Are high 12's possable with a LT4 Hot Cam, HSR, and Pro Lighting 180 heads on a stock short block(350) in a 91 Z ? The car does allready have headers, exhaust and a mild stall. What do you guys think?

 

If properly assembled with some PROM tuning you should see mid 12s all day long, with traction.

 

He will get a new chip made for the setup. He also has 3.73 gears that have to be installed yet.

 

depending on your altitude 12s are definately attainable,you will benefit from a 2600 stall and be sure to use the 1.6 rockers they unleash that extra bit of hp & tq.... that cam also responds very well to a shot of dope...N2O that is.....

 

That's the EXACT combo I'm putting together, so I'd like to hear some opinions as well. Mines on a 92 Z, though .

Anybody have experience with this combo?

 

No experience with it, but I think it should absolutely run 12's, just how deep into the 12's will depend on traction, tuning, complimentary parts, etc. I'd consider a slightly larger cam though with the HSR and those heads, something in the 224-230 duration range, assuming a 350 cid motor.

 

Is there a cam like you describe that won't hurt streetability much? I don't know much about cams.

 

What do you consider streetability? Obviously a 224/230 will have a little less vacuum than the LT4 hotcam, but I personally wouldn't run any smaller than that w/ the HSR. My setup is going to be TFS 23* heads, 227/233 .560 .569 112 LSA CMotorsports cam, LT1 intake, and 58 mm TB...

I have a friend who is running a 224/230 cam in his LT1 car w/ ported heads and says that cam is just as streetable as his 210/220 was before this one. It all depends on what you are looking for out of the car.

 

I had first thought of going with the 224/230, but some people said it may be too much for a daily driver. I rather error on the side of too small rather than too big.

 

I don't know why people say that is so big. People will tell you all day long that it has less low end torque, which is true given the bigger duration, but it doesn't make it any less drivable. My friends LT1 car w/ the 224/230 has more then enough low end torque to drive the car everyday. More then enough torque to gently touch the throttle and pass trucks on the interstate. He only has to spin it to 6100 rpm, and loves the way it drives.

He is the king of conservative and went to small w/ the 210/220 he had even though the car did run 12s. He thought that the 224/230 might be to big, but went with it and loves it. He noticed no real drivability affects from the swap. Yes it does have to idle at a higher RPM now due to the duration... It probably does need a converter... But why if you are trying to get a 12 second daily driven car would you skimp on the cam?

 

I have a 219/219, and it is VERY mild. I think I erred too much on the side of caution with my setup. I have a friend w/ a 239/239 cam, but it's in a 406 w/ LT1 intake. That car is daily drivable.

If you want to err on the side of caution, I'd get a 224/224-230 cam. It should be mild enough for a daily driver and work w/ the HSR better.

 

Well isn't there some sort of electronic vacuum canister or something similar that can be incorporated to provide vacuum for brakes, cruise control, etc?

Also, you've mentioned about the loss of low-end torque with using an HSR and a 224/230 type cam. How dramatic would that loss be? I really like the low end that comes with the stock setup, but I can deal with giving up a little torque. I mean, it's not like I'd lose enough to not even break the tires loose, right?

 

No you would still have enough to break the tires loose trust me!!! Personally low end torque is overrated. Torque is great down low for the initial feeling yes, but too much too low is just plain stupid. If you end up having more torque than traction, whats the use? You give up "low end torque" because w/ the HSR and the larger duration cams you move the torque up in the powerband. Thus giving you more top end HP. This is simply because TQ= (torque *hp)/5252. As far as moving a car down the track, having 350 ft/lbs at 4000 rpm will move you down the track faster than having 400 ft/lbs at 3000 rpm, while at the same time giving you more top end HP. Its useless for track purposes to have the 400 ft/lbs at 2500 rpm, because on the track you would only see 2500 RPM once: when you leave the line!!!

 

Well I guess what I'm asking is....like what would the difference be? For example, I'm guessing that the 350 max torque is in the low range for an L98, so what would you estimate the torque to be using an HSR and a cam like we're talking about?

The honest reason I ask is because this will be a primarily street-driven car, so I'd still like to retain that serious kick-in-the-*** feel off the line. But I also want to the car to be faster, period, so if I have to sacrifice some of that, its fine, I'd just like to hear an estimate of how much, ya know?

Thanks.

 

Estimating has a lot of variables. Like cylinder heads and such. My buddy put down to 380 rwtq when he dynoed w/ the 224/230 on a LT1. That was closer to 3500 RPM if I am thinking right. Its still going to have plenty of LOW END torque for you. $.02

 

What's the difference in LSA mean, specifically? Like with the same duration and lift, what would be the effect of having 110 versus 112 versus 114 LSA?

 

K, I've done what I should have in the first place and ran a search.....seems like I'll be going with the 112 LSA.

 

Digging it up, I know, but I'm still ambivalent on a cam choice.

What would the prom tuning be like for a 224/230 like compared to the LT4HC?

Also, I can't keep myself from worrying about the low end stuff - I won't be able to afford anything more than my stock converter, trans, and 2.77 rear for a while, and I have a feeling that anything bigger than the HC will be unusable for now.

Anybody else been in a similar situation and have to use stock converter and rear for a while with such a cam?

 

Either way you are gonna have to tune it to get what you want. Being that almost everything will need to be changed then it will take no more effort to tune the 224/230 than to tune the LT4 hotcam.