kagato

I know you can expect about 15 HP out of a LS6 intake on a stock LS1 but what kind of gains would it give on a head, cam full exhaust car?

I am doing a head/cam install right now and am running out of money on the reassembly and considering keeping the LS1 intake, I have PRC stage 1 LS6 heads, 224 .581 on a 114 cam and ARH header/y pipe, magnaflow catback. Would a loss of 25 HP be safe to say?

Also how far off would my tune be if I did my tuning now with the H/C exhaust then did the intake in the future and left the tune alone?

cowboysfan

you will need a tune with H/C swap.... dont want to run rich or lean. gains with H/C I would guess about 80hp to 100hp gain after your tune.

Greekey

iTrader: (3)

You ready for it? Keeping an ls1 intake on that combo will be a restrictor on air getting in. Are you running out of money and getting anxious to get it back together? Or just running out of money? You can find a used ls6 in the classifieds almost daily for around 300.00.

BOBS99SS

iTrader: (2)

Agree man you will be losing a lot more than 15 imo,trust me its worth it to wait to have it on there,

kagato

Cowboys: I know I need a tune with H/C and 100 gain is a fair guess but reread my question. looking for intake only gains with other mods listed.

Greekey and Bob: Kinda both reasons, yeah I know its a big restriction with H/C that's why I figured more of a loss than 15 HP just trying to get an idea of how much to decide if its worth delaying getting it running again! How about the tune? Is it a mistake to dyno tune with H/C/E then do the intake later and not retune!

CRAZZ28

iTrader: (13)

Yes, that would be a mistake. It will need retuned if you add the ls6 later.

BOBS99SS

iTrader: (2)

Nothing a few adjustments on hp tuners couldn't fix,but it would just be better to have the intake on there for the dyno tune,the reason I say more than 15 is because you will lose threw your entire powerband ,the ls1 intake just can't keep up,if you do leave the ls1 on then make the switch it will be a world apart from the ls1,you should also look into injectors also,

BOBS99SS

iTrader: (2)

You have all ready made it this far ,with the heads and cam,just save up a lil more and you can get one for a lil over 300 on here all day,it will save you money to wait ,figure your gonna have to pay someone to tweek your tune anyway after the ls6,

trans_am7935

iTrader: (15)

usually a good dyno shop will do a retune for a few buck (like 50 or so) or a little more, my buddy got a retune for free after he went up to a FAST 90/90 combo

bayer-z28

iTrader: (14)

I ran 336/346 on bolt ons with an LS1 intake. I pulled 414/372 with a cam, ported LS6 heads and an LS6 intake with a ported TB. Needs a retune, but I'm doing a 102 swap now.

kagato

Thinking you guys are right, just save some more and do all before the tune. Especially since my tuner will charge the full 600+ bucks if I do another tune with intake alone. Shouldn't my stock 98 injectors be enough for my setup? Whats your cam specs Bayer? 6spd ?
whats everyone's guess at the wheels (Mustang and dynojet) for my setup. head, cam and exhaust listed the LS6 intake, lid, FTRA, ported TB through a 6sp and tuned?

BOBS99SS

iTrader: (2)

Than your tuner is a dick and I would take my car somewhere else because that's such BS,my cam only car had my injectors almost maxed out at 5900 I think,was something like 96% so I would say you would need injectors also,which you can also get pretty cheap in the parts section,mustangs are a lot lower than most dynos but its all about how it runs,I could care less if I make 450 or 350,its just a number and means nothing at the track or on the street

1998flamedCamaro

iTrader: (4)

You are going to need bigger injectors and a walbro 255 as well.

bayer-z28

iTrader: (14)

Yeah, built T56, royal purple in everything except the engine. LS6 ported heads, Patriot gold dual springs, no UDP (yet), stock WP, SLP LT's and smashed Y-pipe, TSP rumbler cat back (Those LT's aren't that great, I know. $$$ to replace w Kooks) Stock rear and stock 3.42 gears. Cam is a PatG Custom torquer cam @ 224/228 .637 .639 110*. The LT's are holding me back, the LS6 intake is gone and my injectors were pretty well maxxed at 87%.

Get some 42#ers. They should be good for ya. I got some from the classified here for a great price. I'd figure with yours (depending on the cam) about the same as what I was running... ~414/380 on a dynojet with better LT's on a small-ish cam. I pulled 402/382 on a Mustang dyno but at 4000ft LOWER altitude = running rich as hell.

And $600 for a tune is a RIP OFF! A dyno tune should be $400-$450. And keep an eye on the a/f mixture and make sure he gets it as close to to stoich as possible. (12-13.5) TSP left a nasty lean spike in my low RPM on initial throttle snap and killed my low end numbers because of it. It was nice to get the car tuned, but the more I read it and the more I learned, the more I didn't care for the work. The biggest thing is TELL them what your car is supposed to do (cam design) and tell them what you want. They are working for YOU, not the other way around. It's your car and you're paying them good money to do this.

BOBS99SS

iTrader: (2)

^ that's last part is really good advice

kagato

You guys pretty certain with my small cam I will still need injectors and pump possibly? I am about 4000 above sea level. If i need them wont I need to switch on the dyno? (heard you cant just switch injectors and have the car run without adjusting the pcm)
Yea I thought the price my tuner is charging is high but I don't think I have much of a choice, there are only a few dyno shops in my whole state and this is the only one that does GM cars. The shop said their tuner is flown in and I am paying for his tuning work and the rental fee of their dyno, he is supposedly a GM engineer for one of their performance divisions.
Bayer- what do you mean by tell them what my car is supposed to do?
I know my cam is supposed to be a good all around good street manners and emissions friendly cam but I don't know what kind of a curve I should be seeing!
thanks guys!

odarabla

iTrader: (1)

Save your money bro and try to get you a fast intake. It will yield the most gains and it's worth 15-25hp over the LS6 intake. I picked up 23hp just from changing from a LS6 intake to a ported fast 90mm intake.

bayer-z28

iTrader: (14)

^ Yeah.. If budget allows I would spring for the FAST. I woulda done it too.. Always wanted one.

Yeah.. If you can have your car towed to the tuner, do that, or else do the injector swap in their parking lot (LOL)... Or pay them to just swap injectors out real quick.

I hear ya about not having tuners around. I was at 4300ft when I did my heads and cam (Alamogordo NM) and drove it up to TSP, at 3400 ft (IIRC,) to have them tune it (6mo later.) They were the only reputable LS* tuner around that I trusted at the time. I was almost maxed on the injectors and TSP told me they were at 87% when I asked. (before a run) That was running on the LS6 intake and stock ported TB. So if you were to go the FAST route, you could definitely benefit from a bigger set of squirters. You won't need a pump. The stocker is good for a little while.

And as far as what the cam is supposed to do; Depends on who grinds it. If it's TSP most of those are peak power cams, Thunder Racing seems to make a lot of cams good for power "under the curve" as they call it. You can tell by the air fuel ratio. They should get it as close to stoich as possible (Optimum.) If there's a lean spike for more than 500 RPM, they should be able to tune that out if they are any good (VE Tables, IIRC.)

Take a look at my dyno graph. Look at the air fuel ratio at the bottom. That can be tuned out and they didn't bother. Just ask for the graphs after they are done with each pull. (I'm realizing more as I type this... I've got a tune coming up this spring and I don't feel like getting a half *** tune again.) The thing is, I didn't tell them that my cam is a low end torque cam, so they just tuned it for peak power. They only technically tuned it from 3500rpm to redline. Not good seeing as my LOW rpm is prolly out of whack.

Cams will act differently on different cars (Same with any other modification.) Intake setup, age of the engine, ring "health," coil temperatures, Heads and port work, and exhaust setup. A LOT of variables.. Even humidity. That's also why if you get it tuned at "X-Performance" and drive 20 miles down the road to "ZX-Performance" the readings will not be the same.. Prolly within 3-7hp differences that half of that is prolly dyno differences. Even sticky tires make a difference on what you pull (FWIH.)

MikeWS6

I would say a loss of 25-30 is a good estimate. Just grab a fast and be done with it.

kagato

Yeah a fast would be nice but its a stretch right now to even get the LS6 intake!
Thanks for all the help Bayer
I am not sure if the cam is from Comp, its not a tsp for sure. I got it from a friend that had it in his 02 Firehawk years ago. Could be a thunder grind, all I know is the stamping says 3722R/3722R HR 114+4 Y9173 and 287 I think.
I will have to try and spend some time in the tuning section to learn what to expect when the dyno time comes!