View Full Version : 275s in the rear??


Alberto v05
05-25-2012, 10:15 PM
So the ls1 4th gen Camaro really comes with 275s in the rear for stock tires is that true????

SSdreamz
05-25-2012, 10:18 PM
the SS does, its a 17 inch wheel with 275s, the Z28 comes with 16 inch wheels

Alberto v05
05-25-2012, 10:19 PM
But does the z28 come with 275s as well?

TransAmWS.6
05-25-2012, 10:19 PM
SS's, Firehawks and WS6's had 275's all around, Z28's, base T/A's and Formula's had 245's.

Alberto v05
05-25-2012, 10:26 PM
Okay thanks so the ss's firehawks and ws6's had 325 hp stock and the z28's and 310 hp stock right?

TransAmWS.6
05-25-2012, 10:30 PM
No, they are all underrated. All LS1 cars are in the 345-350 crank horsepower ballpark stock, give or take a few for the SS's, WS6's and Firehawks.

Alberto v05
05-25-2012, 10:39 PM
Oh what for reals i was told the ss' had 325 and the z28's had 310 that's why they have different tire sizes cause different hp but yea?

TransAmWS.6
05-25-2012, 10:43 PM
No, the wider tires are really for handling purposes

ULTIMATEORANGESS
05-25-2012, 10:51 PM
Oh what for reals i was told the ss' had 325 and the z28's had 310 that's why they have different tire sizes cause different hp but yea?

mine came with an slp cat back which and it was rated at 7 hp more.


for reals.

Starz T/A 17
05-25-2012, 11:23 PM
GM claimed that the "ram air" added 15 HP but it is basically just an appearance mod, and doesn't help unless your going in excess of 100+MPH. Although there were other options available on the SS and Firehawks such as SLP exhaust or a aftermarket lid that made up some of the higher HP packages offered.

mjs1012
05-26-2012, 07:42 AM
The SS/z28 are the same minus the hood/spoiler and a few extra things from slp like minor suspension upgrades.

StuntmanMike
05-27-2012, 06:02 PM
I believe the stock size for the non-SS/WS6 cars was 245/50/16 all around, on a 16 x 8 wheels.

Like said above, the SS or WS6/Firehawk cars came with 275/45/17 all around, on a 17x9" wheel.

LOL, I remember when I ordered a 275/45/17 after ruining a front tire with a sidewall puncture and had it deleivered to work. One of the import guys saw it, and was like "Damn, your car has some wide rear tires!!". I said, "Actually, this is one of the fronts". His jaw damn near hit the floor...it was priceless.

US_Army_Z28
05-27-2012, 10:32 PM
Ive got ss wheels on my z28 and have 275/45ZR17 on em all around. Love the way they feel and handle and yeah i agree the ram air really doesnt help hp any. I mean you have to think its like sayin an ss adds hp but unless its a 97 ss then the hood scoop isnt even functional its justt looks

bww3588
05-29-2012, 03:18 AM
Stock tire size on base ls1 cars is dependant on the speed limiter. Some were produced with a 108 mph speed limiter, and came with 235 55 16's. The cars with 162 mph limiters had 245 50's.

For reals...

S8ER95Z
05-30-2012, 12:06 PM
Stock tire size on base ls1 cars is dependant on the speed limiter. Some were produced with a 108 mph speed limiter, and came with 235 55 16's. The cars with 162 mph limiters had 245 50's.

Are you sure about the limiter thing? I'm trying to find the faq but I don't remember LS1 cars having a 108 limiter.

I see tons of numbers... 108/115/120 (which is it? lol) for 2.73 geared autos with 235s (non z rated)... still digging.

US_Army_Z28
05-30-2012, 02:19 PM
Ive never heard of an ls1 with a 108 limiter my 02 v6 firebird didnt even have a limiter that low. The size of the tire was a factory option. My 98 trans am when i was looking for tires it had two options the basline was the 235 and 255 was part of the performance package option. My trans am was completely factory and had the 235s on it from the factory and it didnt top out until the needle was buried so i doubt the limiter has anything to do with it and i highly doubt they ever put a 108 limiter on an ls1

216StealthSS
05-30-2012, 02:35 PM
My alero speed limits at 112! no way they limit a LS1 that low... my LS1, had the speedo buried and still never found when it stops ;) factory 3:23 and 275's, i think mine is broke anyway, one guy told me he would race me and beat me with his dodge dakota R/T, he claimed the LS1 was limited at 130mph i told him i needed a winter beater anyway so lets race... he never did.

for reals.

US_Army_Z28
05-30-2012, 02:41 PM
Yeah i forgot to mention the ss and ws6 with the 17" wheel option and have 275 from the factory. Shoulve remembbbered that considering i have ss wheels on my car

baalic
05-30-2012, 02:50 PM
Ive got ss wheels on my z28 and have 275/45ZR17 on em all around. Love the way they feel and handle and yeah i agree the ram air really doesnt help hp any. I mean you have to think its like sayin an ss adds hp but unless its a 97 ss then the hood scoop isnt even functional its justt looks

The ram air hoods on the 98+ are just as functional, if not more. They force air into our lids which at 85 mph or so almost acts like a FI car......if you consider like 1 psi a FI car....haha.

Also yes some ls1's came with factory v6 sized tires, "235's" and were limited. I forget the mph they were limited at but... That is true.

US_Army_Z28
05-30-2012, 03:02 PM
Well i read up on how they work and yea they may work a little and but i highly doubt they are more functional than the 97 ss was considering the air box and filter were directly underneath the scoop. But on the cars with v6 tires they still werent limited low. I had mine up to 150 and is was all factory with 235s from the factory so the 108 limiter i have to ssay is still completely untrue

bww3588
05-30-2012, 06:05 PM
They were not limited at a certain HP, it was 108 mph because that's all the tires were speed rated to.

baalic
05-30-2012, 08:47 PM
Well i read up on how they work and yea they may work a little and but i highly doubt they are more functional than the 97 ss was considering the air box and filter were directly underneath the scoop. But on the cars with v6 tires they still werent limited low. I had mine up to 150 and is was all factory with 235s from the factory so the 108 limiter i have to ssay is still completely untrue

Doubt all you want, my ws6, with a lid feeds air in almost a straight line into the tb, having to slightly change directions 1 time as it goes through the filter, not to mention people that change the setup slightly with a fipk or the slp ram air kit.

The ss has a lightly less desireable ram air setup but works in the same way.

They were not limited at a certain HP, it was 108 mph because that's all the tires were speed rated to.

My iphone sucks it was supposed to say mph..

US_Army_Z28
05-30-2012, 08:56 PM
Ok talking about the ss here it goes into the hood at the vent at the middle of the hood then flows in the opposite direction back towards the front of the car then changes direction again to go into the air box and not all of it is even for sure gonna moke it into the lid and go into the tb and youre gonna tell me thats more efficient than a setup where the filter and air box is directly behind the vent all the air goes straight into the box and is routed to the tb? Like i said doubt it. I agree the trans am has a good ram air setup and is actually functional especially withh a raptor or superhawk hood on it

And considering that the slp cai brings air in from under the car not the top

baalic
05-30-2012, 09:02 PM
There is a thread somewhere on here that someone posted of tgem
Doing a sealed box, plus a pretty ingenious free ram air mod, that arguably wasnt free more fabbed.

The air that goes into an ss hood HAS to go somewhere it doesnt just dissapear, and if you take the time to seal your lid, it has an almost FI charcteristic to it. Given your only good for a few hp, but there is a reason all the lt1 guys convert to ls1 style lids...

Also theres another kit, "looking for link" of a box that helps to further. Channel the factory ram air into the lid..

On the 97 it might as well be the old school breather on top of a carb
Intake like on old school motors. While its true it could have been a better design, its really more gimmick on any ram air unless your running some custom fi system that utilizes the holes in our hoods..

TransAmWS.6
05-30-2012, 09:09 PM
Ok talking about the ss here it goes into the hood at the vent at the middle of the hood then flows in the opposite direction back towards the front of the car then changes direction again to go into the air box and not all of it is even for sure gonna moke it into the lid and go into the tb and youre gonna tell me thats more efficient than a setup where the filter and air box is directly behind the vent all the air goes straight into the box and is routed to the tb? Like i said doubt it. I agree the trans am has a good ram air setup and is actually functional especially withh a raptor or superhawk hood on it

Neither 98-02 WS6's or SS's have actual functional "ram air", the airboxes are not even sealed, the LT1 WS6's/SS's however have functional ram air since the airboxes are sealed to the hood.

baalic
05-30-2012, 09:34 PM
Neither 98-02 WS6's or SS's have actual functional "ram air", the airboxes are not even sealed, the LT1 WS6's/SS's however have functional ram air since the airboxes are sealed to the hood.

I have to disagree sir. Besides a little duct tape will "seal" your lid....

US_Army_Z28
05-30-2012, 09:39 PM
But it doesnt seal to the hood like the 97 model did. It was a filter without a lid the sealed directly to the hood where the vent was and even in the numbers the 97 ss made 305hp while a 97 z28 made 275 you dont see that much of a gain between a 98 ss and a 98 z28

baalic
05-30-2012, 10:20 PM
Those were factory ratings?? I thought they were rated at 285hp starting since 96 when they went to a dual cat for obd II. Which since your wrong on base z28 hp numbers probably on ss model as well. But saying you got the ss hp right, thats a diff of 20 hp rating vs the 15 hp rating on the 98+, but the ss's and z28's still dyno the same.

I mean, I see the possible advantage, but I still feel the 98+ is a tad better, especially on the ws6's which only has a rain deflector for restriction whoch a lot remove.

US_Army_Z28
05-30-2012, 10:28 PM
Yeah they were factory ratings i looked up the 97 ss and the 97z28 factory specs but i couldve told you the 97 ss has 305 factory because my grandpa has one sitting in his garage that he bought straight off the show room floor in 97 and the car is all original with less the 3,000 miles on it and the window sticker says 305 but i do agree the ws6 setup is great i cant knock that but when it comes to the ss i feel 97 had the bbetter setup sealing the box to the hood i mean im not putting any of em down i have a 2000 z28 and my gramps has a 97 and 2012 and theyre all badass but ive always wished the 98-02 ss had a true ram air setup like 97 did

baalic
05-30-2012, 10:42 PM
Factory hp rating on 96/97 z28's was 285hp fwiw... Not 275

US_Army_Z28
05-30-2012, 10:47 PM
Yeah that was a typo i thought i had put 285

baalic
05-30-2012, 10:51 PM
We hijacked the f*ck out of this thread.

US_Army_Z28
05-30-2012, 11:01 PM
Yeah thats what i was just thinking about lol

spy2520
05-30-2012, 11:34 PM
come on guys. that ram air didnt do SHIT!~!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

US_Army_Z28
05-31-2012, 12:02 AM
Ok i gotta know how does ram air do nothing

spy2520
05-31-2012, 12:32 AM
measure vacuum at 100 mph at WOT and if you have boost, i will believe it does something. but if that gauge is at around 100 kPa then there lies your proof.
The engine is gonna suck air stronger than that hood/intake/lid is gonna try to push air.
line up an ss vs z28 or formula vs a WS6 and no car will have a specific advantage in the 1/4. obviously on the dyno airflow would be fairly equal either way so i wont argue that point.

I give you this, at 200mph that ws6 ram air might be worth a few HP. cant say for sure.
But from 0 to 162 where these cars are supposedly limited, that ram air aint gonna do shit. If it was everybody would have it on every car.

bww3588
05-31-2012, 03:15 AM
Holy hijack...

Just to bring the thread back some, the cars limited to 108 are few and far inbetween. There weren't that many for obvious reasons, but they are (were) out there.

Just remember how easy it is to raise the speed limiter. Just because some people haven't seen it doesn't mean it doesn't exist. It's the same principal as the CAGS. How many 6 speed cars do you see with it still enabled? Not very many and every 6 speed car had it factory.

I'd imagine the ls1 cars that did have the lower speed limiter have had them raised or removed totally.

Besides, the only 2 I have seen and driven were automatics, with the steel 2 piece driveshaft, v6 sized tires and 2.73's.

Not trying to start a war, just saying because you haven't seen it doesn't mean it doesn't exist.

I've never seen a 98+ trans am without t tops, but there were 3 made.

RPM WS6
05-31-2012, 04:11 AM
Neither 98-02 WS6's or SS's have actual functional "ram air", the airboxes are not even sealed

This is the correct answer. True ram air requires a sealed setup. Yes, you can seal the stock setup, but that's not how it came from the factory on the '98+ cars. Therefore in stock form, they don't have actual "ram air".

line up an ss vs z28 or formula vs a WS6 and no car will have a specific advantage in the 1/4. obviously on the dyno airflow would be fairly equal either way so i wont argue that point.

I give you this, at 200mph that ws6 ram air might be worth a few HP. cant say for sure.
But from 0 to 162 where these cars are supposedly limited, that ram air aint gonna do shit.

Agreed. In the 1/4 mile and/or at street speeds, the factory "ram air" setups in factory configuration is a gimick at best.

Holy hijack...

Just to bring the thread back some, the cars limited to 108 are few and far inbetween. There weren't that many for obvious reasons, but they are (were) out there.

Just remember how easy it is to raise the speed limiter. Just because some people haven't seen it doesn't mean it doesn't exist. It's the same principal as the CAGS. How many 6 speed cars do you see with it still enabled? Not very many and every 6 speed car had it factory.

I'd imagine the ls1 cars that did have the lower speed limiter have had them raised or removed totally.

Besides, the only 2 I have seen and driven were automatics, with the steel 2 piece driveshaft, v6 sized tires and 2.73's.

Not trying to start a war, just saying because you haven't seen it doesn't mean it doesn't exist.

:nod:

Yes, there were in fact V8s with lower speed limiters. This had nothing to do with gear nor driveshaft options though; it was entirely based on which tires the car came with.

FYI. I've had two 2.73/steel shaft cars that were both optioned with the Z-rated tires and had 162-163mph limiters stock.

oddwraith
05-31-2012, 05:01 AM
This is the correct answer. True ram air requires a sealed setup. Yes, you can seal the stock setup, but that's not how it came from the factory on the '98+ cars. Therefore in stock form, they don't have actual "ram air".



Agreed. In the 1/4 mile and/or at street speeds, the factory "ram air" setups in factory configuration is a gimick at best.



:nod:

Yes, there were in fact V8s with lower speed limiters. This had nothing to do with gear nor driveshaft options though; it was entirely based on which tires the car came with.

FYI. I've had two 2.73/steel shaft cars that were both optioned with the Z-rated tires and had 162-163mph limiters stock.
Yup all true! Only way a 98-02 ram air setup may help is by assisting in drawing in some cooler outside air at speed, but not enough to really "ram" any air. Maybe sealed but better off with a ftra or similar.

Its also true that speed limiters are subject to factory tire ratings. Guess they didn't just make you a mod because of your cool name lol :).

Pretty standard info but I remember asking about, and challenging these things myself.

bww3588
05-31-2012, 05:02 AM
Most definitely. I was just stating the ones I have seen/driven were bare bones, highway geared cars...just saying they are few and far in between.

It's a simple safety issue. The tires were not rated to run the same speeds as the z rated tires, hence the lower limiter.

I think it has been beaten to death and proven many times that the ram air options from the factory are more for looks than anything. You can clearly see in the design, gm designed it for looks, then made it "functional"

US_Army_Z28
05-31-2012, 02:14 PM
This is true for 98 and up but i stand by when i said the 97 ss setup was very much functional

RPM WS6
05-31-2012, 04:43 PM
Guess they didn't just make you a mod because of your cool name lol :)

Haha! :lol: