If they ever ship mine out, I will let you know. Also for what it is worth, I ran a 10.80 with ported 241 heads and 2.02 valves with a bad lifter on my 408. I was getting 4* of knock retard as well so you should definately be able to obtain your goal on motor. I am shooting for sub 10.50's on motor.

 

It has been proven over and over again that the AFR 225s make big power in 408s. 550 rwhp is a pretty common number. The ET 215s have proven themselves to be as good as the AFR 205s (or possibly even better) with smaller 346s. The problem I've been seeing with the bigger ET heads (240cc+) in 408s are that they're not putting out the power that supports their flow numbers. Could it be that the port velocity is too slow with a FAST intake? Could it be that all that flow becomes lazy when you stick a FAST intake in front of it?

If the AFR 225s make so much power with the FAST intake on 408s, then maybe the 240+ ETs are too big and maybe their ET 225s would actually be a better choice. Come on, let's be honest...the AFR 225s have made easy power on the 408s without resorting to custom intakes or whatnot. Perhaps some shops should try bolting up ET 215s or 225s to their 408 builds and see if they too make easy power. The FAST intake needs a high velocity flow. It just may be that a head with a smaller runner will work better.

 

I agree I would like to see what gtodougs car would do with the same setup but a et 225 head or even an afr225

 

Partick, your thinking is exactly what I was thinking. I think that the 240 head flows so much air, that it's logjamming in teh fast intake if that's even possible, and anythign less then a true dual 3 inch exhaust is probably a logjam too... that head probably woudl like a 14 to 1 compression motor that saw 8000 rpm, because I think that's what it's gonna take to really use teh max potential of those heads. I'm not even coming close to that. I am very seriosly thinking about putting in an order for a set of ET 225's right now to try on my 402, see what happens. The only thign that's holding me back is the cam slelection, will the same cam work with teh ET and the AFR 225 head? If I knew that, I'd be calling someone and ordering the ET's right now and would be the guy to try it, it's looking like the end of May I'll have the $ to get my shop on building the 402 shortblock, I'm hoping to have it up and running by sometime in august. I'm sure I wouldn be the first person to do it, I'm hoping someone does it soon to see what happens. Hell, I'd like to see Tony flow a set of the 225's to see how they compare to the afr 225, that alone would give all of us a really good idea as to the possible results.

Now, another good question while we're at it, a cam for my 402, I'm thinking somethign like a 242/248 with 620 intake, 640 exhaust lift, 113 lsa or so, rest of teh cam spec's I'm not sure about, probably keep the icl at 108 or so. I think it's pretty good sized for a 11.5 to 1 402 CI motor, I think that my 1 3/4 qtp headers and catted Y are gonna hurt me a little on the top end power, but will help teh low end tq, probably get my heavy *** car moving a little easier.. not that it's gona need a ton down low with a 4500 converter and th400 with 4.10 gears... but it may still help. I'm probably initially gonna be at or over 3800 with teh addition of the iron block and my 275 lb ***... car was 3700 last year with me in it, I'm guessing about 30 to 50 lbs has come out since then, but there's 100 going back in with the motor swap, so it's gonna be close to 3800 again

just about time to start gutting stuff LOL, all the motor in the world won't do any good when the car's the most portly in the land

 

Typically, you advance a cam that's too big and retard a cam that's too small. If you choose your cam carefully, you will not need much if any advance. 5 degrees of advance on your cam is going to severely exhaust-bias your cam and it will run out of breath too soon. Ideally, you want to choose your intake valve closing point to where it makes best power on a 408. From what I've seen, that means it should be around 48-50 degree ABDC IVC to work best with the FAST intake. Anything later than that will peak later than the FAST intake is trying to force.

The duration is going to be around 8 degrees bigger than what works with a 346. If a 234/242 G5X-3 works great in a 346, then a 242/250 would be close to equivalent in a 408. Too often though, I see mistakes being made by running too wide of an LSA in these larger motors. Truthfully, to get the DCR up into the 8.5-9.0 level, it's better to narrow the LSAs some and not advance the cams so much. This will center the overlap closer to TDC and will allow the motors to rev better past peak hp. An ideal street/strip 408 cam in my view would be something with LSK lobes like a 243/251 .653/.660 110LSA (+2). You get an IVC under 50 degrees ABDC and your overlap is exactly centered over TDC.

 

What you just said, is why I'll leave teh cam to one of teh experts LOL. I understand what the duration, overlap and lift stuff does, but all that oter stuff is where you lose me. I've read teh JRP giude several times, and my brain usually hurts before I get 3/4 the way thru it LOL. What you are saying is probably correct.. and is most likly what I"ll end up with. The 660 lift though.... what springs are up to that task

 

I can only assume that if you go up in cubes, that you would want to enlarge the duration and maybe widen the LSA a bit, but if you added a much better intake, you may want to keep the duration/LSA the same and let the abundant intake charge do the work. Basically, the 408/FAST has the 243/251/110+2, but I was seriouslly thinking about putting something very similar in my 454/Harrop set-up. (243/253/110+2) Since the car can now move more intake air then before, it only makes sense to open up the split some. This will give me 11:8 SCR and 8.75 DCR. That's how it's looking in my mind anyway....

 

Increasing cubes requires increased duration, but doesn't necessarily mean widening the LSA too. Adding longer stroke usually means a lower rod/stroke ratio, which typically likes a cam with a narrower LSA. This is because the piston will have less dwell time at TDC and will act like it has less overlap. Narrowing the LSA some puts the overlap back where it wants it.

 

I'm running a cam that has .660" lift on the intake side. Cary set up my ETP 245's with the PSI spring upgrade. He said it should be good enough for anything up to .700" of valve lift.

 

That's good to know. Whateer I end up goign with, I'll have to have the spring up grade done. How much lift can you run before the lenth of the valve becomes an issue?

 

My engine build sheet states I have .130" PTV clearance on both intake and exhaust valves and .100" before coil bind.