 is a lot more than 107, not slightly above, so the info needed really is all over the place...

skinny z

What is his weight? I didn't see it posted.
Don't you think 12.2x is a damn sight faster than 107 mph or 110 for that matter? My poorly geared (worse than TH350) 3650 pounder traps 108 mph at 12.6 (poor 60'). I run tiny 170cc heads and a 274 degree cam. The OP should crush me. So while it may be gearing holding him back (and I agree), power production certainly is.
Just an observation.

Street Lethal

iTrader: (16)

All I care about is trap speed. That 12.2 is meaningless if 120mph is slightly above his trap speed, and if he is in fact trapping closer to 115mph (which is slightly under 120mph), then 12.2 with a 1.5 - 1.6 sixty foot would mean his gearing is killing him, or, his sixty foot is actually closer to 1.90 since a tenth in the sixty equates to two to three tenths in the 1/4. We need a time slip, because the info he is giving is all over the place. As for weight, an '85 sport coupe with a lighter trans and aluminum heads should be close to 3300 pounds, but again, it is meaningless once we know his true trap speed...

Dominic Sorresso

Trap speed is the truth.

skinny z

Agreed. This is why I'm saying that with the info we have ( less than 110 mph but with a 12.2 ET) the power production isn't what it should be.
The heads notwithstanding, and I haven't investigated what the peak cfm is on them, that engine should make 450 chp. And it isn't.
Better gearing, with traction may drop him into the 11's especially if he's less than 3400 lbs. Trap speed should be 110 or better easily.
To further support your gearing angle (and as I said, I agree) our analysis of our own drag strip results shows a 2 -3/10ths better ET if we go from the current 700R4 we're running to a close ratio 4 speed trans.

Dominic Sorresso

Here's a very interesting vid of a dyno test w a motor that's at least analogous to the one we're discussing. Looks like a switch in intake may be in order altho no real difference in where the power peak is. More power under the curve tho.

skinny z

Nice video. I"ve always thought that this was the way to go with a "street " engine, even one with a 294 solid roller cam. Could be the OP would benefit from change like that like you said.
Something worth noting, is that the OP said he is shifting at 7000. Thats probably 700 rpm beyond peak horsepower so with just that, he is wasting ET. Shift a little sooner perhaps...
That said, as we all know, the dyno tests are a little skewed. Those wonderful headers and short exhaust combine to give the best breathing and help the bottom line horsepower production.

Dominic Sorresso

Absent any other real numbers from the OP, thought this was a good indicator of which way to go. As you point out, this is a pretty naked motor so not sure the results will be of this magnitude, but directionally it is worth seeing. The Coyote will still have a higher power peak w a flatter downturn. If the OP is shifting at 7K, way too high IMO, if he shifts at lower rpm it may keep him in power band but Coyote will continue to extend. As an example, w a 3.73 gear and 19" wheels, I'm going thru the traps in 3rd @ ~ 118mph+ and right at power peak of 6800-7100rpm. My shift light is set for 7200 figuring the shift takes place at 7400 w reaction time. It's the big end where the DOHC really comes into its own.
With a peak of 6k, you shifted again if you have a gear left.

13TX

I said 120 was slightly above where I trapped, just to clarify. But screw it I'm going to the Trans shop and digging the timeslip out

13TX

Called my buddy that runs the trans shop, had him dig it out. You guys were right... It was 117, not 107. I'm really sorry for putting out incorrect information- I would have sworn it was lower than that. Either way, this car still under performs in my book and its going to have to undergo a few changes.

skinny z

Now 117 IS impressive and more along the lines of what a engine with that cam and any decent heads should be able to do.
Still, 7 grand is a little above your peak power (from other similar builds). There may be a benefit to shifting a little earlier but as been pointed when comparing it to the Coyote, a close ratio trans (and more gears) is the way to go if you want to keep your engine in the "powerband". (That is between peak torque and horsepower).
Optimizing your gearing for the drag strip is another thing altogether.

13TX

Yeah. You guys have helped me figure out alot in this thread. It was a square peg- round hole type situation. I thought my car had enough juice to beat him at a race I knew was not optimal going in. Clearly that was not correct. I have a few tweaks to make before we run it back under my terms (he will have DRs this time tho), but the bottom line is that my car is done being ran from a roll. Any roll. Never again. That's just not what it is.

13TX

You guys are right. I let it hang too much and ran it too high in each gear before shifting. Idk why... Just adrenaline and trying to do something different to possibly affect the outcome. But yes I figure this cam makes peak power around 6200 or so. I'll keep the shift light set at 63 til the cam swap.