I'll second all of your post, but especially this part. And 600 CFM carbs are for mild 302's, might as well suggest a 2 barrel as that. The stock carb probably flows more than that.

I think it's probably more of a timing issue coupled with too much intake volume and not enough velocity at low end further amplified by the restrictive exhaust flow.

There's more than one idiot involved here- the main one is the guy that claimed 500 HP with stock manifolds and created this nightmare.

 

Well I guess he could get a bigger carb but I was thinking in terms of the smaller cam and crappy ex. manifolds. I heard the engine builder actually suggested a 1,025cfm carb. Now thats just a little over the top there buddy. Are you sure you should be building engines for other people.

 

No, he doesn't need a bigger carb. He doesn't need a smaller carb. He doesn't need a different carb (unless there is something wrong with this one). He needs to tune this one (which he is) , but most of all he needs headers and if the humps weren't ground out of the exhaust port, that too or maybe just different heads.

Choking off the intake side is not the answer. With the big valves it will never balance out. If the builder had any competency at all, the OP would be begging for ways to tame the beast so he could hook up and not fry the tires at part throttle.

 

Heres the main things I think everyone would agree on:

1. Headers

2. A different machinist

3. Chassis tune then dyno

4. and most important, a lawsuit againts the builder.

 

right on doug and bb429 . I think this guy needs to get the builder to tell him exactly what he did. There are just too many unknowns that dont seem to add up. My 429 w/CJ heads D0-- started with 11 to 1 OEM. I put OEM (all that was available except for $$$$$$ flat top w/eyebrows) 460 TRW pistons. I have seen a chart somewhere that tells what CR you wind up with with different head/block/piston configurations. My comb was ~10-10 1/2 to one. I believe that all OEM 460 pistons were dished (20-22 cc's). If the builder put on small chamber,big valve heads, then the dish pistons would be 10 to1. If he went with dish and large chamber, then he is ~8.5 to 1. To wind up with 10.5 CR, the builder either cut the block or put specialty pistons in it or any number of combos. Next, on any street driven vehicle, 10 CR will be a bit of a PIA, unless you are strip only with good gas.

At this point, too many combo's are possible----much less if they were installed right, for my little mind---. I think he may be a bit of a victim himself (the owner). LOL

 

I have read through this thread several times lately, and keep thinking about the similar one that was brought to me a few years ago- '73 F250 4x4/ auto, 14x36 tires, "built to the max" 460 that ran more like a stock 360- certified bowser. I keep seeing stuff like "built to the limit", "cam timing advanced all the way", "golden brown" plugs, "hogged out", "floats the valves", and it all comes back to me. First thing, this is an engine for a 4x4 truck- not a car. Horsepower is nothing but a calculated number, useful for measuring work performed, but torque is the actual force that moves the vehicle. Sounds like the "builder" told you what you wanted to hear, 500 hp- when what you need is 500 ft.lbs, over a broad RPM range- the kind that will set you back in the seat when you hit it, anytime, anywhere. The other truck's story was real similar, local corner machine shop/wannabe speed shop, all the usual BS, hogged, polished, max, - huge cam with 9:1 compression, stock torque converter, Edelbrock/Carter carb, headers, wouldn't get out of it's own way, and had gone thru 3 quarts of oil during a 50 mile drive the last weekend Sounded wheezy, just not right. After the engine was assembled, it was taken to another old neighborhood good 'ol boy shop for installation, they got it running, but no huevos, back a couple times, and they couldn't get it any better, but were about 2K richer- so off to another GOB shop, another $500 later, still no huevos, "POS Ford" In the first place, again, they "built" it like a car engine (or at least thought they did)- just a bad combination from the start. Then errors were made installing it. After that, nobody could tune it. The oil consumption was a little puzzling at first, no oil on the plugs, but "golden brown" (too rich, and yes, they had "jetted" it to be that way). No oily carbon in the pipes, no appreciable blowby- but by then there was a little puddle on the floor of the shop. Traced it up to the left valve cover, pulled it off, and about 3" of the gasket was completely inside the valve cover, and TWO professional shops couldn't find it? While I'm in there around the valve cover, I notice a little carbon around the tops of the ports at the headers- so I pull the header off, and the fancy (expensive) copper header gaskets had been installed upside-down. If you've looked at regular 460 exhaust ports, you know that the bolt holes are far from centered vertically in the port, so about 3/8" of the port was blocked, and it was leaking the other way- nothing like a cork in an already poor port. Fixed that, and it started to sound like it had a pair- not very big, but a pair. So the carb- sorry, Edel fans, I'm not one, I know they can run good, but it's just way too easy to get good results with a Holley, easier to work on, etc.- and I didn't have a baseline to get back to before it was jetted, but I do know it's fat with the "golden brown" plugs- just a whisker of tan, thanks, but not pure white. So I pull a 600 vacuum carb off one of my Galaxies that I know is running good and dead stock (Holley, and Edelbrock for that matter, tend to know a little about their products, and the performance carbs are usually, if anything just a bit fat- not lean) Remember, this is a 4x4 engine, not a race car, and responsiveness and torque- sure a 780 will amke more top-end "horsepower"- but the 600 will eat it alive in the low and midrange, where a 4x4 engine lives- and actually get a little mileage... So now it's starting to run pretty good, has a little crack to it, so lets see about some timing- of course, the second shop had "re-curved" it including filing out the longest slot in the dizzy cam, and installing two "light" springs- so it had about 45 degrees, all in by about 2500... Get it back a little more reasonable, about 16 initial and 36 top, and add an early adjustable vac pot so it'll advance a bit under light load, and it's alive- still not all that it can be, because it's just not a good combo, especially for a 4x4- but at least it's doing what it can. So he comes over, and I torque it up against the brakes and smoke up both back tires in the shop- thought the old guy was gonna stroke out It's still running pretty good, but a shorter duration stick wold help it a lot, and he did buy a 600 from me- remember, this is a 4x4 engine, and we want torque, not 6000 RPM bench-racing "horsepower"

BTW, for quite a while, I ran one of my 427's in my old early '77 highrider F250 4x4's- it was an ex-race engine, but mild, stock flattops, put in a little short-duration .541 lift cam, stock set of CJ heads with just a good valve job and good springs, a Street Dominator and 600 Holley, headers, and Hemi Roadrunner mufflers. In real similar (mild) tune it had run 10.80@126 in a '62 Falcon. Had a lot of fun with it, made the whole truck shake back and forth about an inch at idle, and if you'd roll on the throttle about 35-40 mph in 3rd, it would just roast the 14-36.5's. I use to have a picture of it towing my boat when I did that, the sides of the boat were white with a Mercury outdrive- all you can see from the front of the back tires back is a big smoke cloud with a black propeller sticking out the end

 

With that piston choice, unless there was alot of decking done, compression may not be what it should be. 145 psi is very low for a 10:1 + compression engine. Stock the D3VE heads are 96-97 CC chambers, they are the large chamber low compression stuff.
The 88-93 engines run a similarly large chamber, and while the piston does only have a small dish, it runs a different pin height that pulls the piston about .015 further below the deck than most other 460 pistons.
With that combo, I'd expect no more than 9.2:1 out of your engine. I'd be very suspect of your machinist's claims.
I'm thinking you may have pretty large mismatch issues with some of the parts. And if you have valve float issues, something is definitely not right.
My current engine is running the smaller 256/262 Xtreme 4x4 grind, and, with stock valvesprings, I have no issues, even with it hard on the limiter at 5600. It's about 9.3:1, performer rpm, 750 edelbrock, mild porting on e6 heads(essentially the same as D3's,) with a stock 97 bottom end(bigger piston dish than the 88-93, but a taller pin height for the same effective CR.) I quite literally have $500 in the current engine build, and while I am giving up power without seriously ported heads, realistically I am making somewhere in the 325hp range which doesn't sound very impressive, but, the torque is right around 500 ft/lb at 4500, with it above 400 by 2000. Big fat low end torque is what it takes to make one of these trucks feel impressive. Even spinning 38.5 Boggers with 4.10's, mine is just that. No, it's not a huge lump of torque like my Cummins, if you're expecting that, you will never, ever get it, but it is a nice, broad big band of torque.

 

Well, I'm back guys. Haven't checked in for a while. I haven't been able to find the engine builder I'm not sure if he took a long vacation for the holidays or what, but i'm trying. I just did a mean burn out for my neighbor the other day, He was telling me how cool his chebby was so I went in front of his house and started the 34x1050s with the brake then at about 25 mph I let off the brake and floored it when the speedo hit 40 I clicked the c6 to 2nd and stayed on it and roasted the tires for about 75 yards without the brake, that is quite a bit of torque, but I still want more. Does anyone know anything about maddog headers, they look like L&Ls but have 2" tubes, and are cheaper. They look cool but I had never heard of them. The heads have the hump ground out on the exhaust side for those concerned. I think it needs more compression we did a test on my brothers 10:1 390 and it yielded some 153 or so max. It has a smaller cam but that is noticeably more than 145 on mine.

 

If you can not find the guy to argue his terrible engine knowledge, go your own way, just take it down and rebuild it yourself. Get some tools (borrow or buy) to measure engine parts. Blueprint your engine!

Fill us in on what the actual facts of the engine are, then start a fresh page on building power.

I will continue to watch your thread Warhorse.

 

Do you have the kickdown installed? This can actually rob a ton of horsepower in SOME cases. It can't hurt to check that and the amount of tranny fluid in the case. Also what gave my brother a problem before was a lack of fluid in the torque converter, it has to be filled up ALL THE WAY TO THE TOP or it can even cause it not to move.

-hope this is use full and you fix the problem.

 

IMO, for all out performance the Mad Dog headers would better than the L&L's but M.D. are thinner, not coated and have no rust out warranty. For a street engine the L&L's are probably a all around better header.

 

Well thanks for the advice. I found a guy close by that has had L&Ls and he said for a 4 wheeling truck and off road, go with the shortys because the fenderwell headers can get into the tires in extreme flexes with bigger tires, and since I do some pretty serious driving I don't want this being an issue. He had the L&L shortys and they looked pretty cool and easy to work on. I might go with them.

 

My two cents.

I kept reading that the cam was fully advanced...

To make a very long story short, my F150 with a 460 had a cam that was fully advanced (8 deg.) and ran like a turd. When I pulled it apart and put a degree wheel on it the cam was 19 deg. late!! I don't kow for sure which was wrong, the cam or the timing set as it ash canned them both and started over.

Also, the "trick" valve springs were so lame that when I spun the motor at all it signed off at about 4200 rpm just like it was starving for fuel. That was fun to chase down.

I think the advise to go in and truly find out what you have is sound advise.

Good luck,

Tom

 

Any recent progress Warhorse?