93 gt long tubes vs shorties??

[Ramsey 93]

My current setup is stock 93, with track heat intake u/l, stock cam, stock heads,bbk fendor mount, pullies, shorties, catless h, flowmasters, t5.
I am about 90% installed on my nitrous setup (100wet hit), going to wait for my tune to spray.

Should i keep the shorties or trade for long tubes?

 

[NIKwoaC]

Long tubes just mean more power. They are more difficult to install and could cause ground clearance issues. Also, they could interfere with other components in the engine bay (steering shaft, for starters). Its up to you beyond that.

 

[Ramsey 93]

Long tubes just mean more power. They are more difficult to install and could cause ground clearance issues. Also, they could interfere with other components in the engine bay (steering shaft, for starters). Its up to you beyond that.

They are currently installed on a buddies car, and he wants to swap; so i am not worried about fitment or clearance..i am more worried if i am going to lose low end torque?

 

[Grn92LX]

You will gain low end torque and across the board. Straight up swap? Go for it then

 

[Ramsey 93]

You will gain low end torque and across the board. Straight up swap? Go for it then

straight up swap.. i will making the swap this weekend.

 

[04gtboy]

I put BBK longtubes this winter and had no problems with then . You have to take the nut off the motor mounts and jack up the motor to get them in .

 

[5spd GT]

For comparisons sake, I will put this out there.

Okay, I had a 162k bottomend (1993). This was topped off with AFR 165, OTB Performer Intake, and a custom camshaft, rusted out Mac 1.625" headers (pinched).

I decided to make a few changes, after a couple circumstances. The local track (that I frequent most) is a 1000 ft. track. Best run, off the street was a 10.65 @ 97.98 MPH with the combination above.

Okay, the changes I made were, rebuilding the bottomend (306). I used Probe's 030-10682 pistons (9.6:1 now), with more swept volume that will increase compression. KC did the bottomend.

I also replaced the old rusted short headers, with new BBK Longtubes and a new Offroad H (no dents like my last pipe). I then had Tom Moss port the lower to match the AFR 165cc heads, and he matched them great. Looking down the port, it matched the flange nicely. I even trimmed the gaskets (not done before), cleaned everything as clean as possible as well.

So these three changes were made:

- 306 (slightly more compression)
- Longtubes with H-pipe
- Ported lower to match AFR 165

After several runs throughout the next year, the best run I could get was 10.56 @ 99.31 MPH.

I kept the same exact timing, fuel pressure, driver weight, tire pressure, etc. I noticed a little more pull about 5300+ RPM, which I attribute to the lower porting by Tom.

A total gain of 1.33 MPH and .09 seconds. So roughly 13.30 HP...

Up top the HP/TQ power curve is identical, but the lower/mid range will improve a bit. That is why many do not see huge gains at the track, because you race 3,500 + RPM, not idle to 3,500 RPM.

 

[joel5.0]

Up top the HP/TQ power curve is identical, but the lower/mid range will improve a bit. That is why many do not see huge gains at the track, because you race 3,500 + RPM, not idle to 3,500 RPM.

View attachment 306949 ... If "Up top the HP/TQ power curve is identical"....I wonder why Pro Stock and NASCAR don't use shorties......and they race "3,500 + RPM" 100% of the time.

Pro Stock

NASCAR
View attachment 306951

 

[5spd GT]

View attachment 306924 ... If "Up top the HP/TQ power curve is identical"....I wonder why Pro Stock and NASCAR don't use shorties......and they race "3,500 + RPM" 100% of the time.

Easy, because every little bit helps.

If you can have identical up top, but get more at low to low-mid, why not?

However, their budget seems to be a bit higher than ours, right? Correct me if I am wrong.

They also do not race "3,500 RPM" and up, all of the time.

Two words: ___ ____

If you want to debate with Larry Meaux, Darin Morgan, etc. on the "identical" part, then have at it.

The collector is where a lot of power comes from, and a longtube provides that. Many of our collectors are at 7"-10", when they should be 15"-18". I am not aware of any collector length restrictions on a NASCAR or PRO STOCK engine.

I also can only post my own personal experience with the car I drove for 3.5 years.

I can also provide the "longtube" experience from my friend's '02 GT if you would like as well.

I can also...well N/M.

 

[Boostedpimp]

I'd say since it's an even swap go for it.. as long as you don't mind ground clearance problems or making plug changes even harder.

but if I were to choose when buying new and the car was mostly stock or stockish i'd go with just shorties for ease of install and plug changes.. long tubes don't give you much more for how much more they are to purchase and the more time to install and deal with in my opinion

 

[wildstang90]

I just put the BBK LT headers in my 90 about 3 months ago. I have no ground or steering problems. They were alittle harded to put in but still not a big deal. If I had a set of shorties in that were in good shape I would not bother replacing them with LT.

 

[25thmustang]

My car might not be fast without my long tubes. One of the largest gains I ever saw was shorties and a catted H to long tubes and a Prochamber, waaaay back in the day!

 

[joel5.0]

Easy, because every little bit helps.

If you can have identical up top, but get more at low to low-mid, why not?

However, their budget seems to be a bit higher than ours, right? Correct me if I am wrong.

They also do not race "3,500 RPM" and up, all of the time.

Two words: ___ ____

If you want to debate with Larry Meaux, Darin Morgan, etc. on the "identical" part, then have at it.

The collector is where a lot of power comes from, and a longtube provides that. Many of our collectors are at 7"-10", when they should be 15"-18". I am not aware of any collector length restrictions on a NASCAR or PRO STOCK engine.

I also can only post my own personal experience with the car I drove for 3.5 years.

I can also provide the "longtube" experience from my friend's '02 GT if you would like as well.

I can also...well N/M.

I don't see Larry Meaux, Darin Morgan, etc. posting around here........ and yes, leaving everything else "identical" is an evaluation procedure that is as valid as a 3 dollar bill with the picture of Mickey Mouse on it.

So Pro Stock and NASCAR "do not race "3,500 RPM" and up, all of the time."?

Now, regarding your conclusion regarding ST's vs. LT's based on your experience(s).....

Up top the HP/TQ power curve is identical, but the lower/mid range will improve a bit. That is why many do not see huge gains at the track, because you race 3,500 + RPM, not idle to 3,500 RPM.

Translation = LT's do not have anything to offer "up top" when compared to ST's. LT's gains are limited to nominal gains in the lower/mid range window only.

Let me see..... View attachment 306900 .... you take a setup and leave it as close to the original ST's "baseline" to draw conclusions regarding LT's performance gains. IOW, you change exhaust characteristics only, and conclude the obvious..... questions:

1. How would those results be affected by increasing A/F in the upper rpm range?
2. How would those results be affected with a different fuel map across the whole rpms range?
3. How would those results be affected by modifying the spark advance curve?

If none of the parameters affecting performance are modified around that "variable" to try to optimize it....... any derived performance conclusion regarding the variable under "evaluation" is questionable and not valid.

 

[5spd GT]

I don't see Larry Meaux, Darin Morgan, etc. posting around here........ and yes, leaving everything else "identical" is an evaluation procedure that is as valid as a 3 dollar bill with the picture of Mickey Mouse on it.

Why would they? They would have to deal with post like yours.

Your view of valid is different than my view of valid. Your view of identical is different than my view (Webster's) of identical - "having such close resemblance as to be essentially the same."

So Pro Stock and NASCAR "do not race "3,500 RPM" and up, all of the time."?

Pit Stop

Now, regarding your conclusion regarding ST's vs. LT's based on your experience(s).....

Translation = LT's do not have anything to offer "up top" when compared to ST's. LT's gains are limited to nominal gains in the lower/mid range window only.

Let me see.....you take a setup and leave it as close to the original ST's "baseline" to draw conclusions regarding LT's performance gains. IOW, you change exhaust characteristics only, and conclude the obvious..... questions:

1. How would those results be affected by increasing A/F in the upper rpm range?
2. How would those results be affected with a different fuel map across the whole rpms range?
3. How would those results be affected by modifying the spark advance curve?

If none of the parameters affecting performance are modified around that "variable" to try to optimize it....... any derived performance conclusion regarding the variable under "evaluation" is questionable and not valid.

My buddy's '02 GT was tuned by a well known shop in Memphis, after the swap.

So what if the short tube headers were not "optimized"? Now we have to optimize the long tube headers? Sounds like a double standard.

The typical 4:1 short/long tube header gets more gains from the collector, not the length.

A longtube (due to length) tunes in at a lower rpm, but a short tube header tunes in at a higher rpm. The short tube has a quicker return time with the pressure wave, for those upper RPM's. Again that is why, the difference is very small between the two.

Technically, as RPM increases, the header primary length should decrease based on the target RPM.

IF I was starting from scratch, and I had a $200-$300 more, I would go longtubes.

 

[Ramsey 93]

Last week i ran 14.7 at 95.7 with street tires and a ****ty second gear.. Friday i should have the same conditions and i will see what i run.. I will post results. Nothing will change but the exhaust. climate should be close to the same.

 

[5spd GT]

Last week i ran 14.7 at 95.7 with street tires and a ****ty second gear.. Friday i should have the same conditions and i will see what i run.. I will post results. Nothing will change but the exhaust. climate should be close to the same.

I prefer to see dyno results, with less variables.

I gained 3 MPH after I changed my alternator to a 3G.

Slight changes in the atmosphere can show up at the track.

My next exhaust will be longtubes on my coupe; they also sound better.

Let us know how it goes, as it should be positive.

 

[Ramsey 93]

I prefer to see dyno results, with less variables.

I gained 3 MPH after I changed my alternator to a 3G.

Slight changes in the atmosphere can show up at the track.

My next exhaust will be longtubes on my coupe; they also sound better.

Let us know how it goes, as it should be positive.

Yeah, im not looking for a crazy performance gains.. but i do want the sound and i assume they could only help.... i just wanted to make i wasnt gonna have a bunch of low end torque loss.. i will have a write up when the swap is finished. thanks for all your guys help.

 

[5spd GT]

Yeah, im not looking for a crazy performance gains.. but i do want the sound and i assume they could only help.... i just wanted to make i wasnt gonna have a bunch of low end torque loss.. i will have a write up when the swap is finished. thanks for all your guys help.

Oh no, you will gain TQ. They will help out the sound and will not hurt you at all.

 

[85_SS_302_Coupe]

My car might not be fast without my long tubes. One of the largest gains I ever saw was shorties and a catted H to long tubes and a Prochamber, waaaay back in the day!

Same here... i went from shorties and an offroad H to Mac full lengths and a Pro Chamber and it just felt like the engine revved so much cleaner and freer and the mid to top end was much stronger.

Another thing i really like about full lengths is how easy it is to swap out the mid pipe and make exhaust adjustments in general...since the flanges are all right under the car. It does suck installing the headers the first time around, but how often do you really need to get them back out?

Lastly, i'd recommend definitely going with a full flange header, because pretty much all the separate flange styles are going to warp and make it a PITA to bolt back on after being unbolted (i've had this issue with shorties too however).

 

[5spd GT]

Another thing i really like about full lengths is how easy it is to swap out the mid pipe and make exhaust adjustments in general...since the flanges are all right under the car. It does suck installing the headers the first time around, but how often do you really need to get them back out?

Lastly, i'd recommend definitely going with a full flange header, because pretty much all the separate flange styles are going to warp and make it a PITA to bolt back on after being unbolted (i've had this issue with shorties too however).