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Discussion Starter #1
i have 461 heads 202/260s and a 534 -554 lift crane with 1.6 roller rockers. my goal is to get 500hp or 520,530hp something like that.
i have a 85 camaro with everything guted but the doors.i run a standerd tranny and 456 gears. i want to run low 11 seconds. i have a 350 in it now but it lost compretion but i dont know what happend it has like 45 pounds on all cylinders. should i just go with the 327, it is a small jurnel but the 350 is a 2 bolt. i have had nothing but problems with the 350. i decoded it and it is a 307 block 68 to like mid 70s. im thinking it probly came from a engine rebilder once apon a time, it has been through many hands and has 2 sleves. im just afraid of not enuff power. do they make 12.5 pistons or 13to1s for a 327's. if it dont work out i will sell them both and build another 350.
and please dont recomend any 383s if i wanted a longer stroke i would just get a 400cid.

thanks for your help
 

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your info isn't really adding up... a 350 is a 4" bore motor, and a 307 is something like 3.8x. So if you decoded the block to a 307 your first problem lies there, i.e. you never had a 350 to begin with!

No problem though, good 350 blocks are easy to come by.

If you want to make 500 plus horsepower, hate to say it, but bigger cubes are going to make the job a LOT easier.

a 530 horsepower 327 is 1.62 horse per cube, which is pretty radical, and a whole lot of build.

The figure is 1.51 with a 350, still a good stretch.

1.38 with a 383, good chunk lower, not quite so radical of a motor, but still a ground pounding cammer (roller cam, AFR heads, 500+ horse, streetable...)

1.325 wiht a 400CID motor.

As far as not wanting to build a 383 is concerned, I wouldn't either if I had a 400 block and a 400 crank! Who would? But if you can't find a 400 block, or can't find one for the right price and can put the saved money elsewhere, its worth it to build a 383. As you can see from the numbers above (which don't lie!) the biggest jumps in ease of build are from 327-350-383. THe jump to 400 (while actually significant in other ways, as well as cubes...) is not as great.

Sounds like you're on the right track. What does the car weigh now? What 5 speed do you have in it?

Lastly, I don't think the heads you have are going to feed 530 horse.... or really anything over 400. They could, I suppose, but they'll need a lot of porting.

K
 

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Race it, Don't rice it!
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530 horse on those heads isn't impossible, Money wise, It wold cheaper do sell those 461 and get an after market head. Unless of course you can do the work yourself. Is pump gas a choice or rule? Compression will get you there but I don't think you mill the heads enough with a 3.25 stroke. Even angle milling them would drive up the cost further. Their not real good with dome pistons either due to their low plug location. Not trying to be argumentative, just making sure you know what you re getting into.
 

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http://teamrfc.gospelcom.net
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I have a 1969 camaro with a 11.5:1 331 (bored 327) with fully ported dart iron eagle 200cc heads. That car weighs around 3000 lbs and ran a 7.44 in the 1/8th which comes out to around 11.6 in the quarter, I figure that motor has around 500 hp. I also would have to agree that with the heads you have, your goals are a little out of reach. I have another 3000 lb car with a 14.7:1 358 with fully ported brodix 11x heads that has run a best of 6.9 in the 1/8th (around 10.8 in the quarter) but that motor dynoed at 615 hp at 7800 RPM. If you want low 11's a 350 is a must, so are ported aftermarket heads, and some reasonably high compression.

Adam
 

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Discussion Starter #5
i dont know what it weighs but it is gutted but the doors (i have plans for them) if you have any camaro weight or traction experience with these cars let me know.
here is everything i have.
85 camaro z28 305ho
350 currently (made out of a 307 block and 350 crank) Is this possible? all the numbers match up to 307. but crank rods,and pistons are definitly 350.

thinking about the 327 i just got for FREE! (in vary nice shape)
but will still go through it.

borg warner tranny, (i know its going to blow) but hey lets wait and see how long it goes :)

456 and mini spool with a 7.5 rear ( i know its junk to but just till it blows)

461 heads with vary big springs (dont remember specs) full port and polish 202\160s stainless and undercut stems.

longer pushrods (hardend) for guide plates.

536/554 lift 290/298 adv duration 4000 to7500 crane cam.

1.6 roller rockers all aluminum full race stile & poly locks.

long tube headers with headerrap.

shim head gaskets.

high volume high pressure oil pump.

water pump drive kit & a 160 thermostat.

electric fans.

performer rpm intake( soon to go) want super victor.

600 carb but have 750 holley duble pump dual feed (want to make it a 850)

mallory comp-140 fuel pump

hei distributor with curve kit accel module (want a crank trigger)

boxed control arms

short shifter

duble stack k&n filters

open exhaust

new muffler bearings to high speed :) ( just joking) im not that dumb.
 

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Pure American Muscle
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A 307 has a bore of 3.875 and 350 block is 4. If you could fit the 350 crank in the 307 block you would have a 328cid engine or a 333 with a .03 overbore.


bore and crank combo HERE


Chris
 

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What is the thickness of those head gaskets? Are you sure they're giving you proper quench areal? Chances are they're not...

If the block is a 307 there's no way you have a 350 out of it, or even 350 pistons. Its just not possible, you sure its a 307? How are you so sure about the rods and crank? Just wondering...

Further, if you're banking on high horse, do it right the first time. There's a difference between a trans or a rear finally giving up through a normal life and "blowing one up." Ever seen a trans blow up before? It can do any number of aweful things, include sending crap through the bottom of the car and into your nuts. Plus its a danger and a hazard on the track.

A rear is even worse. If your rear lets go on you when you're doing a WOT run, you're going to loose it. Worse, you're not going to have any choice where it goes. I've seen rears rip out entire quarter panels when they fail. Saw a car (old cutlass) with a crap 7.5 rear laying upside down in a ditch once. Street had about 15 ft of posi patch, then it just stopped, followed by said car about 45 ft later. Car's axle failed, kid went to the hospital. His motor fried itself pretty good when the car turned over.

Do it right the first time.

K
 

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Discussion Starter #8
i did some looking some 307s could be bord somthing like
125 over so i guess it could be possible but, from what i found out 307s have vary little nickle or something so they only live like 60,000 and have smoking problems ( cylinders warn out). but i do remember puting 40 over 350 rings on her so, i think she is a little far gone anyway! so what do you think i need for the 500hp 327 (or 350)


thank you for your help it has helped wonders!
 

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chris oswalt said:
i did some looking some 307s could be bord somthing like
125 over so i guess it could be possible but, from what i found out 307s have vary little nickle or something so they only live like 60,000 and have smoking problems ( cylinders warn out). but i do remember puting 40 over 350 rings on her so, i think she is a little far gone anyway! so what do you think i need for the 500hp 327 (or 350)


thank you for your help it has helped wonders!
First of all even though high nickle blocks are desirable there are many a block with lower nickle content running around with well over 60,000miles with out bore wear problems. Boring a 307 .125 over would be something I would not even consiter, good 350 blocks are not hard to come by.
 

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500HP small journal 2 bolt 327? No way...oh it can be done but why give up cubes for a an engine that will grenade?
350 4 bolt, lots of compression and steel everything. I'm partial to aluminum heads for the rapid heat transfer high compression heads need......my .02
If I remember right the 307 was the worst block Chevy ever cast...full smogger......
 

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Scooby dooby doo on down to you favorite machine shop, and discuss with him the possibilities of offset grinding that large journal 350 crank to fit that small journal 327 block...If he knows what he is doing, he can offset grind the crank to give you a 3 9/16 stroke which combined with a 4.040 bore gives you 366 Cubic inches. It is only 16 inches over your 350, but when you are trying to make big power, every little bit helps,If your guy is good, he can offset grind your crank to a 3 5/8 stroke, and that puts you at 372 inches...Pretty cool; you can modify a 327 emblem to say 372, and drive all of the ricers nuts.
Offset grinding is very common on oval track racers as well as bonneville cars, and the small journal 327 and 283 stuff makes it cheap and easy...Throw a set of polished and shotpeened 327 rods in there with full floating pins and arp bolts with good bearings, and it will live forever with a stock oil pump....
 

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i have 461 heads 202/260s and a 534 -554 lift crane with 1.6 roller rockers. my goal is to get 500hp or 520,530hp something like that" out of a 327? 350?

not without sprayin

listen to killer, and elevenpoint, maybe reason
 

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King of my Man-cave.
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With either the 327 or 350, the limiting factor will be your heads. You will definitely have to run 12.5 or so to get the 500 HP figure. I don't think the 461 heads will support the flow needed to reach the 500 HP level. With your cam with 1.6 rockers, you'll have 570-590 lift. Definitely a need for checking valve-to-piston clearance.

A goal of 450-475 HP is more realistic for your set-up, especially with the 327.

tom
 

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Desktop Dyno says that the combination you listed in your second post (with the single plane and 750) will make about 490 hp at 6500. That is with some seriously ported 461s...and 13 to 1 compression (I found flow numbers on the internet). Anything much more than that and it indicates that you're going to need some serious heads. I tried the AFR 180s real fast and they put it up to about 530 hp at like 7500.

Either way, this engine will probably not want to motivate that car under 2500 RPM.

Hope that gives you a little more to go on if you still want to do the 327. Just remember that those numbers are a ballpark.
 

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The lean mean donut machine
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Don't know why you would want to build a 327, unless it's for circle track racing. Having to make power at extremely high RPMs is a recipe for poor reliability and/or expensive parts. Building a big cube engine will be cheaper, allow you to make power at a lower RPM, will live longer, and will be able to swallow a larger cam without as much low end loss. For the money you seem to want to spend on this motor, you could take that cam and throw it in a 400 engine with AFR 195 heads and make well over 500 HP, and do it with lower compression and even be able to drive it on the street. With the huge torque gains you will get out of a big cube engine you could get by with numerically lower gears. At the very least, if you say you already have the 327, throw a 3.75" crank in it and you will get 383 cubes. The block should be able to take this stroke without modifications, and since you have to get new rotating assembly components anyways to handle 500+ HP, it seems like a wise investment.
 
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