Anybody with blown and/or sprayed 305 TPI's? I know of one guy. Just had some ?'s.

 

ask away.

 

ask away.

Ditto.

 

If a car got 160kkms, then do you need to replace anything to supercharger it? Whats a safe amount of psi?

 

Did you buy all forged parts (i.e. crankshaft, rods, pistons)? What about heads, are they factory or aftermarket? Intake, any suggested size (52 and 57 are the only one's aren't they?)? Still have A/C? Do you recommend it? I'll let you answer these first.

 

well, i'm guessing that this is just for a mild street setup. right? i have a stock motor with around 500 miles on (at the time) that i put the supercharger on. nothing is forged. when i step up to my 383, i will go all forged. you leave everything alone if you want, or you replace anything. how much power/what kind of times do you want is the real question.

 

I'm wanting to be 12's or even 11's. Hopefully round 500-600 ponies and same for torque. I want it as a street/strip ride. It's not a going to be a daily driver, an occasional drive to work, mostly weekend crusisng and drag racing. If it have spray or sc reguardless I have to have forged parts am I correct? And what about heads, don't I need aluminum heads if I have the bottle?

 

ttt

 

Anybody at all? Surely someone can answer, even if its not for a 305.

 

Does nobody really know the answers? I didn't think these were too hard of questions or one's that are frequently asked. Should I ask on the TPI board instead?

 

From what I have gathered, for anything over about 350 HP you want to go forged unless you are detonation free and have the motor tuned perfectly. Feel free to correct me or add on guys

 

Finally! A reply. So is what he said true? What about my other ?'s.

 

yes, what he said is pretty much true, if you have anything over 350hp forged is best. you can get by with stock crank and rods till about 400 or 450 so i hear. I am building a 355 to handle 600hp and going all forged. If you have the money, do it. Better safe than sorry. BTW, superchargers are great, power is always there, no bottles to refill. Nitrous is a great alternative. Later

 

Ok, well heck, makin progress here. Ok, so i'll definatly need forged parts and from another suggestion, aluminum heads. Got that.....

BTW, thanx for the replies.

 

I've heard that you don't really want aluminum heads on high power nitrous/forced induction cars because the aluminum is softer than cast iron and have a tendency to wear. I don't know how fast they would wear, or how much of a difference there is, but that's just what I've heard...

 

On blower applications the alum heads actually can act as an after cooler in the sence they will cool down quicker, causing less detonation problems. (quicker per cycle).

Forged of course is the way to go. If you have a motor that runs tho, use it. If you got two years out of a motor before it grenaded, thats better than replacing it now and throwing it in the garage.

A friend of mine runs 11.3 e/t running a 200shot of nitrous, on a stock short-block 2 bolter. (aftermarket heads, intake, etc of course). Almost 200 runs last season and never blew up..

The 305 in my Z28 is a stock short block. I can't wait to blow that up.

-- Joe

 

Um, how would aluminum in an aluminum head wear? All the contact points (valve guides and seats) will not be aluminum and nothing else should touch the heads. Well, I suppose if you never take care of your coolling system you could get galvanic corrosion in the coolant passages.

Aluminum heads absorb heat faster making the engine less detonation sensitive, and therefore easier to tune if you're running a lot of boost.

At the same time, ultimatly, if you are able to get a satisfactory tune with everything else remaining equal you will make more power with iron heads, less of the energy of the air/fuel mixture will be absorbed into the heads and dissapated as heat by the cooling system. Will this be measureable? Donno, I don't know how you would find an identical iron and aluminum head.

Iron will also have the advantage of being more rigid and expanding at the same rate as the block making retaining head gaskets easier.

OTOH, most good heads are available in aluminum, they'll save you 50# off the nose of the car, and they are easier to fix when you blow things up.

 

So iron and aluminum both have their pro's and con's. Whatever set of heads I get is going to have to work with TPI, not all do correct? I plan on getting them ported too and also port the plenum and get different runners and TB as well. I just thought i'd read/heard that if your running juice, it's best to run alum heads. But, I did read about alum expanding and contracting causing the chance of head gaskets to blow faster than normal.