hey, hows it goin... i am new to this site, and looking to add some power to my car.. i need some advice.. Right now i have a 305 TBI engine with a full SLP 3" catback exhaust system, 1 5/8" edelbrock headers, 1/2" TBI spacer (turbo city), home made cold/ram air, K&N air filter..... I want to stay with the 305 TBI setup, and want to get around 250-275 HP ... when i do the mods i am going to rebuild the engine and transmission.. my limitations are that i have to pass california emissions and i do not want N2O (no nitrious oxide) other than that i am open to anything.. example: nice set of ported and polished heads, nice cam, dual cat set up, edelbrock intake etc. please give me your suggestions of a good setup sticking with the 305 TBI and wanting to push about 275 HP.. thanks for your help

 

Well it sounds like you are off to a great start with the mods you have. Do you have a 3" cat to go with that set-up. If not I would add a 3" cat to complete your exhaust. Need not worry about dual cats, a single 3" is plenty. I am glad that you said 275 hp and not 375. You goals are realistic and you will be happy with results. As you mod you will see that the 305 TBI is no drag car deamon, but can be set up to make some good street friendly power. For a cam I would look at an LT1 or LT4 cam. These cams are tunable and very street frinedly with a set of rear gears and stall converter (for auto tranny). Since you have emmisions in **** land you may want to look at some ported GM castings or some world products SR torquer 305 heads. More importantly than all of this is chip burning. You will need to have your car data logged and a custom chip will have to be burnt for you to have anything run right. The stock 305 TBI tune is horrible an cannot really support anything more than the stock heads and cam. You will also have to upgrade your intake and fuel suply as well. This includes injectors, high volume fuel pump and potentially a larger TBI unit depends on cam size). If you use the "search" command at the top right of you page you can search in the TBI forum for specifc combos and info on what to do. You will have enough info to read for days. Plenty of newbies out there like you that have the same questions. Good luck and welcome aboard.

 

Your goal is pretty reasonable and attainable. First a 3 inch cat is a big help.. i just upped th oney to get catco 3 inch high flow to match the the eedelbrock headers and 3 inch flowmaster system and wow what i diffeant form the stock cat. second thing would be a cam swap.. crane powerman makes emmission legal camshafts the one i have is crn-104225 from the summit catlog. will work great in a 305 tbi and wouldnt be that hard to tune either.
Specifications:
* Advertised duration: 264 intake/270 exhaust
* Duration at .050 in. cam lift: 208 intake/214 exhaust
* Gross valve lift: .438 in. intake/.452 in. exhaust
* Lobe separation: 112 degrees
* RPM range: 1,500-5,000
* Builds power in the mid and upper rpm performance with a smooth idle
( This part carries CARB E.O. number D-225-22. 50 state legal for listed applications )

the 3rd thing i would say is to pick up a set of 87 and later TPI heads and do a nice port and polish on the and put them on. wont effect emmisions wither and preety cheap to get.

all of the above is assuming you have done stuff like the ultimate tbi and small stuff....

also after you get some of this done you would want to look at things like a better torque convertor. 2000-2400 or so really livens up the car as well. as a trans to handle all of that. also done forget to upgrade the suspension to you wone be able to get any traction with the stock system. also one last thing you might want to look into in a ls1 driveshaft .. good luck...
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