Mustang SN 95/99 Owners Unite

[Smike]

SN95 and SN99 racers,

 

We all want close and competitive racing here. Race to race and region to region. I'd rather not dwell on how the rules have changed or how the class has evolved. My focus is forward. We should share what we know that makes us fast and how we can collectively tackle the F-body cars.

 

Let's use this area to share setups, feedback, and updates.

 

April 2013 Mid Ohio Great Lakes

MW #302 and I had two very closely matched SN95s. 0.3s off each other in qualifying. Down 2.5-3s off the F-body cars. Video to follow of how close the cars are.

 

Achilles Heal #1 - 4.6l power. I am down 20hp/30tq off the 260/310 max. Power curve is less than optimal. Weight is ~3225 full tank. The power I have is the power this motor will make. Every class rule consideration has been used. Nothing to hide here, happy to produce the dyno chart. I do not believe just adding power will make 3s difference.

 

Achilles Heal #2 - T-45 and 0.67 5th gear. #302 was able to pull me slightly 4th gear v. 4th gear (power shortage on my part). At 5th gear he pulled a car length before the braking zone. He has the RR 5th gear. Currently, car has a 3.73 rear gear. 4th gear terminal speed at 6000 RPM is 120 mph.

 

Group Thought 1: lower rear get to effectively create a 4sp trans. I am leaning towards a 3.31 rear gear. New 4th gear terminal speed would be 135 (139 at limiter). Only the longest of tracks would the speeds reach north of 135 (Road America, etc). 3-4 shift would put the car back at 4600-4700 well within the meat of powerband.

 

Forward actions:

Log lateral g-forces for in corner information. Track width is not fully maximized to the rules.

 

Others thoughts and findings?

 

MG #108 GL

[ShadowBolt]

I bought Tony G's 2002 SN95 with 4.6. It had a stock engine with underdrives (never run the lower pulley on the cheap sets) and long tubes. made 252/292. I built an aluminum block high compression engine to replace the stocker when the chain tentioner broke and bent the valves. Spent a fortune and dynoed 252/293. The underdrive set-up and a missed gear caused the oil pump to fail halfway through the first season. Bought a Craigslist complete engine and it had a spun rod bearing so I pulled the heads and dug out the old orignal block that came in the car and put them together with new gaskets and this year with smoke on startup and an engine so loose it will not hold the car on the trailer in first gear, I pulled 264/299 this year. Go figure.

 

I can tell you I still believe the Mustangs are giving up something to the Fourth Gens but I don't think it's much. I believe a SN95 driver would turn faster laps in a Fourth Gen after he got used to it and Vice Versa.

 

I can tell you that you can win in a SN95. We have a new guy (Aaron... Suck Fumes) that is racing in Texas doing everything we are told you can't do and he is still winning. 3:27 rear end, no PM3L or Panhard Bar. The car is not low and does not have stiff springs but he is as fast as the guys will all that stuff and the Fourth Gens!

 

I still think the Fourth Gen is a better race car because of all the things we have been told over the years that you need to go fast (like coil-overs and a torque arm, aero) but I know for sure you don't have to have that stuff to win.

 

JJ

[suck fumes1548534743]

All the wives tales you read about how a 4 link mustang setup sucks etc. it's just that...wives tales! Haha. It depends largely on driving style and being smooth, emphasis on smmoootthhh. Pre 2005 stangs can be twitchy and tail happy if not driven correctly. Smooth steering inputs play a huge role on how your car behaves. Sure I get pulled on at the starts due to lack of torque against the 4th gens but from what I've seen so far the 4th gens don't handle any better than a well setup mustang. On top of all that my rear diff was allowing the inside wheel to spin so I couldn't even launch out of the corner like I wanted too. I just ordered a better diff so that will change hehe.

[Smike]

Video from Saturday and a few laps of Sunday:

 

Have sources a 3.31 rear end. At Mid Ohio, it would save a 3-4-3 shift in Thunder Valley and 4-5-4(3) shift at China Beach. If you watch the video, you'll see how drastic the 5th gear is for the car.

 

Agree on the live rear end. I don't have any pan-hard or PM3L either.

 

All the wives tales you read about how a 4 link mustang setup sucks etc. it's just that...wives tales! Haha. It depends largely on driving style and being smooth, emphasis on smmoootthhh. Pre 2005 stangs can be twitchy and tail happy if not driven correctly. Smooth steering inputs play a huge role on how your car behaves. Sure I get pulled on at the starts due to lack of torque against the 4th gens but from what I've seen so far the 4th gens don't handle any better than a well setup mustang. On top of all that my rear diff was allowing the inside wheel to spin so I couldn't even launch out of the corner like I wanted too. I just ordered a better diff so that will change hehe.

[suck fumes1548534743]

Yah your gearing is killing you huge. That's why I never understood why everyone thinks using them is so grand. Getting off the line at the start is a very small part of the race. The rest of the time at most tracks you're never in 2nd gear so having steep gears hurts you more than helps cause that extra torque curve starts to drop off and even out with the rest in 3rd.

[ShadowBolt]

One other thing to consider.....

If you have long tubes you will not be changing the clutch at the track. You can't remove the trans with the long tubes in place. You either have to remove them or pull the engine (that's what I used to do). To get around this and the fifth gear issue (there is a RR fifth available now for the 3650 that was not around when I changed over) I purchased an Astro Performance A5. This gave me a .89 fifth and the chance to change a clutch at the track if I want to. The A5 (just a beefed up T5) can be pulled with the long tubes in place.

 

JJ

[suck fumes1548534743]

How is the A5 diff than a 3650 in terms of being able to pull it out?

[ShadowBolt]

How is the A5 diff than a 3650 in terms of being able to pull it out?

 

The bellhousing on the 3650 (and T45) is wider and will not clear the tubes. When you go to an A5 (or T5) you have to use a Quicktime scattershield to mate it with a 4.6. This requires you to run a different clutch also. The A5 has a larger input shaft. I carry a spare clutch with me. I would hate to have to change it at the track but if you drive all the way to Hallett and lose it the first day.......

There may be a brand of headers that will allow the trans to be pulled with the headers in place but not on mine (BBK) or Jeremy's.

 

One thing I don't understand. There is another Mustang in our region that runs a 4.6 with shorties and he makes as much power as I do with the long tubes. I was told he installed a newer designed (stock) set of heads that make more power. I have not looked into this to know for sure. I can tell you I hate the long tubes. Everything is a bitch! Even changing the starter. If I have to pull a head the whole engine is pulled. It's way easier than trying to remove even just one header.

 

JJ

[suck fumes1548534743]

I was talking to him too and that made no sense. I bought BRAND NEW oem PI heads for my car 3months ago and his numbers were about the same as mine and I have longtubes. Something smells fishy to me! If there was some special new design I would have heard about it and used them! I have a few vendors that have the inside scoop on ford stuff and no one ever told me anything about em.

[Smike]

Do have long tubes. If I have clutch issues, I wont be changing it at the track anyway. That's when I park the car for the weekend.

 

Next event is Putnam, 3.73 is not an issue with its shorter straight. I typically top out 4th before the braking zone. And 3rd, 2x in 2 sectors.

 

Will swap it out if I have time. Otherwise, after that event.

[ShadowBolt]

I was talking to him too and that made no sense. I bought BRAND NEW oem PI heads for my car 3months ago and his numbers were about the same as mine and I have longtubes. Something smells fishy to me! If there was some special new design I would have heard about it and used them! I have a few vendors that have the inside scoop on ford stuff and no one ever told me anything about em.

 

Maybe it's not the heads? I never checked it out I was just told about them. If there is zero difference in the long tubes and the shorties I will change mine out at the end of the season. It would be great to be able to pull one or both heads and not have to pull the engine!

 

JJ

[blk96gt]

 

One thing I don't understand. There is another Mustang in our region that runs a 4.6 with shorties and he makes as much power as I do with the long tubes. I was told he installed a newer designed (stock) set of heads that make more power. I have not looked into this to know for sure. I can tell you I hate the long tubes. Everything is a bitch! Even changing the starter. If I have to pull a head the whole engine is pulled. It's way easier than trying to remove even just one header.

 

JJ

 

That would be me. I don't know why my car makes what it does. The main differences in our engines would be:

- 96 engine with new casting PI heads and intake

- 11 cc dish pistons (96-98 had 11cc, 99-00 had 18 cc, and 01-04 had 16 cc)

- Return style fuel system (96-98[?]) vs. returnless (99+)

- Bored .020 over after pistons cracked the first time.

- I went with 11cc dish pistons for the rebuild (and even used stock style hypereutectic piston

I haven't had an "official" dyno yet, but it looks like I'll be around 262-263 RWHP.

 

You're more than welcome to make any claims you want. I have gone through 2 engine rebuilds in two weekends because I couldn't get it rich enough (turned out the thing had a chip in it, which was installed in 1998...) First rebuild required boring the cylinders, second only the pistons were replaced. Both times were the result of detonation.

 

I ended up using the BBK timing adjuster and pulling 3 degrees of timing, going to 24lb injectors, and increasing the fuel pressure to 46 psi at idle to get this thing to a decent AFR.

[ShadowBolt]

 

One thing I don't understand. There is another Mustang in our region that runs a 4.6 with shorties and he makes as much power as I do with the long tubes. I was told he installed a newer designed (stock) set of heads that make more power. I have not looked into this to know for sure. I can tell you I hate the long tubes. Everything is a bitch! Even changing the starter. If I have to pull a head the whole engine is pulled. It's way easier than trying to remove even just one header.

 

JJ

 

That would be me. I don't know why my car makes what it does. The main differences in our engines would be:

- 96 engine with new casting PI heads and intake

- 11 cc dish pistons (96-98 had 11cc, 99-00 had 18 cc, and 01-04 had 16 cc)

- Return style fuel system (96-98[?]) vs. returnless (99+)

- Bored .020 over after pistons cracked the first time.

- I went with 11cc dish pistons for the rebuild (and even used stock style hypereutectic piston

I haven't had an "official" dyno yet, but it looks like I'll be around 262-263 RWHP.

 

You're more than welcome to make any claims you want. I have gone through 2 engine rebuilds in two weekends because I couldn't get it rich enough (turned out the thing had a chip in it, which was installed in 1998...) First rebuild required boring the cylinders, second only the pistons were replaced. Both times were the result of detonation.

 

I ended up using the BBK timing adjuster and pulling 3 degrees of timing, going to 24lb injectors, and increasing the fuel pressure to 46 psi at idle to get this thing to a decent AFR.

 

I'm not saying you are doing anything wrong at all. Jeremy had told me you had some new casting heads that made more power. I never looking into it.

 

 

JJ

[suck fumes1548534743]

Yah I'm not trying to claim or blame anything just think its weird how one year model will make higher numbers without longtubes. Just out of curiosity what is your AFR now? And when it was detonating?

[blk96gt]

That wasn't aimed at you Jerry. That was in reference to Aaron claiming something smelled fishy.

 

Any of you are welcome to look over the car any time you want. I bought the car second hand. I've gone through it as best I can. If you guys can find something wrong with it I will be more than happy to fix it. My goal is to have a car that doesn't blow up every time I go to the track and have fun.

[blk96gt]

Yah I'm not trying to claim or blame anything just think its weird how one year model will make higher numbers without longtubes. Just out of curiosity what is your AFR now? And when it was detonating?

 

AFR is 12.5 now. Before it was around 13.2. I don't know when it was detonating. Wasn't doing it on the dyno. Both tImes the engine blew all the pistons showed signs of detonation. The first time it blew I had 3 pistons with cracked ring lands. Second time I had 2 pistons with cracked ring lands. With a helmet on and having poor hearing I was never able to hear any detonation.

 

My theory on the power difference is the piston dish. I don't know as much about engines as you guys so I could be wrong.

[ShadowBolt]

Yah I'm not trying to claim or blame anything just think its weird how one year model will make higher numbers without longtubes. Just out of curiosity what is your AFR now? And when it was detonating?

 

AFR is 12.5 now. Before it was around 13.2. I don't know when it was detonating. Wasn't doing it on the dyno. Both tImes the engine blew all the pistons showed signs of detonation. The first time it blew I had 3 pistons with cracked ring lands. Second time I had 2 pistons with cracked ring lands. With a helmet on and having poor hearing I was never able to hear any detonation.

 

My theory on the power difference is the piston dish. I don't know as much about engines as you guys so I could be wrong.

 

I don't think the pistons are making that much difference. The Teksid block I built had pistons that DSS Racing said were as high compression as I could get and still run pump gas. If I remember it is a 3CC dish piston that came in the NON PI headed engines. Don't quote me on that but as I said before the high compression engine I built made just a little more power than the stock compression engine did. We (Aaron and I) just want to learn how to make power without the long tubes. Since you are doing it we hope to learn from you.

 

JJ

[blk96gt]

I wish I could give you guys more insight! From what I've figured out so far by searching the web, the 96-98 PI swap cars will typically have around 10-15 HP more than a 99+ with the same mods. Whether this is from the pistons, fuel system (return style on 96-98), or the difference in stock tunes between the 96 and 99 I don't know.

 

With a good tune and bolt ons (exhaust, throttle body, UD pullies), a lot of 96-98's I saw were making 270+ horsepower.

 

I plan on putting together another engine soon (I don't think this one is going to last), so I will be interested to see what kind of power it makes. I'm still trying to decide if I want to do an aluminum block or stick with iron. My water temps seem to stay around 205-215*, and I'm worried that might be too warm for the aluminum block.

[suck fumes1548534743]

Aluminum block is a waste of money. Mine usually runs 195-200 all race and seems to be happy.

[blk96gt]

The main reason I would like to go to the aluminum block is to save some weight. The car was 3306 with me and 1/2 a tank of fuel. I've got 150 lbs I've got to get rid of. Removing the passenger seat may get me 25-30 lbs or so. Short of losing weight myself (not going to happen), my only options would be aluminum block (min. weigth would be 3250 with that), or start cutting out wiring (not too thrilled about this). Maybe there's some weight savings I'm missing somewhere else as well.

 

Also, do you still have the stock cooling setup? Boxed in radiator? I've got a Mishimoto and its boxed in. Still trying to figure out what I can do to get it to run a bit cooler.

 

How many bottles of water wetter do you guys run in your cooling system, if any?

[suck fumes1548534743]

You won't save overall weight cause they make u run 50 pds of ballast extra. So you're only moving the weight which isn't a bad thing I guess.

[suck fumes1548534743]

I have a mishimoto but we drilled two big holes in my bumper so it can breathe better. Don't use water wetter that stuff doesn't do anything.

[ShadowBolt]

I run the stock two row rad. and it never gets past 200. I changed it out prior to Hallett last year just because the fins were all bent over. It was still cooling very well. If you don't have the radiator wind deflector it WILL run hot. At least mine did.

 

I agree the alum block was not worth having to run the extra lbs. Turn in was a little better but.....

 

 

JJ

[Smike]

I am running a 98 4.6l iron block, 2000 PI heads and PI intake. Unknown if they put in the PI cam to this motor when they built it. Not likely based on what I have found. 3in AL rad with 2 fans on a switch. Runs cool.

 

I had an issue with the gas tank. The first owner added a 190lph pump and with the 98 system, modified the gas bucket to fit it. In doing that, hard corners would cause the fuel to move away from the pump and starve the motor. If completely full (to the top of the filler neck), I could last a 45 min race. Downside is that I cannot get to my min weight that way. New pump assembly en route and tank is out right now to fix that. If I can finish at 1/4 tank - I will be 3175.

 

I will measure my track width next time I work on the car.

[suck fumes1548534743]

I always weigh around 3280-3300 after the race. Using 1 3/4" roll bar tubing made it heavy but even if it were thinner it would still be 70-80 pds overweight. Not sure what else I could pull out that would make it any lighter.