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First Engine Buildup...Looking for 425 to 450 HP

Old Aug 15, 2001 | 11:46 AM
  #1  
Camrs89's Avatar
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
First Engine Buildup...Looking for 425 to 450 HP

Here is what I have and i am looking for about 425-450 horsepower out of the engine.

91 350 bored .030 over
305 Heads "601" casting heads I believe, suppose to be good, any backup on this? Fully ported and polished, milled, 3-angle valve job, largest valves that could be put in it, Edelbrock rpm valve springs
Edelbrock Rpm Intake
Holley 750 D.P.
Holley Red Electric Fuel Pump
No Emmisions on engine

Now, i am needing help trying to reach my goal for the engine with the Horsepower, what kind of cam should I get, I have the Comp. Cam 454 lift but I want something more aggressive, I will be going with a stall converter as well
Need suggestions on pistons as well
Thanks

------------------
Under Restoration:
1989 Camaro RS
350 Carbed engine
Turbo 350 tranny
3.73 gear
and other stuff

Daily Driver (till Camaro is done)
1972 Pontiac LeMans 2Door
350 V-8
Turbo 350 tranny
red with tan top
Old Aug 15, 2001 | 12:55 PM
  #2  
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Those heads are garbage. You will not get 450 HP out of a motor with those no matter what else the motor has. You will be lucky to crack 325 HP.

If there is any one single component of an engine that acts as the upper limit to power output, it is the heads. Think of the engine as a pump, and each of the pieces that air has to flow through as a section of hose. Imagine a chain of 25' pieces of garden hose with a pump somewhere in the middle; and all the pieces of hose are 3/4", except for one that was smaller, say 1/2"; and you made every single other piece larger, say 1", but left the 1/2" piece in there, would the system as a whole flow more? Of course not.

That's what HP is: flow. Technically it's work per time. Work = gasoline molecules. Flow = gas/air molecules per time. No flow, no HP.

If your goal is 450 HP, get some good heads. Edlebrock Perf RPM heads would get you there. Don't use their cam; I'd suggest a Comp XE274H if this is a flat tappet, or a XR270HR if it's a roller. Use their 1302 or 1102 steel roller rockers in either case.

At 450 HP, regular forged pistons such as TRW would be fine. Aim for about 10½:1 CR. Don't do it with thin head gaskets, do it the right way.

Obviously you'll need a good exhaust system... you'll have real trouble getting a decent air cleaner of any sort under your hood if it's stock, don't use a drop base because that will also drop the lid right onto the top of the air horn.

------------------
"So many Mustangs, so little time..."
ICON Motorsports
Old Aug 15, 2001 | 01:47 PM
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Ditto,
you'll need some better heads, like some Trickflow - from Summit $850

------------------
91 B4C 305 TPI - SOON TO BE 383
TREMEC 5-SP, STOCK 1-BOLT REAREAND w/342 GEARS, K&N, AIRFOIL
EDELBROCK HEADERS, DUAL CAT TO HOMEMADE Y-PIPE & 3.5" SINGLE PIPE W/ FLOWMASTER, CRANK PULLEY, MSD, FUEL PRESS REG, COWL HOOD, WELD WHEELS
14.1@ 98MPH
-------------
OTHER RIDE
67 CAMARO - STREET CAR, BIG BLOCK, PUMP GAS
350TH w/ATI 10", 12-BOLT w/373 GEARS
10.47@129 1.55 60FT. ON MOTOR - ET-STREETs w/MUFFLERS
Old Aug 15, 2001 | 01:53 PM
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Don't listen to that crap. You're not the first guy to every make an odd-ball engine run. Some guy won NHRA Stock with a 307 last year so don't tell me this engine won't run. NASCAR has to run a restrictor plate with holes the size of dimes. 305's can run those numbers so why wouldn't more inches run the same numbers. Plus, don't buy that edelcrap. That's all a ripoff. IF you do buy new heads, which I don't know why you would after you put all that money into these heads, buy vortecs they'll give you the power without breaking your wallet. You need to flow the heads and then ask the cam manufacturer which cam you need. If you can't flow the heads I'd get the meanest roller cam you can find with 1.6 rockers and make sure your springs are big enough to handle that combo. You'll probably also have to experiment with carb spacers. You'll have a ton of compression, which means you also have to fool with timing and octane ratings to get the most out of it. Also expect a real narrow power band at high RPM. You'll definately have to run at a 3000 RPM or bigger stall converter.

Having said all that, the other way to go is to make this thing a little torque monster, since the ports in the heads probably aren't the biggest. Go for torque or HP. Your cam decision is going to decide which way you go.
Old Aug 15, 2001 | 02:19 PM
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I'm not saying it cant be done, but its not the easiest way to do it and it wouldnt be a well matched engine. You'll have to really overcam it and spin it 6500+ to make 450hp.
That mean you'll have to build the engine to handle high rpm, instead of spending money on that just get some heads, a good cam and intake = 450hp easy

------------------
91 B4C 305 TPI - SOON TO BE 383
TREMEC 5-SP, STOCK 1-BOLT REAREAND w/342 GEARS, K&N, AIRFOIL
EDELBROCK HEADERS, DUAL CAT TO HOMEMADE Y-PIPE & 3.5" SINGLE PIPE W/ FLOWMASTER, CRANK PULLEY, MSD, FUEL PRESS REG, COWL HOOD, WELD WHEELS
14.1@ 98MPH
-------------
OTHER RIDE
67 CAMARO - STREET CAR, BIG BLOCK, PUMP GAS
350TH w/ATI 10", 12-BOLT w/373 GEARS
10.47@129 1.55 60FT. ON MOTOR - ET-STREETs w/MUFFLERS
Old Aug 15, 2001 | 02:25 PM
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There's only one way to find out. He can run it with these heads and if they really **** him off he can buy new ones and everything switches over. It'd just be a shame to waste all that money, without ever knowing what it would have run.

On a side note, check out Chevy high performance magazine all they ever do is build high HP small blocks. That sould give you a pretty good idea of where to go.
Old Aug 15, 2001 | 02:49 PM
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From: College Station, Tex USA
Car: 89rs
Engine: 400Sb
Transmission: Tremec 3550
some people don't have very high opinion of CHP dynotests. But, that aside, there was no factory head that made more than 400hp in a 350. The best bowties and 292 turbos were only a maginal head for aftermarket. No factory head can compete with current generation aftermarket heads.

Once you put larger valves, springs and screw-in studs, you will have more money in any factory head that you would pay for an aftermarket head.

1.2 hp (approx 420hp) is attainable with a 350. But it is not done by using factory parts. Get the best aftermark heads you can afford and then call comp and get them to recomend a cam.
Old Aug 15, 2001 | 03:09 PM
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
If it was that easy to do then everyone would have a 450 hp SBC with 305 heads. All factory parts have their limits and no mater what you try you won't build a lot of HP with them.

Nascar engines use everything but factory parts and Stock Eliminator cars even though they have plain looking engines can spend over $25,000 to make an engine with stock parts run that quick.

But like I always like to ask, Have you ever driven a street car with 450HP. Considering the only real candidates are late 60's muscle cars with big blocks I'd take a guess and say no.

Most people will be quite happy with 300-350hp considering the majority of the cars on the road are all under 250hp. The more HP you build the more expensive the parts get and the more maintanence there is to keep it running. Also you could build a 500hp engine but if you can't get the power to the ground then it's just an expensive piece of steel under the hood for car shows.

Looking at magazine build-ups is deceiving also. Build a 450hp SBC that makes the 450hp at 6500 rpm. That's not a street engine. Street engines rarely get over 3500 rpm. Build a street engine that peaks out around 5500. That's why GM has TPI. It's not designed to go much above that rpm.

If you really want 400+ hp in a street engine then build a mild big block.

------------------
Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 497.9
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley
Old Aug 15, 2001 | 03:48 PM
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CHP has 7 engine buildups in this months mag. Theres 2 350's in there one doing 330hp and like 410tq and another with 409hp and 425tq.

MAybe worth looking at.
Old Aug 15, 2001 | 04:18 PM
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That one was spoken like a true non-"doer". Any time somebody tells you they're going to get much more than 1 HP per cu. in. out of anything with factory heads, your BS flag ought to raise itself. Any time anybody tells you that a 350 with 305 heads is going to run better, or even anywhere near as good as, a 350 with 350 heads, turn and run the other way. I wish I had just 1% of all the money I've seen wasted by people who thought they were going to do something like that, which basically would require them to repeal the laws of physics. I'd be a rich man.

Vortec heads will not produce that kind of HP. They're good for just about 400 HP on a 350, with everything else just right. They're a replacement truck head, not a performance head. They may happen to have ports that flow unusually well, but they're not a performance head. Like any factory head there's alot of things you can do to them to upgrade them; you can mill the valve guides down to accept a cam with more than .480" lift, you can machine them for screw-in studs and guideplates so you can get rid of the pull-out studs, you can put racing valves in them, you can cut the spring pockets for real valve springs, you can port them... and when you get through doing that, you'll have more money in them than you would have spent on a set of good aftermarket aluminum ones that will work better out of the box than the massaged Vortecs possibly can.

Here's a fundamental lesson in the physics of an engine: power is produced by burning gasoline. Torque (work) is a function of how many gasoline molecules you burn per cylinder fill. Power is the time rate of doing work, i.e., how many gasoline molecules per unit time you burn. The only way to burn gasoline molecules is with air, nitrous aside. Flow = air molecules per unit time. There you have it: if you know the flow capacity of your induction system, heads, and exhaust system; then you know the upper limit on the engine's HP output. Period.

Small heads on a big motor are a mistake. No flow = no HP. No HP = no go fast. Period. No way around it.

Don't fall for that line, typical from inexperienced engine non-builders who haven't been burned enough times by it to know better, it's a very expensive pipe dream.

------------------
"So many Mustangs, so little time..."
ICON Motorsports
Old Aug 15, 2001 | 07:24 PM
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Car: 2006 Silverado 1500
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that is alot of hp to be looking for on a budget. your better off looking for a certain 1/4 mile number to meet. if you on a budget, build the short block as good as you can afford. this leaves room for more improvement later. i'd recomend using your 350 block and having it splayed mains put on it. run your stock crank with some 6 inch rods and a flat top piston. don't go cheap here, go forged or hypereutectic. run a zero gap type ring and a good cam like comp cam's new extreme series. they run great profiles and are great for torque which with an auto is important. for a non roller i'd recomend no. 12-243-3 which is .480 and .498 with 226 and 234 at .050. for a roller i'd go with crane 104224 which is .452 and .465 and 214 and 220 at .050. this cam i'd use 1.6's with though. either one would be nice with roller rockers. for your budget assuming like everyone else your on one i'd say port them as good as you can and have 1.94 and 1.60 valves put in them with edelbrock torquer series springs. run a good exhaust with a performer rpm air gap intake or weiand stealth intake. personally i feel your better off going for a number in quarter than you are hp. this reason being there is alot of stuff to change on the car to make it faster along with adding hp.
Old Aug 16, 2001 | 11:49 AM
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
I am looking to go into the 12's 1/4 with this car. It is an 89 Camaro rs hardtop with a turbo 350 with a b&m shift kit and 3.73 richmond gears

------------------
Under Restoration:
1989 Camaro RS
350 Carbed engine
Turbo 350 tranny
3.73 gear
and other stuff

Daily Driver (till Camaro is done)
1972 Pontiac LeMans 2Door
350 V-8
Turbo 350 tranny
red with tan top
Old Aug 16, 2001 | 01:20 PM
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Hmmmm engine nonn builder & non-doer huh, there's someone with quite an extensive vocabulary. 5676 is a lot of posts for someone building SOOO many engines. Where do you find the time, I simply must know. You also forgot to post your physics degree. You think that 400 HP is the limit for stock parts? That's the funniest damn thing I've heard in a long time. Throwing aftermarket parts at an engine is not a cure all for everything, and I don't know about you but most of us don't have 3 or 4 grand to spend on a set of heads. Anyone who runs these heads right out of the box is taking his life into his own hands. You don't immediately send your heads to the machine shop? Do you even make sure that there's no casting sand in them? Do you make sure that everything was machined right, or are you one of those good enough guys? If you want to live an unexciting and mediocore life then fine, just leave the rest of us out of it.
Old Aug 16, 2001 | 01:46 PM
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Admittedly the 305 heads are not the greatest heads the GM has ever put out. But good God you can make anything flow well with enough work. I know Circle Track racers who run 305 heads on their 450 hp 350's. The engine just end up with a narrow power band. If you put a lot of cam into the engine then it will not idle well put around 3grand it will come around. Then just the heads will hold it back at any point past 5500. You can still make a lot of power in that RPM range.
Do not buy TRW pistons unless you are on a really tight budget. Just step up to some J&E's the piston are about 50 grams lighter apiece. Make sure you have the entire rotating assemble balanced. Build up the short block the best that you can then buy something like World Sportsman II heads.

------------------
84 Z28 383
Stripped w/Cage back halved w/ladder bars and coil overs and 9 inch
700R-4 3.73
I would have a time by now if I could ever get my car back from the shop!!
Old Aug 16, 2001 | 02:24 PM
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
<font face="Verdana, Arial" size="2">I am looking to go into the 12's 1/4 with this car.</font>
Ahh now something more managable.

Estimating with a 3500 pound car and providing you can get the power to the ground without spinning the tires off.

320 Rear wheel HP (rwhp) should net you a 12.9
350 rwhp will get a 12.5
400 rwhp will get a 12.0

If you make the car lighter then less HP is required to go the same speed. Knock off 300 pounds down to 3200 and you'll then need

290 rwhp for 12.9
320 for 12.5
360 for 12.0

To run 12.0 it could be cheaper to build a 360 rwhp 3200 pound car than a 400 rwhp 3500 pound car. Heavy cars are also harder on parts.

Push a 3500 pound door car into the 9's usually need 700+ HP. Push a 2000 pound dragster or altered into the 9's only needs 500HP

Old Aug 16, 2001 | 03:15 PM
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Speaking from actual experience with the 305 heads and to give you an example – In 1986 on a mild 408, mild cam, and pocket ported 58 cc 1.84/1.50 305 heads,,, I pushed around 285 rear wheel. With very similar port work on a set of Dart II heads with 2.05/1.6 valves, the power jumped to around 355 rear wheel– everything else the same. That’s a huge difference with no noticeable drop in idle quality or sound,, not to mention dropping a full second in the quarter mile.

Unfortunately, engine building is about compromises for most of us. So, like ATOMonkey said,, since you’ve got some amount of money in the 305 heads already (can't apply that to another set), run them and see what you’ve got. Like Stephen said,, you might be fine with what it runs even though it’s not going to give you “400 horses” with a streeteable cam and "typical" port work. As Titan mentioned - I also have seen circle track racers getting 450hp out of a big cammed, high compressioned, and "drunk" 406s (running alcohol) using heavily worked 305 heads. And like RB said,, as you can see from this example, there is a lot of power in the heads, and the 305 heads will be the main obstacle in reaching your streetable power goal – which can easily be “fixed” later as funds become available!!!
Old Aug 16, 2001 | 03:39 PM
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From: Hinesville, GA USA
Car: '86 IROC-Z/'94 Z28
Engine: 350 LT1/382 LT1
Transmission: 4L60-E/T-56
Axle/Gears: 3.45/3.42 (soon 4.10)
That's my reason for not using my 305 heads...even though they were ported, I figure I'd wait. They now rest on my garage shelf. Vortec's are great if you're looking for 350 HP. Aluminum 'Vette heads are good for around 400 HP is everything else is OK. TFS heads are really damn good, I'd say you can probably get 500 HP of of them, maybe more. Making HP out of an engine comes down to minimizing restrictions...305's have alot less flow requirement than 350's, and knowing that, the engineers designed those heads to flow less, too keep the velocity high to give a 305 extra torque. Due to the small bore it is supposedly useless to try and make a 305 make high HP. Maybe good for a mild 350 after porting, but not for a high-effort 350 like yours.

The smallest head I would use would be Aluminum 'Vette heads, ported. I'm currently looking for a set. They can be made to flow decently, but still don't quite compete with TFS and AFR heads unless they are CNC'd. I'd say they are good for a healthy TPI 350, but not for a hot minirammed 350 or 383. It all comes down to your budget and goals. Now that I'm thinking of this, I want to look up those TFS aluminum heads in Summit

Good luck either way you go.
Old Aug 16, 2001 | 07:59 PM
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I'm with RB83. ATO, where do you come up with 3 or 4 grand for a good set of heads? AFR, TFS, Dart, Brodix...many good heads out there at a price that is a far cry from those figures. But to get the same overall potential (it's important to not look at peaks) out of 305 heads, all other things being the same...there's your 3 or 4 grand. Do it once and do it right. Buy some TFS heads if you're on a budget and have something that doesn't have to be perfected to reach your power goal. Just my $0.02.

------------------
1990 IROC 350
Mods: Too busy trying to make it run right to mod it.
Airfoil, Dynomax cat-back, MSD coil, 180 t-stat, Bald Eagle tires,
Hypertech fan switch, Accel 23# injectors, Holley AFPR, ported plenum,
Ported Daytona Yellow stock base, Moroso valve covers, other stuff,
Ruger P95DC, hot wife, new oil filter, thick rubber floormats, no cats.
18.0 @ 85MPH since I'm one big-a$$ MF
"It's better to have and not need than to need and not have."
Old Aug 16, 2001 | 08:49 PM
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
As a matter of fact, these heads were going for a circle track car, but I was able to be at the right place at the right time and bought them. The guy, who builds engines for circle track cars, said these heads should be at 400 horsepower, more if I put a mechanical cam and flattop pistons in. He said I will have to change the valve springs because they are for a circle track car, and I have edelbrock springs, which he said will work

------------------
Under Restoration:
1989 Camaro RS
350 Carbed engine
Turbo 350 tranny
3.73 gear
and other stuff

Daily Driver (till Camaro is done)
1972 Pontiac LeMans 2Door
350 V-8
Turbo 350 tranny
red with tan top
Old Aug 16, 2001 | 09:56 PM
  #20  
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Those Corvette aluminum heads were put up against Vortec heads and the new GM Fastburn heads in a recent dyno test (can't find the article right now) any way the Vortech heads beat the crap out of the Corvette aluminums and the Fastburn's beat the crap out of the Vortechs. Vortech heads will help out an engine about as good as any head. If you would like to spend an extra 500 to 600 dollars for 30 horse please send it to me and I will give you 100-150 horse for 300 dollars. Just my two sense. Pun intended.
Old Aug 17, 2001 | 12:42 PM
  #21  
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I'm with RB as well. Sorry ATO, but heads don't cost 3-4 grand. Great heads can be had for under $1000. I just bought brand new AFR 190 heads for $875, with valves, guides, 3/8 ARP studs, retainers, springs. My point is that heads are where it's at, and you can have great heads for less than a grand.

For those all amped up about L-98 heads, they aren't that great. The cast Iron Vortec head will toast them. CHeck out this link;
http://everythingnova.homestead.com/headflow1.html
Third head down on the left column is the L98. Those numbers are weak. Immeadiately below that is the Vortec head, which spanks the L98. Just some FYI for you.
Old Aug 17, 2001 | 01:14 PM
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Car: 89rs
Engine: 400Sb
Transmission: Tremec 3550
it sounds like these specific 305 heads have been significantly reworked and if you got them for next to nothing, that might be a good start. But, as a general rule, that is not a good starting point. Circle track guys have to run a factory head and they often go with the 305 head because of the small chamber volume. But considering all the other things that are less than ideal about that head, I would really not consider it a performance option. The spring seats are extremely small and the castings are very thin. I personally would wait until I could afford the best head for the combination before putting it together, but thats just me.

Could it make 400hp? Well yes in theory. Just remember all it takes is 1 intake cfm of airflow for each 2 hp. That would mean that if they flowed 200, they could make 400hp. Which is definately possible, but thats still a lame way to shoot for 400hp unless its your only option (like circle track racers).

[This message has been edited by jcb999 (edited August 17, 2001).]
Old Aug 17, 2001 | 02:59 PM
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the whole weight to ratio thing...it is just one for reason to go aftermarket, aluminum, they weight so so so much less. Because they are less weight, then that is less hp it takes to get to get the car moven. Plus i also think the aftermarket heads are far far better then GM performance(except for fastburns, kind of like those, but diff intake patteren, but get a manifold match to them, several companies sell them), they are also CHEAPER, that money can also be saved and put into more power adding goodies, it is all a blance of power, money and weight.
Old Aug 17, 2001 | 04:11 PM
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I guess Im out of my league on this but on the 305 heads on a 350 ..... don't people swap 350 heads ... 2.02/1.60 heads onto a 305 to make more power (plus plus plus) ..... We have an engine builder here that builds 305's making 500 horse, granted he has been at it for 30 years and these motors are dead *** reliable and race read .... I guess 4 down draft webbers is not street league.... atleast here it isn't.

Just my experience.

------------------
1989 Trans Am GTA, 5.7L TPI, TH700-R4, T-Tops, dual cats, 9-bolt rear, 3.27, Dynomax muffler, K&N
1992 Camaro RS, 5.0L TBI, T-5, T-Tops, L69 Dual Snorkel, K&N - Sold
Old Aug 17, 2001 | 04:33 PM
  #25  
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Car: 89rs
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i imaging that 305 is actually a .030" over 302. It uses a 4.030 inch bore and a 3.0 inch stroke. A GM 305 starts with a 3.75 bore and a 3.48 stroke. Not quite the same thing. I doubt someone would put an $1800 induction system on a GM 305.
Old Aug 18, 2001 | 04:08 PM
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Car: 88 Firebird WS6
Engine: 350 TPI
Transmission: T56
Axle/Gears: 3.42
<font face="Verdana, Arial" size="2">Originally posted by Drakar:
I guess Im out of my league on this but on the 305 heads on a 350 ..... don't people swap 350 heads ... 2.02/1.60 heads onto a 305 to make more power (plus plus plus</font>

Can't. 2.02/1.60 won't fit in a 305 bore, and if they did, would be so shrouded they would flow less than the smaller valves.


Old Aug 22, 2001 | 11:14 PM
  #27  
HrdRockA4305's Avatar
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From: Peoria, IL
In defense of the original poster, these heads have been very heavily worked (major porting, milled, valves so big they wouldn't fit if they were any bigger, and can handle .7 inches of lift) and yes he did get them for not much at all. I was there when he bought them, they were marked for circle track duty (lots of that around here) but the guy never finished the car or something and was selling most of his parts. I mean ya, a set of Vortechs or Fastburns would probably be better, but for what he paid it'll work for now. At the very least, they're better than the stock heads that were on there before. We're just trying to get the car together and running right now above all else. More power can always be built in later if these don't end up being enough. The end goal is a 12 second car, and these should be enough for that.

------------------
88 Camaro (The mighty LO3 SC!)
305TBI/700R4/2.73/123,XXX miles
14" Open Element and Flowmaster 80 seires

Next up: headers and gears
Old Aug 23, 2001 | 10:32 PM
  #28  
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
Thanks Dave! Actually, the guy said they can outpreform vortechs, did you hear him say that?
Old Aug 24, 2001 | 11:38 PM
  #29  
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From: Peoria, IL
Yep, thats what he said. True or not I dunno, but the guy seems pretty respected aruond here. We'll just have to see what it runs like once its, well, actually running!
I still say keep that cam though.. its almost excessive anyway, something bigger would just be too much I think

------------------
88 Camaro (The mighty LO3 SC!)
305TBI/700R4/2.73/123,XXX miles
14" Open Element and Flowmaster 80 seires

Next up: headers and gears
Old Sep 5, 2001 | 06:22 PM
  #30  
Camrs89's Avatar
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
does anyone think that cam is big (comp cam 454 lift) I am thinking about a 488 lift one. It is a daily driver too
Old Sep 6, 2001 | 03:12 PM
  #31  
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From: chatt,TN,US
Factory heads CAN flow as much as aftermarket. My 462 casting numbers and the supposed *CRAP* edelbrock cam gets me to 8.6 in the 1/8th and thats at 84 MPH which could be faster.

------------------
Bright red 87 GTA with I have stock 3.27 gears,stock converter,B&M shift kit, TRW forged 9.75:1 pistons,comp cams pushrods, edelbrock valvesprings, 462 camel hump heads with 2.02in/1.60ex redrilled for angled plugs, 3 angle valve job, ported and polished, performer RPM intake, mallory fp regulator, edelbrock 750 CFM carb, hei ignition(new) with 10,000 volt coil,No cat, flowmaster 2 chamber mufflers, hedman full length headers, edelbrock cam with 488/501

Best Run 1/8 mile 8.62 at 84MPH, Consistantly run 8.8's
Old Sep 6, 2001 | 08:56 PM
  #32  
Camrs89's Avatar
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
yeah, i am sure these heads are better than the vortecs, but in response to the smaller heads than engine size is junk, my friends GTO has 6x 400 heads on his 455 Pontiac engine and it runs 12.11's. I don't know, I'm a beginner here, but i thought you put smaller heads to raise compression which gives you more power.

------------------
1989 Camaro RS
1991 Truck 350 engine
Bored .030 over
.030 over Flattop pistons
Headmen Headers
3 inch exhaust
305 Circle Track heads
(port and polished like a S.O.B)
Competition Cam 454 lift
Edelbrock valve springs
Edelbrock RPM intake
Holley 750 Carb
Open element air filter
Holley Red Electric Fuel Pump and regulator
MSD Distributor
MSD Plug wires
Bosch Platinum Plugs
No Emissions at all
Turbo 350
B&M shift kit
Richmond 3.73 gears

Future Plans
2500 stall converter
Bigger Cam
125 shot of NOS

Daily Driver (till Camaro is done)
1972 Pontiac LeMans 2Door
350 V-8
Turbo 350 tranny
red with tan top
Old Sep 7, 2001 | 11:27 AM
  #33  
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jrr
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From: Macon, Georgia
I'll second any opinion that favors getting your HP numbers from cubic inches! Sure, even if money is no object, a 450HP 350 is going to have a narrow power band and be a real P.O.S. to drive on the street.

Put your money into some front suspension upgrades to hold up a big block. JEGS has a nice-looking GM 502 big block for sale that would pump out 450HP without breaking a sweat!
Old Sep 7, 2001 | 12:13 PM
  #34  
NTChrist's Avatar
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From: St. Catharines, ON
Uhhh, okay! Yes, you should definitely buy the 502. Screw the bank account, and credit cards. You'll have a big block.
Hell, EVERYBODY should have a big-block! No more of this budget-tuning for me! I'm going to head out and buy 2 right now! One for my lawnmower, too!
Why didn't I think of that? "Just buy a 502." Genius!

------------------
No guts, no glory.
Old Sep 16, 2001 | 05:24 PM
  #35  
Camrs89's Avatar
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From: Pekin, IL
Car: 91 Formula, 79 Trans Am, 72 LeMans
Engine: 305 TPI, 6.6, 350 Pontiac
Transmission: T5, 3 speed, TH350
Can you buy a 502 for me? Also another one for my 72 Pontiac? I'll give you a stock 305 cam strait up.

------------------
1989 Camaro RS
1973 Truck 350 engine
Bored .030 over
.030 Keith Black Racing Pistons
305 Circle Track heads
Ported and Polished, 3-Angle Valve Job, Milled, 1.96 valves,
Edelbrock RPM Valve Springs, 1.6 Rocker Arms
Hedmen Headers
3 inch exhaust w/Flowmaster 80 series
Competition Cam 488 lift
Edelbrock RPM intake
Holley 750 Carb
Open element air filter
Holley Electric Fuel Pump and regulator
MSD Distributor
MSD Plug wires
Bosch Platinum Plugs
No Emissions at all
Turbo 350
B&M shift kit
Richmond 3.73 gears

Daily Driver (till Camaro is done)
1972 Pontiac LeMans 2Door
red with tan top
350 V-8
Turbo 350 tranny

Dual Exhaust w/Glasspacks
K&N Air Filter
Old Sep 16, 2001 | 08:18 PM
  #36  
ede's Avatar
ede
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Joined: Aug 1999
Posts: 14,811
Likes: 1
From: Jackson County
ok i've watched this thread for a long time now and it's gotten pretty far from where it started so i'm locking it, if any of you wish to continue this discussion please feel free to repost. thanks for understanding.

------------------
ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM
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