FUNIROC

iTrader: (4)

How much HP can you run on the stock 1989 TPI intake (throttle body, plenum, runners, intake) before you have to replace with aftermarket TPI? Or how much with port and polish of stock unit? What all can be done to keep it looking stock.
I am gathering info to have an engine built. I am only looking to get around 300hp out of an engine and no more. As I have a T5 transmission and won’t be replacing it any time soon. I am not going to run it hard just would like the car to have the extra ponies.
Engine can be a 305 or 350 I have a 305 so it will cost just the same any way I go. I am sure I will get hit with the 350 makes more power and is cheaper. If you post it back it up with numbers and link to site. I have looked and the cost is so close not worth the fight about it.
If you replace with a 350 then you pay core, and other parts that will push the cost to only $200 give or take any way you go. I won’t ever need any more power than this build so know need to push higher on the 350.
I am looking at all options but would like to try and keep my 305 just for the heck of it.
So far it looks like around $2300 to my door using my engine as the rebuild. I am not talking about cheep parts with this. I want it to last for a few years.
Thanks

1987ZTPI

Why are you asking for advice, then saying you need us to find the info for you? If you want articles, or proven mods do a search.A l98 will make 300 fw/hp with a set of headers, 3" catback, some ecm tuning, and a set of 1.6 full roler rockers. if you want 300wr/hp about 350-360 fw/hp, then i would be running flat top pistons, some nice 64cc dart, or world products even vortec heads. a nice TPI cam. Comp cams makes a few. 1.6 roller rockers. Headers. First TPI intake system or a base and some nice runners. T/B is good for around 350 hp so no real need for that. 350rw/hp 350sbc will cost about 3500$+ for a good reliable motor. Don't bother with a 305 if thats the kinda poower you wanna make.

305sbc

iTrader: (3)

The TPI will support 300 HP on a 305 engine if done right.
It will take a lot of work on the cylinder heads though.
It will make things a lot easier if you replace the base-plate with a larger unit. Most people wouldn't notice the difference.

FUNIROC

iTrader: (4)

Thanks for the info 305sbc.

Do you have any base-plates that you would recommend?

I am looking at having the heads reworked as well as a lager intake valve, heaver springs hotter cam and at least 1.52 rockers, flat top pistons. Then work on tuning through the ECM as well. I will be installing headers have the 3" catback now.

Also keep it smog legal.

305sbc

iTrader: (3)

Smog legal as in visual or sniffer/dyno or both ?

For TPI parts like the base do some reading in the TPI section stickies.

https://www.thirdgen.org/forums/tpi/...feb-super.html

FUNIROC

iTrader: (4)

As for the smog subject to be both.