I am looking for help building a 460 over the course of the nest year. I am looking to produce around 450 to 500 horse. is this easily accomplished? Trying to geat as much power for as little cash as possible. Suggested parts? Any advice or suggestions would be of great help. It is going to be backed by a c6 to start and hopefully an AOD down the road. possibly adding a small? 100 to 150 shot of nitrous later. It is going in a 81 f100 stepside that i want to build to crush all the mustangs and camaros. Sorry apout the long post and thanks for the help. Jack

 

Heads will be your limiting factor. Any of the early C8. C9 or DO ('68-71) or late D3 ('72-78) heads can be ported to handle 500 or more hp.

Good luck dusting LS1 Camaros with a 5000lb truck. Those are low 13 second cars out-of-the-box. For 5000lbs to turn low-13s, you'll need about 575hp at the flywheel with a 25% driveline loss. 575hp from an iron-headed 460 will require a cam that may not be much fun on the street and a high stall speed torque converter. And another $500 of mods puts the LS1 into the 12s. You'll need the spray. Lots of it.

 

Hmmm.... you sound just like me when I first strated my rebuild project. Only differance is that I wanted to lift the front tires off the ground just enought to see day light. It is very possible to produse a 450 HP motor using D3VE-A2A heads (92cc) the trick comes fromt he lower end being built to withstand the high rpm's. I have my block still at the machine shop being blue printed. Next Monday I am going over to balance the rotating assembly myself. Helps when you talk with the machinist so much you turn into a part timer. The thing you have to keep in mind is price. I am shelling out roughly $1000.00 in block work and $350 into the heads. This is not including the parts. I slowly started to stock pile my parts to allow me to do the block then the heads. I am using a Comp Cams Xtreme 4x4 cam with .544 I and .564 E, 226/234 duration at .050, and a LDA of 111 which will give me 513 TQ @ 4000 and 456 HP @ 5000. Once I switch to 72cc heads I will be running around 536 TQ @ 4000 and 502 HP @ 5500. Close #'s but a noticable increase. But my max rpm is still around 6200 before the engine output starts to dive. Now with that said you also have to look at your driveline. The rear end gears are going to have to be swapped out for a higher ratio plus you might need to purchase a limited slip or detroit locker to apply all the TQ to the road otherwise you are going to be known as the burnout king. Open carriers love to break loose like it is cool. Just remember to ask all the questions you can and set yourself a realistic budget. Don't shoot for the stars if you only have a 100 foot ceiling budget. Hope this helps out a little more then it confuses you.

 

hey man,
if you want around 450 i would go with a set of police interceptor heads, cam around 220@.050(dual pattern, favoring exhaust side), 1.73 roller rockers, good four barrel intake(such as the performer rpm), probably an 850 carb and at least 9:1 compression. it was either hot rod or car craft that built a 460 that made 434 hp 497 lb/ft with 8.8:1 comprssion, dove heads and above carb and intake. i dont see why you couldnt make close to 450 using a lil more compression, slighly bigger cam and the pi heads. and as far as getting a truck to wax f-bodies, i see no reason other than traction that you shouldnt be able to with 450 hp. the new lightnings are runnin low 13s with 380....there may be a bigger weight difference than i think....so i may be a lil off....but good luck

mike

 

If you want a drag machine, use a lightweight car or tubed chasis truck, not a street truck.

A 460 in a 5000lb truck that produces 450hp at the flywheel will, with a 25% driveline loss, put 338hp to the rear wheels. Based on that, it will show a 1/4 mile elapsed time of 14.3 seconds. And that's assuming optimum gearing.

A LSI in a 3400lb car that produces 335hp at the flywheel has a 15% driveline loss and produces 285hp at the rear wheels. That's 13.3 seconds 1/4 mile elapsed time with 3.23 road gears.

The effects of spray (nitrous) are proportionate to the weights. A 100hp shot to the 460 would provide an ET of 13.4. 100hp shot to the smallblock an ET of 12.2.

It's a losing battle as the truck weight makes hp gains related to decreased elapsed times much more difficult than in a lighter weight vehicle. And the first thing most LS1 engined car owners do is put on a lid, MAF and chip, which easily puts them into the 12s without spray. 12.9 in a 5000lb truck takes 613hp at the crank.

I like trucks, but if you want to be king of the stoplight crowd, a car is your best bet.

 

georgedavila, can you run a car that weighs 2600 lbs and 400H.P. will do? what does you computer show? I'd like to see what my monza does with that horespower. It also had 295-50-15 tires and 2.92 gear ratio, thanks.

I hope i'm in the 400's of horsepower with my 460. I have 750 carb, performer intake, enlarged valves, sloted rockers,a Luntai cam (Bracket Master II), and 10.2 to 1 compression, with an all out MSD ignition (blastor 2 coil, 6al ign box, and Probillit Dizzy) and lasst but not least, Hooker Super Competition Headers. No one will even give me an estimate! Could you please? thanks

 

There are lots of automotive math calculators on the net. You sometimes have to use one factor, like ET in this calculator, to solve for hp:

http://www.smokemup.com/auto_math/hp_et.php

The big factor in your hp is the heads. You said bigger valves, were they ported? And you could use a 800-850cfm carb. To get an accurate hp/tq estimate, find somebody with DeskTop Dyno to build a file for you. I believe Eric185 has access to that.

 

Not to jump in on dashing your hopes for a fast truck, but the newer cars have little wind resistance compared to our trucks.If you have ever been around the 100 mph neighborhood in one you know. At 140 mph in my truck feels like a hurricane is fighting you. The ls1 cars push 150 mph with less hp. I started with a mild 429 in my truck. I then built a hyd roller cam 460. My total gain in hp was probably around 100 hp. My total gain in performance is minimal. Just be realistic in your goals as stated or you will be sorely disappointed after spending lots of money.

 

Wow thanks for all the input guys. There are not a lot of ls1 equipped camaros around here. A few LT1 and mostly TPI and carborated modles. I will have to look at the door sticker again and see what it weighs, but 5000 lbs seems high for a little short bow 2 wheel drive stepside. Though I dont dought it. Where should i look for for the heads, I am goig to dig through the junk yards for a good set then down the road maybe go with an aluminum set. But what would those police interceptor heads be on? Hey Air Harley what is being done to the block that is so expensive?

 

I am having the mains line bored, having a true decking done (install pistons at 4 corners and mic the distance to the top then cut the decks. gives a consistant CR for each cylinder vise a round about), magniflux, blue print, balancing the rotating assembly below .010 inches per second, bored .030 over, and a few other items like installing screens and knocking the casting flash off the inside. I went to a guy who has been workign on top fuel dragsters and such for the last 27 years. Experiance sometimes cost a little, but you want the engine to last no matter what you throw at it right?

 

Most of the PI and CJ/SCJ heads were collected a long time ago. Finding a virgin set in a boneyard would be akin to winning a lottery. I just sold my last set of PI heads (bare) for $450 and could have sold several more if I had them.

By the time you do a set of PI or CJ heads right, depending on how much the initial cost was, you'll be within a few hundred dollars of new, complete aluminum heads. Figure $200 for SS valves, $200 on the seat grind and surfacing, new guides, the cost of new springs to match your cam, retainers, keepers, studs and guideplates. Throw some porting in and it does add up.

Iron production head requirements for puller and mudder classes are what have driven the prices.

 

5,000 does sound high. More like the GNAWB weight which is not the weight of the truck but the weight plus it's carry capacity of passengers and carrying load in the bed.I'd say your truck weighs more like 4,500 or 4,000 lbs.
My father-in-law's 434 with 290 cam, 2800 stall and basic mod's in his '68 F100 eat's the GM family all day long. You can do it, just need careful planning & research of which parts to buy.No one is saying you can't do it.
Don't forget the efi heads. They are cheap also. When properly ported and 2.19/1.76 valves installed they will outflow any cast iron Ford head on the exhaust because of the raised ports and not be far in cfm on the intake side even with the smaller ports.The only problem is you can only use the CJ intake with them other than the restrictive stock intake.
I would probably go with a 400 (w/.040) over the 460 if stomping the GM group is your goal. The torque from a monster 460 would not let you out the hole without spinning and going no where especially with the light tailend. The 400 will rev faster than a 460 and the torque comes more in at midrange where you can use it. It's about 80 lbs less in weight depending on how and what you use. I don't want to discuss this too much because this is the 460 forum. You get the idea though.

 

I don't know what my et is but, my F-250 4x4 will run 95 in the quarter and it weighs 7000#. I have been told this is about 400-425 hp.

I can post the exact motor specs if needed.

BTW you won't find an AOD for a 460 because they were never made. I have heard that Art Carr makes one but, you better be prepared with you wallet.

 

None of the stock or aftermarket carburated intake manifolds will fit EFI heads without extensive milling.

 

Only the Cobra Jet intakes fit....