Since deciding on a 408 buildup, I am having trouble deciding on the parts. I plan on going with a cast crank, so as silly as this sounds, I dont want to make much more than 500rwhp. That said, I dont think my original head choice of TFS Twisted Wedge is going to flow what I need. I am now looking at Victor Jr heads. I figure I may as well match that with a Victor Jr intake...I will likely run a 750 Holley vacuum secondary, and a relatively aggressive hydro roller cam. I dont want to have to spin this thing to the moon, but I do understand that the Victor Jr stuff wont wake up until around 4000. This car is going to be a street driven semi-daily driver. Should I just stick with the TFS heads to detune the car a little and move the power band back down to more streetable RPMs? Or should I go balls to the wall and build a high-rev beast? PS, the car will be backed by a 5-speed, so its not like I will have to worry about a super high stall converter cooking on highway stretches. Opinions and more importantly, experience with similar combos is appreciated. TIA
Some really good advice I got in the past: An engine over 400 cubes will make torque, no doubt, so there is no good reason to run a dual plane. Cubes don't need a torque bandaid. So I whole heartedly agree with your choice of intake. I also think you are worring a little about the head size... Personally I would run AFR 205s over VicJR in a heartbeat. Just my opinion. Even AFR 185s would be decent if you don't want to risk port velocity. On that note, a Torker intake would be a good hedge on torque if you ran the 205s. This intake is also very good for hood clearance compared to the VicJR. You don't really want to make a 408 into a screamer from just about any standpoint. You will compromise durability with the long stroke, you will turn a fuel sucking engine into a complete pig, you could overpower the 5 speed tranny, etc... I am thinking about the same sort of combo for my 75: 408 (maybe 393 if money is tight) Torker intake (hood clearance and good velocity for street) 205 AFRs (awesome port effieciency... not just size) 750 Holley Probably C4 with 3k stall. (I am getting lazy... and my 4 speed is going into the 72) Then a fairly hairy solid roller cam, between 248-252 @ .050" with single pattern on 110 LC. (Solid rollers have the broadest power range of any cam, and I like the idea of a very flat curve. Have your cake (torque) and eat it too (hi-rpm power). My .02 Dave
Thanks for the info Dave. I wonder if I could get away with a solid roller on the street? I worry more about valve springs and oiling than adjusting lash. With that said, how often would I have to adjust lash on a daily driver? Im going to look into the torker intake and the AFRs, but the AFR heads have junk springs unless you pay $200 to upgrade them. They charge such a premium over similar heads, it seems like they would come with kick ass springs.
Yeah, the AFRs are high, but their flow effieciency is too. Something like 70% on both sides, compared to 55-60% on most others. I have never run a solid roller. I would like to. I do know that they are unforgiving if you don't set them up right. Something breaks and there is no cushion at all for other parts. I wouldn't run a solid anything in a daily driver. I missed that part. You are better off with hydraulic roller for that, I know that much. Dave
My choice? 6.25" rods, SRP pistons and a cam with around 250 or so duration...hydraulic roller would be fine, though not optimal. They're usually "done" by 6500 or thereabouts by design, unless it's got a rev kit. 6500 with a 408, assuming you're making power up that high, you'll hit your 500 HP goal and then some. VJ intake is fine...yes, they're designed for a 351" engine, put a 4" stroke crank in there and the torque will be fine. You "might" have more bottom end with a dual plane or a Torker...but both of those will choke above 5000. AFR or Edelbrock? Well lessee.......the 205's flow like gangbusters and make upwards of 700 HP on a good well though-out combo. The VJ's are capable of around 600 HP....but about $1000 less. Your choice. The 750 carb will be a little small....but useable. I'd use an 850. You already know my combo. Simple, easy to build, makes plenty of power. Best of all, it didnt' cost me $10,000 to build..in fact, if I had to duplicate it, the long block would most likely run me about $2000. On another note, I did see a guy a few weeks ago with almost exactly the same combo as I had, but in a '88 Mustang tube chassis car....with the Chapman/Victor Jr heads. Went 5.60's in the 1/8 at 122.
With 4" of crank spinning in there, I don't think I would want it running over 6k. That is a lot of weight tossin' around in there, and piston speed will very high. Mavman: What is your combo? Dave
dont worry, it'll have bottom end. go victor jr; torkers arent much to talk about. if the jr seems to need help, try a 4 hole spacer under the carb. figure shifting a max of maybe 6000. that will make the shift actually about 62-6300 by the time you react to the shift lite/needle. if you use a valve train stud girdle valve adjust can be reduced greatly. going with a small roller will let you use the 125 dollar springs instead of the 300 dollar ones that big rollers need. i have a cut down cast crank in mine that has a few hundred runs on it, thru the traps at 6500 with no problems. changed bearings twice, but that is mostly due to the alcohol which can pound the bearings some. just put good axles in the car, cause with sticky tires you'll need them. have fun. mine computes to a little over 600 fhp. as i said no crank problems.
I probably will end up going with the victor jr heads due to the cost. Its obvious they will make the power I want for less money than the AFRs. Mavman, where did you get your rotating assembly parts if you dont mind me asking.
My 347 w/ vic Jr. heads went a 7.20 in the 1/8th with a .544 I/.573E hydraulic roller cam w/ 10.5:1 compression. I don't think you'll have a problem making the power that you want to make with the 408W.
My goal is to run a 6.99 in the 1/8. Think its possible with the Victor headed combo and a decent cam? Oh, and stock suspension?
Cast Scat 9000 crank, Eagle H beam rods, and Mahle forged flat tops. Cam Research camshaft around .700" lift and 274 duration @ .050. I shift anywhere from 7000 to 7900 depending on a few variables. Victor Jr heads untouched by a grinder, victor jr intake and Ron's flying toilet alcohol injector. I got the rotating/reciprocating parts from about 20 different places. Cnc-motorsports was one of the main suppliers (crank, rods), pistons from local speed shop, bearings from Autozone (of all places LOL) Head and intake gaskets from another speed shop. Machine work and balancing done at a shop about 100 miles from here. The same shop has my spare engine, and has had it for about 2 months now...Eagle 4340 crank & 6.200" Eagle 4340 rods...C9 block...JE flat tops, going with a zero balance on this one. Ran best times last weekend. 7.91 in the 1000' 126 mph+, 6.08 in the 1/8 at a tick under 114. 1.28 60'. All in a 2500 lb (I think LOL) all steel Maverick. I was not expecting to run quite that fast...I just wanted a motor that was going to run about the same as the old 357w I had..but the 357 had 14:1 compression and ran 6.40's all day. On another note, we ran the "big" race yesterday. Supposed to pay out $1500/win I believe...went out in the 6th round (red light) but I was suprised I went that far (felt like crap all day). $40 to the loser of the 6th round...dang you'd figure there'd be at least $100. At the end of the day, I was logging timeslips. 1/8 mile times were at worst a 6.188, best 6.179. 60' times were best 1.328 worst 1.332. Kinda hard to dial in when it runs that far off. BTW, I also recorded my very first perfect run this year in the same motor/car. Dialed 8.08. .5000 reaction, ran 8.0800 but I was off the throttle at 118 mph. Now, back to the shift points. I said 7000-7900...depending. For instance, if I leave the starting line and I feel the rear move around from tire spin or shake, I will shift a little late to help the ET a little. I normally shift at 7000. If I shift at 7900, it will pick up about .04 in the 1000'....but .04 second is not worth tearing up a motor, thats why I don't wing it up there all the time. Plus it leaves me a little leeway in case the track goes to hell.
I run a 408w in my cougar. DSS shortblock,make sure you run H beam rods and forged crank. engine has vic jr heads ported by bennett racing,comp solid roller 688 lift,264,268 dur at .050. ,vic jr intake, My cougar has ran 10.30's at a weight of 3200 lbs. This engine relies on torque,shift at 6200,hits the beams at 6700. Its a very simple combo, but if it did it again,I would go with the afr 205's
My 331 engine is "supposed" to have a power range from 5500 to 8000 rpm, but it sure runs good from 2000-6000 rpm too. I have Vic Jr. intake and AFR 205's (which are big for a 331) and haven't even revved it over 6.3K yet, but it ran fairly good my first time out. BTW, the AFR 205's come with better springs than the 185's and would probably handle your hydraulic or solid "street" cam fine. Good springs become more important when you get into higher rpms. From what I've read in various other places, for your cubes, the AFR 205 is a great head right out of the box. I like AFR 205's and a Solid Street Roller cam for your application.
Hey, I can only say one thing I got a buddy who has like a 88-90 2dr crown vic and he built a 408 stroker, this car is still like the day it came off the assembly line, no weight reduction, and still a column shift and he runs low 12's and is planning on high 11's next summer. And remember I am not exactly lying when I say its twice the car a mav is. (2500 lbs-2700 compared to 4000lbs)
