Damien00677

How practical is it to make 300 hp out of a TBI 305, and how much cash would it take?

iroc22

It's going to take a lot of work. There's no one on this site that has a 300hp 305 TBI.

89RsPower!

umm more cash then it would take 2 build a 300 hp 350 with a carb n replace the 305.

Sitting Bull

If your shortblock is in good shape, you can switch to a carb and hit 300 hp fairly easily. It will require all the stuff in my sig to do it but my car now satisfies my need for speed and gets 19.5 mpg around town too

All these parts will work perfectly well on a 350, too, once you wear out the 305.

iroc22

Have you taken it to the track?

Sitting Bull

No I haven't.

TunedPort 335

Have you dynoed it ?

92ChargedRS

I've been debating the same idea. Build mine or build a 350? The only reason i don't want to build the 305 is i'm worried about the miles on the stock bottom end with new parts. Mostly because of higher compression.
Here are a couple of links to build ups on 305's.

http://www.goingfaster.com/spo/carcraft325hp305.html

http://www.chevyhiperformance.com/projectbuild/48158/

zippy

very much not practical, although it is very possible.

Sitting Bull

Only with Desktop Dyno and asking for the considered opinons of guys like F-Bird'88 and Damon.

Here is the engine mocked up on Dyno2003. It shows it as having 334 hp but I don't believe that. I think 300 hp is much closer to the truth.

Damien00677

desktop dyno seems to be a bit pessimistic with stock engines and quite a bit optimistic with modded engines....anybody know why?
I got a demo and it told me that with my combo (2.8 w/some stuff) I am putting out like 220hp....theres no way

Sitting Bull

It is because it doesn't have enough input variables for things like the intake manifold.

Dyno2003 has more features like this and should be in the ballpark for smallblock Chevs in the 350 range. It was designed around the 300-400 ci displacement model, according to the magazines that have tested it.

Pablo

iTrader: (1)

i dont have dyno numbers just Gtech Competition numbers (like i always have to say, the new, fancier, and more accurate Gtech)
13.7@104.44 mph and a whole slew of 13.8s at about 104 solid, 85 degree weather (best 60 foot is 2.33, crummy tires, driver, and low compression with crappy 3.42 gears)

the engine is a 305 .030 over
214/224 flat tappet cam with 1.6 stamped rockers for .474/.498
edelbrock Torker II single plane
edelbrock 1405 carb with no choke
416 cyl heads fully ported by myself, stock valves though (no undercut)
about 8.8:1 CR
edelbrock headers and full exhaust

Im pretty sure im in the neighborhood of 300 hp

tomorrow im actually reinstalling my heads that have been milled + 3 angle valve job w/ undercut on valves, and some 1.6 roller rockers.

Im looking to go even faster now, if it works out as planned should be about 320 hp

Im gonna try and match this with TBI but 500 cfm is gonna be hard pressed to feed this thing.

For you i would suggest a similar combo with a carb since you just want to go fast. Actually i would suggest a 350 more than anything.

Sitting Bull

That's excellent, Pablo. You running a stick?

Pablo

iTrader: (1)

Of course, I wouldnt have it any other way