ok, kinda a stupid question, but here goes...

I have friends with LT1 and LS1 Z28s, that have heads and cam, and are producing anywhere from 390 to 420 rwhp ( NA ), with the right combo of parts...

then I have friends with 5.0 Mustangs, who also have heads and cam, and they seem to only produce 310 to 340 rwhp... ( NA )

why is that? is the 44cid difference enough to make that much less power? or our our engines just more advanced where we can get more out of them? Or have I just seen two bad examples of modifies 5.0s?

not trying to flame, just curious...

Alex

 

just a little piece of knowledge....STOCK ls1 heads flow better than most ported/aftermarket 5.0 heads <img src="gr_stretch.gif" border="0"> you should see the intake/exhaust ports on a 5.0 vs. the ports of an LS1 head...HUGE difference!

 

Part of it is the extra cubes, but a huge part of it is the airflow of the LS1/6 cylinder heads and intakes. The LS1/6 cylinder heads flow a lot of CFM stock, and flow really good values when ported. Well ported LS6 heads can flow over 300 CFM at 0.500 lift and over 330 CFM at 0.600 lift. Using the formula to estimate the maximum possible HP given peak cylinder head flow for a well-setup street car:
Max NA HP = 2.052 * Peak Head flow,
you can see that a head flowing 315 CFM could support up to around 630 flywheel HP. This is why some LS1 stroker motors are getting better than 600 HP NA at the flywheel from the ported heads.

 

SO it is possible with aggresive ported heads and intake, for a mustang to get anywhere near the power we get? without using a supercharger?

 

[quote]Originally posted by SuperZ28:
<strong>SO it is possible with aggresive ported heads and intake, for a mustang to get anywhere near the power we get? without using a supercharger?</strong><hr></blockquote>


N/A? NOPE. You will never see a 302 dyno 420 rwhp from motor alone. 5.0's are an excellent foundation for going fast with the right parts, but it will definately take a power adder to produce similar RWHP #'s to a well built heads/cam LS1.

 

I've owned 4 - 5.0's, 2 - LT1's & 1 - LS1. Any n/a 302 making 300-340 rwhp is doing great. A good 350 LT1 can make 370-400 rwhp and a 346 LS1 400-440 rwhp with heads and cam (so far). I believe the extra cubic inches help but so does the superior head design.

 

[quote]Originally posted by LEO:
<strong>I've owned 4 - 5.0's, 2 - LT1's & 1 - LS1. Any n/a 302 making 300-340 rwhp is doing great. A good 350 LT1 can make 370-400 rwhp and a 346 LS1 400-440 rwhp with heads and cam (so far). I believe the extra cubic inches help but so does the superior head design.</strong><hr></blockquote>

Leo is exactly right...

LT1's using LT4 head castings, and good grinds can make 370-420 rwhp with the correct combo's.

LS1's using LS6 head castings, good cam grinds, and all the other normal mods are in the 400-440 rwhp range.

When you compare flow #'s, valve sizing, etc.. on an LS1/LS6 head, there really isn't anything that comes close. Thumbs up GM <img src="gr_grin.gif" border="0">

 

""SO it is possible with aggresive ported heads and intake, for a mustang to get anywhere near the power we get? without using a supercharger?""

Well yes and no! As a recovering 5.0 enthusiast I have seen all that the 5.0 market has to offer and in general it's mostly all crap! The main culprit is lack of cubic inches and lack of decent intakes. It's sad but the stock LS1/6 intakes puts a severe *** whooping on the best 5.0 intakes out there except maybe the Victor 5.0 and TFS R. The problem is that the 5.0 long runner intakes are basically like Chevy's old TPI so when you install a REAL manifold you will lose substantial low end tq. This exaggerated low end tq curve feels great when putting around at low rpm but basically acts as a restrictor plate at higher rpm thus preventing any hp from even being made. What's stupid is that the average 5.0 dumbass doesn't want to lose any of their precious tq but then is surprised and confused as to why their ride never makes any serious power when something like the LTx or LSx engine do!

There's absolutely plenty of heads both worse and better than the LSx stuff for the Ford small block but unless you are carbureted you won't ever see the benefit of them. The runners on these street based manifolds are just severely too long. Some of you know Steve D of Houston Performance but he did a 347 with the Vic 5.0 and econo ported canfields which put 455 to the ground with a smaller solid roller cam like 4 years ago, also did a 510 RWHP convertible with a Victor intake converted to EFI. He went tens at over 126 and had no development in it at all. I have several friends that have big windsors with EFI converted carb mainfolds and they have made over 500 at the wheels as well from 400 cube motors.

The LSx is just a way better designed deal in stock form with correctly sized ports AND intake. People bitch about the intakes but they are actually very bad ***! These mountain motor LSxs probably do need a little more intake but in general the LS6 intake is VERY good!

 

Actually as far as the 5.0 based engine, I don't think it can compete with the bigger LSx but the larger Windsor can. The 5.0 is just too little even in stroked form. Mini Mee engines can get seriously hurt when playing with the bigguns!

 

[quote]disagree. There are plenty of them out there. All it takes is some compression, good porting, balancing, cam choice and tuning. Granted, 400rwhp 302's are not the norm for "bolt-on" engines, but it's certainly doable.<hr></blockquote>

Well, I said 420 rwhp, not 400 <img src="gr_images/icons/wink.gif" border="0"> . And, if you would, please correct me. Do you have ANY graphs of a N/A 302 dyno'ing 400 rwhp?? If so, I'd love to see it. No flames intended......


Josh

 

How old is the 5.0 as we commonly call it? 35 year old design? Is the BOSS 302 still the same basic engine as the 5.0 found in late model Ford Exploders, err I mean, Explorers?

While the LS1 went in production in 97, I guess development probably started in 94 or so?

J.

 

I know we're comparing the power potential of different engines (not cars) here, but keep in mind that a Fox-Body Mustang doesn't need to make quite as much power for identical acceleration (all else being equal, tranny, gears, traction, etc.). It weighs less. <img src="gr_sad.gif" border="0">

 

Damian, no flame intended here but there are many, many 5.0 Mustangs with stock displacement making over 420rwhp all motor. I will try and dig up a graph if I can, but i know for a fact they are out there and they do exist. The problem with 5.0 Mustangs making serious power with the stock bottom end is that the cylinder heads needed to flow the kind of air to support 420rwhp such as the AFR 185's will cause piston to valve clearance problems. Because of this the guys tend to use stuff like the TFS Twisted Wedge heads, the GT-40's, or the AFR 165's where they can use an off the shelf cam and the stock bottom end. If you were to take a stock block and build the rotating assembly right with notched pistons and went crazy with the top end you could make 420rwhp...although it would not be as easy as it would with an LS1. <img src="gr_images/icons/wink.gif" border="0">

 

The boss 302 only has the shortblock in common with the late model 5.0. The boss used cleveland style heads. As far as 302's making power, More than quite a few have obtained over 600 rwhp N/A. Hell, all the way back in 95 Powered by Ford's Super Trooper was turning 9.50's at 145 all with fuel injection, stock suspension and 10.5 tires.I believe it went as quick as 9.31 before it was stolen.Thats with 306 cubes, .030 over. Cory Roth just put together his new hot street 302 based motor. 359.7 cubes and HELLO, 783 hp at 8700 rpms. Thats N/A at the crank. His Eldebrock Victor heads flow 393 at .800 lift so The little ford still has much better heads available. The Brodix/Neal heads can flow over 400 cfm. But I will agree that the ls1 has the best stock component package for upgrading when you compare the 2. I'm looking for mid 10's this spring with just a heads/cam motor and who know's what with my 150 TNT shot. Next year its mid 9's or bust with 408 cubes.I would never dream of 11.40's with stock internals, N/A with any factory 5.0 offering. Thats one of the many reasons I switched to the ls1.

 

[quote]Originally posted by Y2K Blackbird:
<strong>
.....
Thats with 306 cubes, .030 over. Cory Roth just put together his new hot street 302 based motor. 359.7 cubes and HELLO, 783 hp at 8700 rpms. Thats N/A at the crank. His Eldebrock Victor heads flow 393 at .800 lift so The little ford still has much better heads available. The Brodix/Neal heads can flow over 400 cfm.
.....
</strong><hr></blockquote>

Whoa - the 393 CFM is great, but at 0.800 lift?? <img src="gr_eek2.gif" border="0">

What kind of flow can you get from these heads at sane (street) lift levels, say 0.600 or less? I am only wanting to know for curiosity's sake, since I am really low on the Ford knowledge.

Thanks.

 

You can still get 360 at .600. They just dont stall out, thats why they run .800+ lift cams. I know for a fact at .500 lift, Cory's heads are flowing 335I and 238E. Fox Lake does his heads(He is Fox Lake) and a good friend of mine runs a set of his Renegade heads so I know the info is good.He is looking for solid 9.20's this year in his 306 cube Renegade car. He runs Fox Lake Victor JR's. The ls1/ls6 is a much better street head due to the fact that it can flow some serious #'s and still has a huge amount of velocity. The above heads kinda lack that at "streetable" cam lifts and rpms. Velocity is key in a street motor.

 

I have friend that has a 1400 flywheel hp mustang. It is a 345in motor. Before the boost from the blower he made over 520hp to the wheels. Granted he has a $10,000 Motech computer and has spent over $85,000 in the motor but that is very nice N/A hp.

 

Damian says: "You will never see a 302 dyno 420 rwhp from motor alone."

I disagree. There are plenty of them out there. All it takes is some compression, good porting, balancing, cam choice and tuning. Granted, 400rwhp 302's are not the norm for "bolt-on" engines, but it's certainly doable.

That being said, an LS1 with the same mods as a 5.0L will just about always make more power due to better head design (MUCH higher timble, swirl inherent in the design), displacement, and compression. Just don't get caught in the trap of "there's no way a such and such motor could ever be as powerful as such and such."

I tune lots of 5.0L's, 4.6's, LTx's and LSx's here and have had more than a few engines surprise a lot of people.

 

5.0's take boost so well, why both going N/A? All things considered, you can make more power with a 5.0 for less money right now. Hopefully with more R&D the cost of LS1 stuff will come down, cause while I love my 393 rwhp, I sure wouldn't mind paying $2000 to get it, like 5.0 guys can.

 

its very hard to get 400 rwhp out of a 302 and still keep it as streetable as a 400 rwhp LS1........i'm sure they are quiet a few NMRA pure street 302s/306s that make 400+ rwhp but hardly any of them are cars u could drive around a significant distance without totally killing the valvetrain and seats.....i think its easier to make 400 rwhp with a 302/carb combo cause like racer7088 said the lack of decent EFI intakes

now 400 rwhp out of a 351w based motor is not too hard with a good Carb combo...(Vic jr intake,good heads,10:1 compressio or better,good size cam...) EFI is a little harder to do cause of intake selection...there are a few better intakes on the market now including the victor 5.8 and TFS....my car with a lo-po built 351w EFI should make in the area of 350 rwhp if i ever get it to run right...i've been tossing the idea around of going carb and building a mean azz 400 rwhp 6500 rpm beast to run with some of the head/cam LS1s...