What I am looking for is decent gas milage, good low end to midrange torque at an afordable price,500-$2000 for the heads also where can I find an adapter plate for the TBI unit so I can use an edelbrock performer intake manifold (with EGR) need to stay leagle, also doesn't holley make a better TBI unit for these cars here are the modds I am planning, Holley TBI? MSD 6A super HEI Edelbrock TES with 3" cat back, and suspension modds, I am going to use this car as an everyday driver but I just want to make it a little more fun to drive.

 

i would stick to the vortecs... for the 350 of course... jegs has them new for 214 a piece or 250??? i will have to look it up when i get home.!!!

 

actualy I am looking for better flowing heads for the 305

 

For a completely smog legal engine. The World Class Torquer 2 305 heads ($650) are about the best bang for the buck and the AFR 180 heads would be the top end ($1250). Both have the EGR holes in the head and don't require plumbing exhaust gas from the header and don't require the special Vortec intake. The above price is each and its a little over $500 for the pair of vortec heads.

You didn't mention cam but I would hope that you weren't changing the heads and leaving that worthless TBI cam in there. A very popular cam for the 305 TBI engine is a LT1 Z28 cam that cam be swapped right in. 94+ LT1 cams require grinding the dowel off the front of the cam a little so it won't grind against the timing cover. LT1 cam has decent specs and is about as much as you can run with the vortec heads without modifying the heads. If you go with world or AFR you might want to squeeze a little more cam. http://www.compcams.com/catalog/082_083.html

The compcams 266hr-14 or 276hr-14 would be a good choice. You would need to run 3.42 gear minimum and probably a 3.73 with the 276hr-14 to take advantage of the powerband.

If your car is an automatic then a 2000-2800 stall would be a good choice as well. The 95+ S10 4.3L torque converter stalls about 2200 for a cheap converter. Or Midwest converter for a reasonably priced after market stall.

 

yes I was planing on replacing the cam I think I am going to go with an edelbrock cam, and performer intake manifold(egr) and replacing the stock TBI unit with the one that holley sells but to use a intake manifold not designed for TBI I need an adapter plat, to go between the TBI and the intake manifold, I have seen them somewhere before, but can't remember where.

BTW I would go with AFR's, is there a websight I can go to so I can get some specs on them?

 

The AFR's are the most expensive out there basically. I wouldn't. From what I have read and heard from people the Vortec's with a vortec intake manifold base would be your best bet.

Also, I have heard from quite a few people that unless you are gonna run around 300+ hp, you don't need any replacement from the stock TB unit. I'd ask around.

Go with the Vortec's and also the intake, do ultimate mods to the stock TB, replace the cam, adjust the fuel pressure and I think you'd be rolling.

 

I think I am going to go with the AFR's because I do want the car to still be leagal here and we do have smog tests here in houston I think I am going to go with a holley 650CFM 2" bore TBI designed for use on chevy trucks, combine all of what I am going to be soing to it heads/cam/inatke/exhaust/ignition after all of that is done it should be a pretty fun ride but I don't want to go to wild with this car because it is an everyday driver, so I want to get good gas mileage as well.

 

The AFR heads are on http://www.airflowresearch.com

I wouldn't recommend the Edelbrock cam. If you search this board or camaroz28.com or LS1.com or impalass.com, you will find that crane, competition cams and GM hot cams rule the roost.

Unless you are going to be revving that 305 past 6000 rpm a lot then the stock TBI will be fine. You will want to do the ultimate TBI mods to it and replace the injectors but the Holley will be overkill on a 305 and the injectors on some of the Holleys are prone to leaking and premature failure.

I am not going to be the one to say don't do it but there are better ways to get over the 300hp mark. You will get better gas mileage with a 350 with less heads and cam than a ***** to the wall 305 and have the same hp. The less heads and cam will also provide easier chip tuning which will definitely come into play with any head/cam swap.

 

i was looking at some of the Trick Flow heads for a 350 and i was wondering if any one has tried them. One thing i noticed though is that most of their heads have an angled plug design. With an angled plug design work in our cars?

 

i wouldnt go with a edelbrock cam, i dont even think its a roller.
i think you can use an angled plug head in our cars - depending on your exhaust setup.

 

I can't find it right now but some car magizine had an article where they took a 305 tbi camaro into the mid/high 200 hp with cam intake complete exhaust some crappy chip and VORTEC heads on a 305 they just had them milled (not sure if it was an angle mill job or not) untill the combustion chambers were close to the 305 size I think there was a little more work but nothing major that I can remember. any one else remember this?
but yes vortec heads can work well on a 305 ( I think they had to chamfer the top of the block slightly for the bigger valves)
Ryan

 

Id do a 2" tbi. Mine starves for air above 5k rpm, just dies flat on its face about 5.5k-6k. You can use the stock injector (gm) pod on top of the Holley unit.

Check out the GM fastburn heads. They make ~25 peak hp (from iroc22 I believe) over the Vortecs. $800 assembled I believe brand new, you could probably score a set cheaper than that used if you look around.

Put a ZZ4 cam in that baby with a good intake manifold (I like my performer RPM) and a good custom chip and you'll be flyin.

 

what do you need to do make the Performer RPM fit? I know you need the TBI to carb adapter unit but what about the EGR? What about the coolant temp sensor? Also, theres that heater hose connection at the back of the manifold near the distributor, does the performer RPM manifold have a hookup for that? Im just curious here, but that adapter plate doesnt restrict air flow at all does it? Wouldn't' it basically act as a spacer?

 

As far as I know the Rpm intakes don't have egr ports. The adapter is just a spacer. You need one with 2" bores if you intend to use 2" throttle body though. I don't remember if its the TBI caprice or the TPI cars but GM made some cars with different thermostat necks that had a CTS mounted in the neck. I read the that info on here so it may come up in a search. Don't have an answer for you on the heater core line. You will probably have to plumb it from the front. Also, you will have some throttle bracket issues as well to deal with.

 

I didnt see you needed EGR. Check out the GM TBI Vortec Manifold (dont have a pn, but you'll find it on sdpc2000.com). That has egr built into the manifold and you wouldnt need an adaptor.

The carb thing is pretty simple. You'll run the heater hose from the front of the manifold to the heater core, put the cts just about anywhere, edelbrock makes a vortec throttle bracket (just learned that!), drill a new hole in the coil mount and that's all there is to it.

 

it was carcraft i think who did the build up and it was 325 hp not high 200's they miiled it .45 and put a thin 350 head gasket. the cc was milled to 58 i belive the car got 10.0 compression they had a rpm intake and i can't remember all the mods but it look promising...

 

Most of those buildups used a carb and a cam that was not TBI friendly. Also the engine was run on a stand with no accessories to bog it down. I would say high 200's (270 or so) is where the engine would be when it's in the car and TBI compliant.

 

I had world torquer 305's.... got them ported and polished a little bit.. worked real nice

 

Chuck, Please dont take this as a flame, but your engine shouldn't be starved for air at 5500. The reason I'm saying this is so you might take another look and find the real problem. Again, I'm not flaming you or trash talking,but you should be getting more power out of you're combo. When I ran a LT1 cam with edelbrock TBI manifold, headers and stock heads I ran14.93 . With you're heads and intake you should be quicker then that. Presently I'm running a performer rpm and a ZZ4 cam through ported world heads and my stock size tbi is feeding the motor all the way to 6000. I know this for a fact because I have watched the manifold pressure through a few runs using WinALDL.
Peace Brother, I just want you to get what you payed for.

 

Man I know the engine is kinda nuts right now. I shouldnt have even ran it when I did, I only had the thing back together for about a week then I took it to the track. Im still ironing out the bugs and what not, but I just keep hitting obsticles. Yesterday I was trying to fix the fuel pressure and my starter and water pump both went dead on the same day Got those fixed though and I think Im gonna go back out and see if I cant figure out the fuel pressure. Its still running the stock chip, too, just ran outa money. Plug wires are bad... lol the list just goes on and on. I was running 15.8 with just an open element, catback and free mods, but it was only at 84 mph, so I got some mph outa her, just no traction. My damn tps is only reading 87% open under wot...

What manifold pressure should I be checkin for under wot about 5500-6k?

 

Ya, I though you might be having traction probs but I'm thinking you will have another 3-4 mph when you get everything straightened out. MPA (manifold air pressure) is measured in kilopassals (not sure about the spelling) or KPA. Idealy manifold KPA should be the same at any rpm under WOT. If it falls off at high rpm's then you have a bottle neck ahead of the manifold. Could be the injector or in some cases the air cleaner.
Good luck Chuck! hey it rhymes

 

The word is Legal.


The first suggestion was probably the best.

Just an FYI, there is nothing really specific that makes a head a "305" head except that a 305 needs a small combustion chamber to maintain a decent compression ratio (like 58ccs or less) and valves larger than 1.94/1.5 are generally useless at high lift because the bore shrouds the valves.

L31 vortec heads (the heads on the vortec 350) fit the bill valve size wise but will need to be milled.

If I were you I wouldnt waste money on anything new for a 305 that cant be transferred to a 350.

 

simply put....don't waste your money on building up a 305..drive that slow thing around and save up money at the same time for a 350 crate or better

 

Have someone mash the gas on your car without the engine running while you look at the throttle blades in your TBI unit. When I bought my car the TBI was only opening up about 90%. I had to do some adjustments to get it to open all the way. You may have the same problem.