1) Does it make sense to have a little more duration AND lift (I said a little) on the exhaust if not using the bottle or supercharging?

2) Does it affect the idle and if so what to expect?

Example Futral F-5: 224"/228" .588"/.576 (114 LSA)

Thanks

 

The short answer is generally speaking yes. Also generally speaking a little extra duration on the exhaust side has very little affect on idle characteristics. What really sets the idle characteristics is intake duration and LSA.

 

Those specs arent going to be a very choppy cam at all. Not to much duration and a big LSA. You'll know its there but it wont be to noticable (see: bit bigger than a good sleeper cam.)

 

I will be installing a cam simular to that only less lift soon

you WILL notice the idle.

 

You will hear that cam, but it won't be too nasty sounding, or cause idle issues. I have read the LS1s, especially stock, like more exhaust duration, and what I see at the dyno & track seems to back that up. And while a smalller lobe spearation (LSA) does give you more lope, it will also cause you idle tuning issues because it allows the exhaust gases to blow back into the intake at low rpms.

And that cam has as much lift as I would consider on a stock setup. 588 is a ton. I would highly suggest new roller rocker arms & chromoly pushrods. And if you are going to run that under John B's heads, ask him to clay the motor to make sure the valves clear the pistons. As I recall those heads have been milled. Meaning you get more compression, but you have to worry about clearance when you run a hi lift cam. And this one's getting up there.

PS If you are going to have John put this together, I'd ask him for a cam suggestion, since he knows how those heades perform.

 

Thanks for the info Mark. I didn't know those heads were milled. That may become an issue. I've been trading some emails with John, he's being very nice on answering my questions. He is suggesting the use of his B1 cam with his heads but lots of people have been telling me "it's too small, it's too small" but maybe they don't know (and I didn't know) that those heads have been milled.

I am salivating on that F-5-114 but I may have to rethink that. I'll have to bug John again...

BTW I'm ordering the QTP headers and Y-pipe this week YAY!!!

 

Freak, you might want to hold off on ordering your QTP combo till after tax time. QTP ALWAYS does a "tax return" GP along with many of the other sponsors. I was talking with Rokko the other day about it and he said that QTP usually takes 100+ dollars off during that GP.

 

I think the QTP group buy is going right now.

 

Anytime. There are millions of choices. Cams are like women, there is ALWAYS one that looks / sounds better. But what will serve you & your application best? I don't recall the specs on a B1, but John had good results with that setup. The cam & heads should match. So the B1 might be a good choice.

I wanted a cam with a bad-*** idle, and knew that meant it would be 'fun' to tune. And I wanted one that didn't have ramp rates that were too agressive (easy on the valve springs). I also wanted good mid range torque & fair top end hp. So I ended up with a GM Hot Cam & added 1.8 Harlan Sharp Rocker Arms to get me to the .555 lift I wanted.

I suggest anyone that doesn't know exactly what they want, do some research so you have some basic understanding of what things do. Then pick a reputable guy (like John or Ellis or Ryan or ____) to help you build your motor & just do what he says. Because if you start doing half of what one guys says, and half what some other guys says, it AINT gonna work. Most of us have a system / plan / grand design. And you need ALL the parts to make it work.

And no, I am not flipping you **** for asking these questions. Knowledge is good. But I am saying if you're going to let John do it with his heads, let him pick the cam. He knows his **** & has made good power with those heads.

And you will LOVE those headers!

 

Mark gives some good advice there, as usual... Definitely tap the knowledge we have floating around this area, and you picked a great guy to consult with in John B.

Cams are definitely like women... pick the right one, you'll be in heaven. Pick the wrong one, and well... lets just say you ain't gonna be a happy camper. I picked my cam because I wanted something that:

A) would provide good power in the upper rpms for drag racing without overpowering the car on the street in the low rpms,

B) wanted a big nasty sounding cam that had slower ramp rates so it would be easier on the valvetrain,

C) wanted something with plenty of lift for when I decide to go with some nice high flowing heads, and

D) was a split duration in case I wanted to run a decent shot of nitrous

A good idea is to make a list of all the things you want out of your car mods, what the most important features you like in a cammed car, and go from there. Make sure you pick a cam that you will not only be happy with now, but will also be a good match for any future mods.

 

Boyce and Rick, yeah I think this GP is going on right now, but it won't hurt to wait a little more to see what kind of promotions they come up with.

Mark, I agree with you. Although I do ask lots of questions I at the same time have a huge respect for all the guys who have "been there, done that, got the t-shirt" -- yes, that includes you -- so thanks again guys for all the info, that really helps on getting my homework done.

I'll wait and see what John has to say - either way I think the car is going to turn out awesome. MTI S2-R + cam + QTP + tune

 

Well One thing I can tell you is the cam I have here has less lift but same numbers and it had a rocking idle at

Ask Brian Smith. that is where it came from

 

The best advice i could give would be get the weight of your car, full head stats, and then call a cam manufacture and get one custom ground for your application, and to meet your goals. This is the only true why to get the performance you want for your car. I working on the details of a new cam as we speak, Think the t-rex is bad, just wait

 

You are over the top Jason....more than a t-rex....you kill me!

 

Jason is right. Custom Cams rock IF you know what you need.

For my next project we picked a custom cam from cam motion. Just a baby Hydraulic Roller 240/247 with .600ish lift

 

Well since i picked up my new truck yesterday, the car can start getting a little more wild, can we say solid roller baby

I think that a custom cam is defenatly the way to go, you just need to know exactly what your heads flow, what size valves, what comp ratio, how much your car weighs with you in it, what gears you have, and what your goals are.

One more thing and this is just my opinion. If you want a good racing cam, it's not going to be a nice street cam, and the same goes for a street cam, trying to race. Its real hard to get a cam that does both really well, so just make shure you know what you want to do with the car and stick with it.

 

Until someone makes a valve train that can handle extended RPM with a XER lobed cam I am going to be stuck using road racing stuff. Lots of duration, mediocre lift and a nice narrow LSA.

 

I want a nice street cam. I don't take the car to the track. Maybe in the distant future when the car won't be my daily driver anymore. But for now and for at least two years in the future, street cam.

 

Having said that tell us what you would like as far as Sound/Drivability/Cruise RPM things like that