Sorry for the title. Thought I typed "cam" OK guys it's time to just come out with it. Been reading up all over the net about the Lo3, and I never find what im looking for so here goes. I bought a 89 RS with a rebuilt 700r4 (shift kit), & a rebuilt Lo3. They are just past the break in. I need every HP/TQ that I can get out of this set up to make it worth driving (2 years= 200 miles). Their is no point in doing any work that will cost a lot, or why not swap with a 350. Every build I read about that is "budget" is not the direction I want to go. All I need to know is what heads, & full roller cam are the best for the rest of the set up. I want to keep my car forever so the suspension will be re worked from the ground up. I can take care of that part as far as info goes. So I will start naming off parts that I know I want, to give a good idea in order to get the info I need for matched heads, & cam. First off I will not get into the bottom end of this motor. I will not do anything to the stock tbi unit, except for the ultimate tbi mods. I will get a cawl hood to get cold air, & plumb it. I want edelbrock headers that have 3" collectors with no air tube (No sniff test in my state). I will find the sealed high flow cat. Three inch single pipe. Yes a muffler also. No worry. On the other side. I want a edelbrock performance rpm intake. Double roller timing set. Full upgrades on the ignition ect. Did I leave anything out? Any info will help as I am lost on the rest. Thanks in advance for reading this, & for any help. Sorry its so long, but I have yet to find any info on the same setup since no one seems to want to build this motor. I have to. Im not rich, & the motor is like new. Thats my reasoning behind it.

305 limits your choices. I assume you want higher compression? Most small Chev heads I see are 64cc or larger. My 350 with 64cc is at 9.8-10.0/1. Dart Iron Eagle makes a 49 cc head. Not sure what that will do for compression? World iron offers 58cc.

If you keep TBI a cam with a 112-115 LSA is what you want for computer friendly. Duration 216-222 at .05 may be where you want to be.

Trik flow's aluminium cilider heads with 175cc intake ports and 56cc combustion chambers are tempting me.

By searchin tgo you will also find out that 059 vortec's are the best flowing stock heads for 305ci engines.

All other heads that are good for performance will require machine work and/or need porting.

Every mod will require a correct tune, at that point it will be nice to have the stock ECM upgraded with a EBL.

Ya I know the performance end of the 305 is almost unheard of. Thats why I am having trouble finding info for a good set up. Sometimes I wish that the motor was not like new so I could just get a 383, & be done with it. I would have never put the money out to get this motor redone. Dude spent $1800 on it. Less then 3k ago. Crazy. I do want world heads then. Been kicking around that idea. Sounds like the best bang for my buck. When you say that the cam size would be computer friendly, you must mean with a new tuned chip? Is that the max size that I should get? If not then what other bigger size cam might I get with the set up, adding the world 58cc heads? I guess I can call crane or someone to ask too. Would rather find out from a person that has done it before rather then a sales rep. Thanks for the info.

Good info. The only Vortec heads I ever read about need lots of work to get them to fit. Sounds like the best way, if you can afford it. Also I bet T/F heads are a big bite as far as price goes. What about the 58cc World heads? The price is good.

World's s/r stock replacement 58cc. will require some good porting to perform.

Ported 081 's would probably perform better then ported S/R's.

I was just considering heads to achieve your hp goal.

Yes the T/F 's bite me all the time.

Dang it. Did not know it took so much work to get 300hp out of this motor. I tried to sell it, but no takers. What if I use 081's with no porting? How much hp less do you think I will get? Maybe it doesn't cost a lot to port heads?

Porting heads requires time and experience, neither of which tends to come cheaply.

Ya thats what I thought. So what heads are the best to just bolt on? All "budget builds" are in fact done by people that have money or connections. I have none of both, so whatever I get, is just what I get. I would like nothing more then to drop in an ls-1, & t-56, but maybe one day. Until then I hate driving it, like it is. I had a 86 mustang that could out run this car by far. Its that bad that to find a mustang that I could keep up with in an 89 Camaro, I would have to run a 83 Mustang, and still have to have good luck. My dad has my old Mustang. HE put heads, & a cam in it for next to nothing. I want to runn him. My motor is even bigger, yet I have no chance. Thats just sad. Their has to be a way. Its war! lol.

I really wish I could get this stickied, but here you go.

http://www.thirdgen.org/techboard/tb...-synopsis.html (TBI: Condensed Performance Synopsis)

Thanks man. Its seems to me like the best bang for my buck would be to have the stock heads ported, and reworked. Do you think the "LT4 Hot cam 24502586 218/228 - .492/.492 112 LSA" will work good with the stocker heads, and performance rpm intake? If you cant tell im just a parts changer, & this will be my first real performance build. I have worked on heads, but I dont know what parts to get to make it all work effectively. What valve springs should I get ect. should I get a valve angle job also? Maybe I should just get a regular performance intake vs the per. rpm?
I have looked at that thread before too. Its 5 years old. The only intakes it talks about are ones with 2" runners. Then it goes into cams next. That's where I stopped reading, cause of the lack of new info as far as the newer parts go. This is why I keep having to post. I can not find the right info. Also the 7101 perf rpm says its for: "Fits 1955-1986, 262-400 cu.in. Chevrolet V8s". Mine is a 89

Honestly I wouldn't go bigger than an 94 LT1 cam with the stock heads, reworked or not.
Here's a good list for you IMHO.

46mm throttle body (optional) or ultimate TBI mods
Vortec style RPM intake
059 vortec heads mildly worked over
ZZ4 cam with 1.6 intake and 1.5 exhaust or....
XFI268 cam
2800-3000 stall
3.73's with an EATON posi


and TUNING!!!!!!!!!!!!!!! that should get you in the ballpark I believe

man, you chose the low-power economy engine in the f-body, what did you think? it's rather easy outrunning that thing in a 302 HO or similar. i mean, they were top-of-the-line engines, of course they're faster

you don't need that much money to build the tbi up! you just need to gain some overall knowledge about these engines before deciding to buy specific parts and then go on to do all the work yourself. the l03 is a great learner's engine, in my book. you will be able to apply this knowledge on other engines you will modify later as well. you could read some of the books out there, e.g. john lingenfelter's book on the SBC, or one of david vizards about valvetrain & heads to get some basic ideas. that's what i did and it helped a lot imho.

thomas, i think the same about these trickflows, they really sound great! got any cfm# on these? lol you made them bite me again for the next months

robertfrank, i agree with you on the sticky! have you pm'd one of the mods?

you'll never get 300 RWHP from an L03 (unless you have N02) Thats LS1 power. Stock your at what, 140-150 to the wheels?

Heres the flow numbers for the Trickflow Super 23 direct from there website. They list both the 3.766" bore and the 4" bore flow rates:

http://static.trickflow.com/global/i...75%20heads.pdf

Hope this helps

You can get 300rwhp from a 305, its just not cheap or easy. Fast 355 built a 305 that made 423fwhp and 417fwtq. Assuming 25% loss of power through the drivetrain you end up with 317.25rwhp & 312.75rwtq.

Heres the thread Fast355 made for his 305:

http://www.thirdgen.org/techboard/tb...ferrerid=35855 (312 TBI Track times (11.8 @ 119.1))

You beat me to it,I was going to say the same thing,lol

Also if you read the CHP build a few years ago they got 330fwhp out of a L03, granted if they read up on here I believe they could have gotten more out of it.

Why not go with the SDPC vortec heads setup for .525" lift w/ the TBI manifold. Have the heads machined down a bit and run a thin head gasket to bring the compression up. Then run the suggested xe268 cam - there was a car mag that made 372fwhp w/ that setup with a carb, even assume that a bit optimistic you ought to be able to find 300rwhp with something along those lines.

Great idea for bang for the buck. Downside is the cost of TBI manifold that is V specific. Solution might be a standard carb Vortec with an adapter plate. I see Weiand has one at $145.

Check this link out - SDPC sells it as a package, manifold and vortec heads good for .525 lift.

http://www.sdpc2000.com/product/SD80...keHeaders.aspx

K thanks bro.

For that price I bet the light AFR's are better.

AFR's are like $1400 a pair, without the intake, gaskets, etc. A better head, yea, but like $1700 w/ the manifold and gaskets. Depends on your budget.

To drive a 300rwhp 305ci third gen, would be a dream come true for many on this bord.

Lets make a race, who gets them on his car first wins

I kinda agree, there isent much left of the original LO3 at that point.

Heres the link to the CHP 305 build:

http://www.popularhotrodding.com/eng...cks/index.html

That is a very nice build. Again not the same starting point as my motor for two reasons. The first I am unsure about.
1). My car has been rebuilt so I have no idea what is inside it.
2). I think my motor came stock with the roller cam, & flat piston's? Here is what they said about it. "Some of the high-end 305s came with flat-top pistons for more compression ratio, as well as factory hydraulic roller cam setups".

My car is an 89. Do you think that it will make a difference in anyway? I think the compression would not be the same. This part of motors is Chinese to me. That's the hard part. Reason I pull my hair out. I looked up that same page a while ago, as well as many others, & their is always something that to me makes the info worthless. Maybe you can help put my mind around that build if you where to say that it makes no difference that my motor is not the same? Honest this is why I am here. To find this stuff out. Can I use my compression tester to find out the compression that my motor has? If so, how? Thanks for the help. Its hard for me to ask just what someone needs, that knows whats up so thanks for the patience.

I am adding as I am reading. That motor made over 220hp on the dyno in stock form. Mine has 170. Also the test motor had a flat-tappet cam that I am told mine does not have. I also do not want a carb. Seen to many shoot fire, plus I am not wanting to tune a carb once a month.

No this is the article I was talking about. I think they could have done alot better with better exhaust work, plus I don't know how competent their tuning was.

http://www.chevyhiperformance.com/te..._ii/index.html

Your car had the regular dished pistons that came with the motor that they were using and your car stock is a roller motor. Your engine stock should has 9.5:1 compression IIRC so if changing out the heads try to aim for the same or 10.1 for alittle more power. Just be sure your tuning is right and use premium fuel. When your motor was rebuilt they probably use a stock rebuild kit with standard .0039 (?) headgaskets so I wouldn't worry to much.

They were making 220fwhp in stock form because they stripped all the accessories/EGR&AIR off and used an electric waterpump. As you can also see from the picks, that isn't a stock exhaust manifold either, if I'm correct those are full length headers. Add all that stuff back on and use the stock boat anchor exhaust manifold and thats how you make 170fwhp.

I would steer clear of the Edelbrock headers, they suck compared to other options available. I bought a set, looked like a 10 year old put them together, so I got rid of them. Overall, they are just a bad design. If you search the exhaust forums, I think you will find something better suited for your build than the Edelbrock!!!

I'm surprised no one else brought this up already!

EngineQuest Lightning heads, Compcams 26918 springs,XE268H cam. 1.94/1.50 valves,Edlbrock performer RPM air gap intake,650 speed demon carb as per Camaro Performers mag. May 2007 372Hp at crank at 6100 Rpm,peak torque 221 at 5000 Rpms. Look it up see what you find

OK, thanks for the real world advise on the headers. It was not a set in stone deal. I had looked up threads where people ratted on them as well. Then in the same thread someone piped in saying how great they where. The price seemed good also. No one had anything bad to say after the guy posted, so I thought why not. Honest even if I have to wait longer to buy better ones, it would be well worth it not to have worthless parts.

Thanks a lot for all the info Robert. I can tell your a great guy, & you know what your talking about. Thanks to you I found all the info I need for now, & can take a much needed break on the subject. Bet I can even sleep better at night now. lol Its true. I have been banging my head like the picture you have but only with thumbs down. Wish I could have just asked you 3 weeks ago lol. Thanks again bro.

No problem man, that's what this board is for.

the L03 used only slightly dished pistons compared to the pre-87 dished pistons (yielding 8.6:1 in earlier LG4s) and the slightly dished ones yielding a bit more compression at 9.3:1 (like in the 87 LG4, they added ESC in this year to handle knocks). all 305 from 88-up were using this exact bottom end.
9.5:1 was only achieved with the flat-top pistons used in the L69 (HO) and the LU5 (CFI), which despite being early 82-84 stuff were both using ESC already. afaik, about all 305 heads in the 3rdgen have a 58cc (forget the 601 heads for a sec). the standard head gasket is 0.039".

here is a good compression ratio calculator, but there are a couple of more variables to use it:
http://kb-silvolite.com/calc.php?action=comp
deck clearance is usually about 0.025" (piston down in the hole), i can't tell you the cc of the piston dish though.

edit: here's another calculator which appears to be more basic.
http://www.torinocobra.com/Randys_tools.htm

i just read that. what tha hell, 221 peak tq.. i hope that is a typo!?

Thanks for the info. Easy to use chart. I guess the only way to figure out The true numbers is to take the motor apart, & measure everything. I hate to do that. Is this a step that anyone has skipped, by guessing? Also thought the 220tq has to be wrong. They make that much stock dont they.

Well it's got one of the following bore sizes: 3.736", 3.766", or 3.796". I've only seen a hand full of people having pistons that weren't sized by .030" increments. You could check by measuring, but wouldn't need to. You'll get awfully close to knowing your CR with those numbers.

Yes the LO3 makes 255fwtq stock.

as for the one calc from torinocobra posted above:

bore is likely to be different from stock (3.736") so you might just try 3.766 as already said by 89_R
stroke is 3.48" on 305 & 350
cylinders i hope you dont mind if i leave that one out
head gasket stock ones are 0.039" thick
head gasket bore most are 4.1" - 4.2" but it doesn't matter much anyways
cylinder head chamber volume unless your heads were milled they still have about 58cc
piston deck height nominal 0.025 stock but again, you never know..
piston dome/dish volume ANYONE? i know that the flat-tops have 6cc valve reliefs, but dunno the cc of the L03 piston dish.. (prolly about 10cc)

ring height and skirt clearance are imho useless in a CR calculation (as are cylinders)
again, if something has been changed during the rebuild you'll never know its specs until you dig in there and measure everything.

btw, i get 2 minimal different results comparing these two calculators ~~
sorry for the confusion..

i agree, you'll get close, but since you'll be tearing that thing apart anyway, you can make sure to measure the crap out of that engine
peak tq of the Camaro Performance buildup is even rated at the double rpm of the stock L03 peak tq Oo
anyways, it must be a typo.. google couldn't tell me anything about this buildup either

Well I was hoping that I didnt have to take anything apart. Its only got 3,200 miles on it. I didnt do the work so I have no way of knowing what was done or any specs. Just thought I would find the average normal rebuild & guess at it. Didnt know how important it was to get it all right. So if I had to then hey I have to. If not thats way better in my case.

hmm i thought you were planning to do a head swap? if you're actually taking these off you can measure all the mentioned variables, piston dish, deck clearance, chambe cc, bore size, etc!

Yes you are right. Sorry for the misunderstanding. Darn FNG'S. < Thats me

hehe not a problem. think you found the right place to get your questions answered

May be you can help me out? I have a small block crate motor with some mods. I currently have an MSD 6al box, hooker shorty headers,performer carb and intake, and a built up 700R4 with a shift kit. I have some 202 double hump heads im gonna put on it in a week or two. Im wondering what would be a good intake and cam combination. I dont want to push my car past around 5500 RPM. I think it would let go. I need a cam and intake that make power from 1500 to 6500 RPM. What do you think would work well with these heads and numbers.

that's not the way to do it, you should better start your own thread, since this question is not related to this thread and also you're not even using tbi. please post this in the carb or tech section, good luck.