Since I cannot afford a new engine, I have made my mind to "wake up" my 305 this spring. I would like to put on some heads, cam, intake, headers. BTW, I need to keep it emission friendly.

I am thinking about picking up some TPI heads and getting the rebuilt or rebuilding them myself. Should I go with the L98 or the 305 TPI heads???

The cam I am looking at is the PowerMax Emissions Legal Cam. "Serious Performance for modified 305 5spd and 350 w/3.73-up" PN270-114142 in the jegs mag.

The intake would be the Performer Manifold from Edelbrock. PN 350-3704. '87-up heads and TBI, w/ EGR.

I will be ordering MAC headers in the spring.

How does this set up sound to you guys and girls?? I know I'm not gonna be making mad power, just waking it up..

 

Hey great minds think alike. I just did most of that stuff to my '92 RS. I went with the TPI heads, Comp Cams magnum rockers, L98 cam and Hooker supercomp headers.

Definitely an improvement but still not what I would consider fast. I still think my '87 T/A with the LB9 is faster. But I am quite happy with the improvement.

 

From what I understand, the L98 heads will drop your compression. You should stick with the 305 TPI heads. You want casing nimber 081 for centerbolts.

 

good luck trying to get your car to even start with 350 heads

the valves are too big and will hit the cylinder walls

go with the LB9 heads or S/R Torquer Heads

 

I would suggest the World Products SR Torquer 305 heads. They are a direct bolt on replacement and are egr compatible. I think they are the only direct bolt on high performance aftermarket heads for us 305 TBI guys.

The pre-assembled ready to go heads are only $379 each.

 

Which would be better
-tpi heads with rebuild(better than stock), port, polish, valve job, or
-just the S/R Torquer heads bolted on??

Is this swapping/ replacing stuff real difficult?? I have owned only sbc's but NEVER actually done this before. I've worked on a Mitsu. Starion with my buddy and his Civic. (heads and cams)

 

The L98 heads will work with no problem(you will lose compression though). The largest valves that a 305 can use is 2.00in & 1.60ex. The L98 heads came with 1.97in & 1.50ex.

 

Wouldn't losing compression mean losing some power though??

 

Yes. I think the 305 TPI heads are the way to go they can flow as well as the L98's and keep your compression up as well. If you can get a good port job on them I'd say those are your best $ : power ratio.

 

if there's one place in an engine where you should splurge, it's the heads. i don't have the exact words, but john lingenfelter once said a great cam with average heads won't make a lot of power, but a great set of heads with an average cam will.

you can't run 2.02 heads on a 305, so this limits your choices. to keep your compression up, you need to stay with the 58cc combustion chambers, so this rules out even more choices.

if you're going to keep your egr, the factory head choices are the 416 heads for 86 and earlier and the 061 tpi heads for 87 and up. the better choice is the world products s/r torquer 305 heads. they come with screw in studs, stainless valves, heavy duty springs, etc., and they flow better than the factory heads. a set will run you around 800 bucks. you can pick up 416 or 061 heads for a hundred bucks a set, but, by the time you have them redone and upgrade the springs, studs and valves, you'll have 6-700 bucks in them. either way, it'll be well worth your while to spend another 5-600 bucks to have them ported and polished.

now, a lot of guys will squawk at 1,000-1,200 in those heads and point out other aftermarket choices that are cheaper, but i don't know of any other way to keep 58cc chambers and a functional egr and still get those flow numbers.

you can find bargains, though. i set up an ebay search for s/r torquer 305 heads, watched for a few months and got a set of them without valves and springs for 250 (300 after shipping). after valves and springs i'll have 500 bucks in them. another 5-600 for porting and polishing and i'll be at 1100 or so.

if egr isn't an issue, a lot of people go with vortecs. you'll have to buy a special intake for them, but, if you're still running a stock intake, it's a moot point, you'd have to replace it anyway. the best way to go with vortecs is the pro toplines. they're an improved design that isn't prone to cracking, can handle high lift cams and flow a bit better than the stock vortecs. you can pick them up for around 700 a set. they have 64cc chambers, so you'll have to mill them and run an ultra-thin head gasket. warning, this can cause valve geometry problems.

while more expensive than vortecs, the fast burn heads flow much better (again, i believe in putting the best heads possible on the engine). even better, in my opinion, and for less money, are the edelbrock etec 170s. they have a fast burn combustion chamber, but the intake runners are 170 ccs versus 200 ccs (i believe, may even be 210) on the fast burns. those 170 cc runners are perfect for a street engine, perfect balance of torque and hp. etecs will set you back around 1100. like the vortecs, you'll have to get an intake and mill the heads on fast burns and etecs, they're all 64cc chambers.

once again, i believe you put your money in your heads. you can save 400 bucks or so by going with vortecs over etecs, for example, but you're probably talking about 30-40 hp difference, and the heads will have an effect on every other change you make.

if there are better choices, i'd like to hear about them.

 

$5-600 for a port and polish job? Read sittingbull's article about how to DIY on the heads. There is also a very informitive link in his thread to a standard abrasions DIY article, very nice. Anyway, seems to me like you can get the porting and polishing done for like $200 by yourself, figure another $100 for the heads.

From what i read a valve job is highly reccomended, and I'd do; full on rollers w/ 1.6 ratio to help make up for the small cam. the rollers can be had for $300 at the most, if anyone know about how much a valve job runs, i'd be interested in hearing about it.

If you've got money, i'd assume aftermarket is the way to go, if your like me and w/o the dough, i'd look into this route, seems much more cost effective.

-chuck

 

i think diy head porting is beyond the scope of the average enthusiast. it's one thing to do a gasket match or even a pocket port, but a full-on port and polish job? not me buddy.

then, look at the economics. i don't have an air compressor, i'd have to buy an electric tool. the standard abrasives porting kit is over a hundred bucks by itself. i don't have a shop, garage, or even a carport. the neighbors in my apartment complex wouldn't appreciate my sitting out in the parking lot night after night porting away, and the heads just won't fit in the kitchen sink. i'll have mine done by an expert. to me, it's worth the money.

as far as the dough goes, wait 6 months to do your heads, put a hundred bucks a month away and you've got the difference between an average set of heads and a badass set of heads.

once again, don't pennypinch on your heads. you'll regret it later.

a few years ago, i got waaayyyy over my head in a home remodel project i got involved in. first i thought about scaling back my expectations, but instead, i decided to make more money. i work 50-60 hours a week, but, for 4 months, i delivered pizzas a few nights a week and on weekends till i got out of my cash crunch. bottom line? 1) "there's ALWAYS a way" and 2) "speed costs ... how fast you wanna go?"

 

Pepsicola...
Check your email

Ken

 

Good point sean, i forgot that we all dont have the same resources to start out with. I've already got a garage, and a compressor. I can get a die grinder for under 100, and last time i checked the SA kit was only 49.99, and summit has a very similar kit for 29.99. I think you'd still have to pick up some of the cutting bits, but they're not too expencieve.

If you read all of sittingbull's thread he points out many times how it isnt as hard as people make it out to be.

But, sean's right, if you have the money i would definitly go with the proven results and consistancy of aftermarket heads. If you're hard up for cash, and have some of the tools already laying around (like me), go for the diy port. Dont skimp, do it right the first time.

-chuck

 

Thanks guys, I have a lot to think about untill I buy the stuff. I really would like to "do it right the first time" but I don't have a ton of cash, but enough if the right deal comes my way

Cali92RS, thanks for the email, sent one back to ya.

BTW: What are all the different casting numbers??? I've seen a few in the thread so far and I'm a little confused to which are which... Thanks.

 

For 305 heads:

416 casting is the TPI pre-87 using perimeter bolt valve covers. These if used on a 87-later car will need the 4 center bolt holes on your intake manifold ovaled because the 4 center bolts go in at an angle. You can get a new intake manifold that will match up but you will probably have to get one for a carb and use an adapter plate for the throttle body. Probably what I should have done.

081 casting is the 87-later TPI using centerbolt valve covers. These will need nothing. Just bolt 'em on.

187 casting are the swirlport heads of the LO3 and probably what you have now and are trying to get rid of.

Hope that helps.

 

EXCELLENT post Sean.