The large cam journal cam allows these LS1's to turn really high rpm without lifter float, also allows aggressive lobe profile without over accelerating the lifter.

The intake manifold seems tuned for range up to 6500 or so on the LS1 won't have problems of runners starving each other for air, since you only have 4 runners on each side of the plenum.

The pistons, and rod ratio will be overcome by aftermarket piston/rod required on the ford, and rod ratio really doesn't mean much on a street motor.

THe coil on cyllinder and crank fired ignition provide exactly precise ignition timing on a per cyllinder basis.

It all adds up.

 

Dont forget Chevys new firing order which breaks up cylinders near each other from firing in order and than having to share plenum gases. This is a big upgrade requiring crankshaft differences. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

 

BTW how high could 347 stroker ford rod to stroke ratio be when block deck height is short with longer stroke? LS1 has a 1.684 rod to stroke ratio, i dont think Ford stroker could reach that on 347"?

 

The rod ratio on the 347 strokers is not much different from the 422 strokers on this side of the fense. Like I said, rod ratio really doesn't make that much of a difference on a street motor, it is splitting hairs on a racemotor.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by erikd93lx:
<strong> The 4.6 was not actually developed to be a mustang motor at first. IIRC it was designed to be a motor for one of the lincoln luxury cars or a crown vic or something. And as far as the 5.4 in the cobra r, it was much more than a cowl hood. the 5.4 does not fit between the strut towers in the mustang because it is so wide. They had to do some major suspension mods to the mustang to get the 5.4 to fit. All I was saying, is that the 4.6 could be a little bit longer, and the bore could be bigger giving it more displacement. .02 </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">As far as the Cobra R...all it was the cowl hood for the intake, besides that no other mods are needed to fit a 5.4 in the engine bay of an SN-95 body style Mustang. A friend of mine in Vero Beach, FL and avid poster on Corral stuffed a naturally aspirated 5.4 Navi motor into his 96 Cobra. Used the stock k-member and motor mounts. Has A/C and P/S also. High compression, regrinded cams, short runner Navi. intake, ported heads, exhaust and all the bolt ons...436 rwhp and 380 rwtq on motor. And yes I agree that the 4.6 is need of a bigger bore. As far as Ford being behind in the N/A game from a modular standpoint....I tend to agree. Although there have been a couple of magazine articles and dyno runs online of stock 2000 R's dynoing anywhere from 355-375 to the wheels in stock trim. LS1/LS6 motor is a sweet motor. GM obviously did their homework on designing the heads for that motor. Ford just really need to get off of their asses and drop a big cubed modular in the Mustang. I was kinda disappointed the 03 Cobra was slapped with a roots blower. Great bolt on car no doubt but an N/A 5.4 would be nice. Modular prices are slowly starting to come down but the fact remains there a lot of owners who are just afraid to tear into these motors. Once people get over that fear, prices come down and the aftermarket gets on the band wagon, I see lots of good things happening for the modular scene.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 89foxpilot:
<strong> First off, lets compare apples to apples. There is no factory SBF head that will perform like the LS1/6 casting. No, not even the Cleveland 4v. So right off, one answer would be that no direct comparison is possible, or that in fact an equivalent factory Ford small block does not have the potential of an LS1.

Of course, we (I'm a mustang driver) have a huge aftermarket, and collectively many times the R&D time and money of the LS1...just the way it is...the motor has been around a lot longer. To say you can't make a Ford SB perform with good aftermarket parts as well as an LS1 is an exercise in ignorance. Most of you with your heads buried in LS1.tech all day would never know. Just for an example, an out of the box run of the mill Trick Flow twisted wedge head flows in the neighborhood of 240-250 cfm, with comparable low lift numbers to an LS1....not to mention this head will port about as well as an LS1 casting....and there are several SBF heads that perform better. (edelbrock victors, TFS high ports TFS R's, Canfields, and AFR's extensive lineup) Modern Ford HR cams use lobe profiles close to or as aggressive as LS1 grinds. The reasons you don't see a huge number of people making 400+ rwhp in a Ford are:

1. Most aftermarket intakes are the long runner variety (12-17") that are designed to boost torque for the majority of customers...IE those with 302s or 306s. There are not many good affordable EFI intakes suitable for big power on a stroker 331-347....or even windsor motors. Even the Holley, Edelbrock victor, and TFS R are the long runner style.

2. There are almost TOO MANY different parts to choose from for SBFs and mustangs. This makes it REALLY easy to mismatch a combo, trust me. You guys have maybe 15-20 cams that are really popular, and are proven, 1 intake manifold, and 2 basic castings on which to derive power. In summary, the stuff out there for LS1s is mostly REALLY good stuff....whereas alot of the Ford parts sold today are still 15 year old technology that people for some reason still are intent on using. This is why you guys are destroying alot of 347 mustangs out there with old GT40 or edelbrock heads, old performer intakes and "E" cams. Well, no ****, sherlock!

A combination that would rival or beat a cam/intake or H/C/I LS1/LS6 would be:

*A good 347 short block with higher compression pistons ~$1500-$3000

*AFR 185 or 205 out of the box heads ~ $1300-$1500

*spyder EFI or box upper intake ~$600-$1200

*custom cam from FTI, Hitech Mtrsprt, or Buddy Rawls ~$300

*1 3/4" LT headers ~$300
-of course more money on other small assorted parts-

Depending on how you cammed it and the compression, this motor could make 485+ fwhp on pump gas, and get by with just a computer tune and bigger injectors.

Yes, I know we have now spent more on this motor than would need be spent on a HCI Ls1, but then again we are using all aftermarket parts, and we didn't pay 20+ grand for the car to begin with, now did we? <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Oh, and for the guy saying Ford motors don't hold together....I've heard of a guy that made 400+ passes with a 250 wet shot on his STOCK 5.0 short block. This is an extreme example, of course, but I'd bet nobody has done this with one of your stock aluminum mills. You guys don't get forged pistons from the factory, either, do ya? <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

I love LS1 cars, the motors amaze me every time I see 1/4 mile times or dyno numbers, and my next car will be one, but don't think they are the end all of performance, and be careful who you listen to...alot of ignorance being thrown around in this thread.

<img border="0" alt="[chug]" title="" src="graemlins/gr_chug.gif" />
-Neil </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Great post! He summed it up perfectly and i have personally seen what a stock bottom ended 302 with a properly matched combo can do, it was kyle lewis's cobra, with a ed curtis (FTI) setup, AFR 165 heads and a FTI cam, and he was running door to door with me, and he was 44 cubic inches the underdog....mustangs can be made to haul some serious ***, and as he said, it's all about the right combo, WAY more parts out there for the sbf, properly matched, they can put some serious power to the ground...

nitin reddy
ws6luvr

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> As far as the Cobra R...all it was the cowl hood for the intake, besides that no other mods are needed to fit a 5.4 in the engine bay of an SN-95 body style Mustang. A friend of mine in Vero Beach, FL and avid poster on Corral stuffed a naturally aspirated 5.4 Navi motor into his 96 Cobra. Used the stock k-member and motor mounts. Has A/C and P/S also. High compression, regrinded cams, short runner Navi. intake, ported heads, exhaust and all the bolt ons...436 rwhp and 380 rwtq on motor. And yes I agree that the 4.6 is need of a bigger bore. As far as Ford being behind in the N/A game from a modular standpoint....I tend to agree. Although there have been a couple of magazine articles and dyno runs online of stock 2000 R's dynoing anywhere from 355-375 to the wheels in stock trim. LS1/LS6 motor is a sweet motor. GM obviously did their homework on designing the heads for that motor. Ford just really need to get off of their asses and drop a big cubed modular in the Mustang. I was kinda disappointed the 03 Cobra was slapped with a roots blower. Great bolt on car no doubt but an N/A 5.4 would be nice. Modular prices are slowly starting to come down but the fact remains there a lot of owners who are just afraid to tear into these motors. Once people get over that fear, prices come down and the aftermarket gets on the band wagon, I see lots of good things happening for the modular scene. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I could have sworn they did more to the cobra r to get the 5.4 to fit. I could be wrong though I guess(it would be a first though <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> ) Anyway, as far as the mod motors go, I think they will come along pretty good, they just need some time. My friend is building a stroked 4.6 which will be about 304-306 cubes when it is done. He's also getting alot of other stuff done(head work, custom cams, portmatched bullitt intake, etc), anyway, the cam grinder and engine builder both seem to think it will have about 450 crank hp with 11:1 CR. If he really gets that kind of power out of it, i will be seriously impressed, especially since he is leaving all the emmisions stuff on it except cats. It is a totally custom job, no one out there has anything like it, so we'll just have to wait and see. It should be an interesting project though.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by erikd93lx:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> As far as the Cobra R...all it was the cowl hood for the intake, besides that no other mods are needed to fit a 5.4 in the engine bay of an SN-95 body style Mustang. A friend of mine in Vero Beach, FL and avid poster on Corral stuffed a naturally aspirated 5.4 Navi motor into his 96 Cobra. Used the stock k-member and motor mounts. Has A/C and P/S also. High compression, regrinded cams, short runner Navi. intake, ported heads, exhaust and all the bolt ons...436 rwhp and 380 rwtq on motor. And yes I agree that the 4.6 is need of a bigger bore. As far as Ford being behind in the N/A game from a modular standpoint....I tend to agree. Although there have been a couple of magazine articles and dyno runs online of stock 2000 R's dynoing anywhere from 355-375 to the wheels in stock trim. LS1/LS6 motor is a sweet motor. GM obviously did their homework on designing the heads for that motor. Ford just really need to get off of their asses and drop a big cubed modular in the Mustang. I was kinda disappointed the 03 Cobra was slapped with a roots blower. Great bolt on car no doubt but an N/A 5.4 would be nice. Modular prices are slowly starting to come down but the fact remains there a lot of owners who are just afraid to tear into these motors. Once people get over that fear, prices come down and the aftermarket gets on the band wagon, I see lots of good things happening for the modular scene. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I could have sworn they did more to the cobra r to get the 5.4 to fit. I could be wrong though I guess(it would be a first though <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> ) Anyway, as far as the mod motors go, I think they will come along pretty good, they just need some time. My friend is building a stroked 4.6 which will be about 304-306 cubes when it is done. He's also getting alot of other stuff done(head work, custom cams, portmatched bullitt intake, etc), anyway, the cam grinder and engine builder both seem to think it will have about 450 crank hp with 11:1 CR. If he really gets that kind of power out of it, i will be seriously impressed, especially since he is leaving all the emmisions stuff on it except cats. It is a totally custom job, no one out there has anything like it, so we'll just have to wait and see. It should be an interesting project though. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yeah the mod stuff will catch on sooner or later. Mod Max xame out with stroker kits last year for the 4.6, bumps the cubes to 302. VT Engines in MI is now producing stroker kits for the modulars Sleeved block with a 3.7" bore yields 304-305 cubes...combine the sleeved block with the stroker...324 cubes. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> Darton came out with some new 3.8" sleeves now and deck extensions for the aluminum 4.6 block. Now if prices would just come down. <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 5-liter-eater:
<strong> well I could care less about the ford vs chevy pissing match but I am willing to put my stock cubed NA 2001 Z28 against any 347 na mustang. Im on the east coast, lets see how it goes, all in good fun of course, unless you beat me..then I will be forced to kill you so no one can know <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" /> Oh full interior cars only, none of this gutted POS crap. Daily driver on pump gas as well. Whos in <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" /> I am not that fast I just wanna race a mustang with 400 rwhp. LS1onderfull knows my car and will attest it has no blower, no nitrous, stock cubes. Full interior as well. I know of one 347 stroker in Mass but hes already been torn a knew one when I only had a cam and stock heads. He must have been untuned or something I guess, I think it was a Mike DEZ racing car or maybe a CE mustang cant remember. Whos game. Enough with numbers, lets see head on action. <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I will send this post to Michael, but just remember Mike races profesionally and if he brings a car he "WILL" be <img border="0" alt="[burn out]" title="" src="graemlins/gr_burnout.gif" /> <img border="0" alt="[driving]" title="" src="graemlins/gr_driving3.gif" /> driving it! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

I just had an idea sign up for this http://www.svtoa.org/home.htm?conten...dragdayreg.inc Mike Dez is co-sponsoring this, and U will have more than enuff stangs to race! <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by sscam68:
<strong>That 281 is working harder than a 346 is <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> What I am referring to is power per cube. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Isn't this something that ricers always say? <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" />

 

Like I said, if they say their motor is "smaller" than yours have them pop their hood and compare physical engine dimensions. The DOHC makes fora very large motor.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> Yeah the mod stuff will catch on sooner or later. Mod Max xame out with stroker kits last year for the 4.6, bumps the cubes to 302. VT Engines in MI is now producing stroker kits for the modulars Sleeved block with a 3.7" bore yields 304-305 cubes...combine the sleeved block with the stroker...324 cubes. [Smile] Darton came out with some new 3.8" sleeves now and deck extensions for the aluminum 4.6 block. Now if prices would just come down. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Supposedly, the "big bore" kit as it is called, isn't too good for street driveability. They say since the pistons are so close together, the motor makes some serious heat, which causes some problems for non-race motors. They also require the use of copper gaskets, this is all just what I hear though, no solid evidence just yet!

 

The LS1 engine is an outstanding motor from the factory, of that there is no doubt. The ls1/ls6 heads are better that any small block 302/351 head Ford ever made. However, a well put together 347 can make as much or more N/A than any current stock cubed LS1. There is just so many aftermarket parts available in the Ford market that it can be hard sometimes putting together the right combo. Recently AFM built a 470rwhp FI 347 w/a hyd. cam. In my opinion this motor could have put out more with a few different parts. They have built several 400rwhp 306's also.

Robert

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by erikd93lx:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> Yeah the mod stuff will catch on sooner or later. Mod Max xame out with stroker kits last year for the 4.6, bumps the cubes to 302. VT Engines in MI is now producing stroker kits for the modulars Sleeved block with a 3.7" bore yields 304-305 cubes...combine the sleeved block with the stroker...324 cubes. [Smile] Darton came out with some new 3.8" sleeves now and deck extensions for the aluminum 4.6 block. Now if prices would just come down. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Supposedly, the "big bore" kit as it is called, isn't too good for street driveability. They say since the pistons are so close together, the motor makes some serious heat, which causes some problems for non-race motors. They also require the use of copper gaskets, this is all just what I hear though, no solid evidence just yet! </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I have never heard of any of those problems before. The only know of 2 people that has ran a sleeved block for the street with copper gaskets over on corral.net. They both haven't had issues with their street driven cars. But then again I have no idea how much their cars are street driven.

<small>[ February 23, 2003, 06:49 PM: Message edited by: slobra281 ]</small>

 

Not to knock AFM, but have you noticed the rwtq on that combo? Think it was like 386, also have you noted where the 470rwhp was made? It was a very high RPM, something quite a bit over 7000 rpm.

The LS1's on this side ( cartek/lg ) are making this type of power just over 6000 rpm.

It helps if you are making over 420rwtq at 5200 RPM.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> I have never heard of any of those problems before. The only know of 2 people that has ran a sleeved block for the street with copper gaskets over on corral.net. They both haven't had issues with their street driven cars. But then again I have no idea how much their cars are street driven.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Like I said, all of what i heard about the big bore kits was heresay, so it could be false information. But I did look at the block, and it seems like the pistons are already close together, so I could see how it would get really hot if it got any closer. I dunno though, I guess once more people are running them we will find out eh?

 

what is the fastest ls1 n/a car?

the fastest n/a modular motor goes 9.40's from modular performance.

what is the fastest power adder ls1?

the fastest power adder modular i think runs 7.20's.

kind of seems like in an all out effort n/a or power adder the modular is better.but in a street strip type setup the ls1 is better.

 

HP-GURU, I'm not saying that AFM is the best engine builder or that this is the highest producing N/A 347, just pointing out one recent example. Also, the power is made in the upper RPM's for a reason, this is where a motor lives on the track and low end is made up for with lower gearing. If one wanted to make a 347 to make power in the lower rpms it can be done with a different selection of parts. But the motor with the higher power band and deeper gears, with all other things being equal, will be faster IMO.

Robert

 

roger- this point (well, one similar to it) was brought up in another thread awhile back... if we're comparing the ability of the motors, drag times are NOT a good way to do it. There are simply WAY too many variables.

Vehicle weight, suspension settings (as well as suspension design; I honestly believe the solid axle Mustang to have a superior drag-oriented rear suspension than the F-cars), transmission gearing, etc...

Like I said, too many variables. Additionally, the number of dedicated track-only LS1 F-cars pales in comparison the number of track-only Mustangs. I would say that the vast majority (I would guess 99%+) of the performance-oriented LS1 folks use their cars primarily on the street; so low-speed torque is a big factor vs. a track-only setup where low-speed torque doesn't really matter. Because of that, there really hasn't been all that much research done into dedicated, high RPM LS1's.

 

burnout..actually i think its the other way around.there seems to be a ton of development on the ls1's and not much but a few specialty shops for the modulars.once peaple stop getting scared of tearing into a 4valve you will see alot of very fast modulars around.they do have more potential just not the capability for cubic inches.