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Boss intake vs gt intake revisited

pufferfish

Supporting Vendor
1,094
66
Maryland
well folks, i humbly tuck my tail. i was wrong. the gt intake may be the best on paper, but the boss intake pulled it off this weekend.

to recap, i blew my gt motor and replaced it with a boss motor. i had dyno tuning done with the gt and boss intakes. the gt made 429rwhp/413rwtq. the boss made 441rwhp/387rwtq. on paper, the gt intake gives up only 12hp to gain 26tq. actually, the torque gains were as high as +33 along the curve, but none of that matters any more...i have seen the light!

so, 2 days before SVTSuperfest, my 5th gear synchro died. I decided to go anyhow and just work on my line and play miata for a weekend (corner carver with no straight line speed). on friday, i ran my gt intake, as i normally would on any given day. i was stuck in the 2:18/lap range with top speed of around 120. i tried to get the engine to rpm as much as possible in 4th, but couldn't get more than [email protected] (and it was a struggle to get it there) and then dumping to 6th only allowed 5 more mph. saturday, i waffled back and forth, whether to try out the boss intake or leave well enough alone. my friend sean said to just go for it, so i did. WOW, what a difference!

the power curve of the boss intake is almost flat as a board from 6.5k to 8k. with 430rwhp at 6.5k, peaking at 441 at 7.4k and holding that peak to 7.7k, then falling back to 430 at 8k. thats just a lot of high rpm range to work with and it showed. i was able to easily reach [email protected] in 4th gear and then dump to 6th to bog its way to 140mph climbing the back straight. with this and a bit more familiarity with the track, i clicked off consistant 2:11's with a best of 2:10.29.

so, while the gt intake torque curve is very desireable over the boss' for wheel to wheel racing, where you find yourself out of the optimum rpm range quite often, the boss intake offers max effort for "qualifying laps", which i have found out is exactly what time trials has been like.

i am a convert! rpm is king! can't wait to see what personal best i can come up with once 5th gear is restored!

just a note: if i was stuck with 7500rpm, as a lot of you hold to (whether by stock tune limits or mental barrier), the results would not have been as glorious. the magic is at 8000rpm, my friends!
 
And if you're going to 8,000 you might want to look at the Cobra Jet intake. I think the improvements will be similar. On paper it won't look that great but the high RPM's is where you'll see the difference. Steve Espo where are you?
 

pufferfish

Supporting Vendor
1,094
66
Maryland
i am at the top of my hp/lb ratio for TT3 already, so the cj power would have to be limited in the tune to not break out into TT2, where the competition gets REALLY stiff. believe me...and everyone i was chasing down in the back straight...i'm doing fine on hp 8)

i meant to ask espo why he wasn't running the cj this past weekend, but forgot. whats the deal steve?
 
1,281
3
Tulsa, OK
I'm of the opposite mindset as you, but if the boss intake works on your setup then more power to you! Literally...

I'm working with a regular '12 GT engine and I had the boss intake on the car for quite some time. Car seemed to pull just fine all the way up to 7500+ (scary, I know) but on the dyno I wasn't making any additional power past 6500, which is where the stock intake falls off. So in my case it wasn't worth the low/midrange torque loss to use the boss intake when I wasn't making any more power up top than a stock intake. Sure I could rev higher, but what is the point if the power isn't there? I'm sure all setups are different but in my case the boss intake was not the answer.
 

Grant 302

basic and well known psychic
Glad you finally have seen the light! 8) I followed your Boss/GT intake thread on SVTP for a while before chiming in...but I've seen the difference driving the cars back to back and when I've been on track with the GT and other Bosses at Chuckwalla and Auto Club. I remember closing in on a Boss coming through the last few turns at Chuckwalla, but once we got on the straight I quickly lost any advantage of corner exit speed and the Boss just gradually pulled away taking big 'leaps' when the GT would wheeze at the top of 3rd and 4th. The difference in power delivery was obvious. But that is comparing stock GT vs stock Boss engines and not just the intake like on your setup.
 

pufferfish

Supporting Vendor
1,094
66
Maryland
gt engines are certainly different in their airflow capabilities. i wouldn't spin a gt engine that high on a regular basis anyhow. the rods don't resist the high rpm stretch as well as the boss rods do and the valve springs are not up to the task for the long haul either.

i do see on my dyno graph that the hp levels of the gt and boss intakes are identical from 5800 to 6700, so if you are limiting yourself to 7000rpm, there is no benefit to the boss intake.

but, if your engine can take the rpm, there are benefits even if there is no more power to be made. the fact that the boss intake doesn't fall off a cliff, like the gt intake does, means the extra rpm is still useful for acceleration.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
3,752
1,222
Exp. Type
Time Attack
Exp. Level
10-20 Years
NY Metro
Glad to see that Steve P saw the light, GT intake is good but the Boss is better and the CJ is off the charts! If puffer has a 5th gear then he is running 2:07's!!!!!!
As for me I had been trying to find a persistent vacuum leak for 2 weeks that was causing 30% fuel trim surplus. After changing every hose on the engine and pulling the manifold I finally found a crack on the back of the plenum of my Boss mani. That was fixed with super glue and RTV. Ran the logs for Shaun at AED again and bingo he sent me a baseline CJ tune. Problem was I ran out of time., it was Tuesday and we were leaving Thursday morning and I still had to get my CF Driveshaft in, change pads and rotors, bolt on the slicks and load the trailer. Didn't want to mess up the intake install by rushing so I ran with the Boss at VIR. Will be doing the install and posting on it over the next week or so, we are away for a graduation this weekend so it might be next weekend before I have it in.
Steve
 

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