Shocking results revealed: Boss IM vs Ported Stocker

[4VFTW]

hit the track last night to see how the car ran with my ported stock manifold vs the Boss in as close to an apples to apples test as I could create. here are the results....

Boss IM , 1700' d/a ,10mph headwind, 19" saleens all around.

Ported Stocker, 1250' d/a , SVE drag wheel setup(50lbs lighter).

the Boss '60'd, 1/8 e.t and mph'd better and 1/4 e.t'd better at a weight and d/a disadvantage
the Stocker managed best 1/4 mph ever.

I do think some of the shift points were too high on the stocker tune...I know 3-4 was at 7400 and I believe the 2-3 was 7200 maybe a tick higher.
looks like I will have to port the Boss and go back either this friday or next week and dig a little deeper into this mystery.

 

[blackcoyote13]

The last ported stock manifold review I saw showed losses throughout the powerband.

 

[SCalla1384]

Boss intake FTW!!

run the boss intake again with those wheels, and closer to 1250' DA.

And then port it. That would be an ideal comparison.

 

[4VFTW]

The last ported stock manifold review I saw showed losses throughout the powerband.

without knowing any details , I dont put much stock in dyno #s. I have never dyno'd a car to see what it put down, I test at the track. has anyone done a before/after track test of a ported stocker? best I can offer is a before/after of a ported Boss and that will be coming soon.

 

[11_Ingot5.0]

Having a ported boss intake will it gain few more hp?

 

[dirtyd88]

Having a ported boss intake will it gain few more hp?

Local shop did a port job on the Boss IM, and it improved the TQ curve a little to smooth it out, and also brought up the peak HP a few ponies.

 

[Blazer707@TBR]

Good comparison marc, what shift points was the car shifting at on the boss?

 

[04compgt]

Marc, if you really want to see a difference in MPH with the boss I would recommend at least 7500 rpm shifts. In my case I shift mine at 7700 and trap 123mph in the 1/4 N/A. I saw a 2 mph gain from 7100-7200 shifts to 7700 shifts. It seems the more you rev the boss the happier it is. On to the stock manifold, I tuned a local friend's car (Fabbed5.0) with the stock manifold, we tried shifting it at 7200-7300 with mph loss so I told him to short shift at 6900-7000 and he was able to trap 120 mph in the 1/4 from 118. Good luck in your upcoming testing.

 

[IDWALKU]

6900 is where i shift my car and im stock manifold and i trap 121 with big and littles cai tune hpipe mufflers . 7200-7400 will drop me in the 117-118 range real quick

 

[dirtyd88]

Cars with stock IMs make peak power in the 6600 RPM range, so 6900-7000 makes the most sense being that's where you will probably start to decrease the most in power if you go any higher.

I have my rev limiter set at 7200 in my tune for this reason. Anything above that is pointless.

 

[4VFTW]

Good comparison marc, what shift points was the car shifting at on the boss?

1-2 7200, 2-3 and 3-4 7500.

Marc, if you really want to see a difference in MPH with the boss I would recommend at least 7500 rpm shifts. In my case I shift mine at 7700 and trap 123mph in the 1/4 N/A. I saw a 2 mph gain from 7100-7200 shifts to 7700 shifts. It seems the more you rev the boss the happier it is. On to the stock manifold, I tuned a local friend's car (Fabbed5.0) with the stock manifold, we tried shifting it at 7200-7300 with mph loss so I told him to short shift at 6900-7000 and he was able to trap 120 mph in the 1/4 from 118. Good luck in your upcoming testing.

6900 is where i shift my car and im stock manifold and i trap 121 with big and littles cai tune hpipe mufflers . 7200-7400 will drop me in the 117-118 range real quick

Cars with stock IMs make peak power in the 6600 RPM range, so 6900-7000 makes the most sense being that's where you will probably start to decrease the most in power if you go any higher.

I have my rev limiter set at 7200 in my tune for this reason. Anything above that is pointless.

I agree with you guys that the shift points were too high, watching that tach I was puzzled why it was shifting that high. silly me I didnt test the tune on the street prior to hitting the track or I would have asked for revision to lower them. the last pass I made was just to get a datalog of the shifts but they redlighted the lanes twice in line to stage and my glitchy $50 laptop powered down during the log and wouldnt restart:nonono:

high shifts or not I just dont see the car picking up 3mph on the backhalf...my cars mph never fluctuates more than .5mph even when the Boss tune was shortshifting the mph was consistent.

the '60 and '330 times tell me the Boss has the edge...hard to overcome that deficit on the back half

I will give the Boss another shot on equal footing and see what it has to say.

 

[dirtyd88]

Only thing I guess I'm puzzled on is that fact the Boss IM 60s and 330s better with the loss of the low/mid TQ...

 

[11_Ingot5.0]

Is there a how to to port a boss intake? I want to do it right n not sand away too much

 

[BMR Tech]

You always want to keep an auto car, especially with a Boss Intake....in 1st gear as long as possible. It is geared aggressively, and will be the fastest the car accelerates (rate) through the entire run - so keep it there as long as possible.

It is also, typically, better to shift at a higher RPM, in the lower gears - compared to lower shifts in the lower gears.

I'd be willing to bet, you are giving up a few mph alone by the method at which the car is shifting. For the stocker, I would do 7200/7300 1-2.....7000 2-3 and 6700/6800 3-4.

With the Boss, I would try 7700 1-2......7500 2-3.....and 7300 3-4.

 

[IDWALKU]

idk my car back halfs amazing . my buddy has long tubes and a drive shaft over me . he traps 97 in the 1/8 122.11 in the 1/4

(same night same track) im 94mph in the 1/8 and 121.97 in the 1/4 so id say 6900 rpm shifts back half a car pretty well

 

[BMR Tech]

Yes, 3-4 shifts in the <7000 range will typically result in very good traps.

 

[4VFTW]

Only thing I guess I'm puzzled on is that fact the Boss IM 60s and 330s better with the loss of the low/mid TQ...

the 3700 stall and steep gear overcome any loss of torque.

the experiment continues...I am porting the Boss now and will see how the car runs , if there is no real gain I may retry the Stocker with a revised tune.

 

[FleeMan]

So this should confirm that the Boss is a great bolt on to any GT. And IMO, dyno numbers mean absolutely nothing.

 

[blackbeast12]

Ported cobra jet manifold is the way to go ...n/a

 

[dirtyd88]

the 3700 stall and steep gear overcome any loss of torque.

the experiment continues...I am porting the Boss now and will see how the car runs , if there is no real gain I may retry the Stocker with a revised tune.

Ahhh...

But even then, would that not keep the same scenario true with the stock IM?