Building a 4.3L for auto class

[Irkie500]

The engine is a 4.3L V6 from an 88 S10 pickup, I dont think its vortec but please tell me if it is. What I need to know is what can I do for either free or below $150 to improve the proformance of the engine. I know it might not be much but hey ill take what I can get. And yes I did see the bolt on thread but im talking about the engine itself, mainly the internals and machine work. Thanks.

[6000nasty]

i dotn think it's vortec. pretty sure its the TBI. as for performance...i dont know ****. sorry

[6000nasty]

round air cleaner will be tbi.

[04silveradomykk]

polish exhaust ports, match exhaust ports to manifolds/headers, polish combustion chambers. Port & match intake ports to intake manifold. (notice I didn't say polish intake ports & runners. wet manifolds need turbulence to help fuel atomization)

hopefully you can scratch up the cash for a rebuild kit with new higher compression pistons and a edelbrock intake manifold & carb. I'm assuming your doing all the machine work in class too, so do some research and find out what the max bore that block will handle without going to thin on the water jackets. Probably .060", and order the pistons to match. That'll bump up a few more cubes. Deffinently a cam, like a Crane 270ah. Or maybe even converter over to roller valvetrain, a 270ahr with roller lifetrs & roller trunion 1.52 roler tip rockers, yeah baby!

Desktop Dyno claims a 4.3L bored .060: over will displace 270.3ci. With a 600cfm carb, dual plane intake. 9.5-1 compression, head work, exhaust work and a hydraulic cam with similar specs to the 270.

Peak HP: 248 @5500rev and Peak TQ: 269 @4000rev

However just changing the valve train over to solid roller

Peak HP: 280 @5500, Peak TQ 292 @4500rev

:cool:

[Irkie500]

hey thanks for the info, about the machine work, were not that advanced so we have to pay machine shop to it for us. Not sure if I would have enough for high comp pistons and an overbore, but Ill see what I can come up with over the next few weeks.

[C4Tom]

I would at least, since it will be apart, install a bigger lift cam. Get a bit more duration and lift.. you'll feel it! See if the instructor can help you learn porting. :D

[wonfast4.3]

We built 4.3's at UTI in our first class. We had the vortech's though. I have a built non-vortech 4.3 in my truck. I would say the porting and polishing is gonna be the easiest way to get free horsepower too.

4.3's at UTIhttp://a963.ac-images.myspacecdn.com/images01/83/l_5453e2e9164cae201f42e5e28cd61a0a.jpg (http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=22716880&albumID=731383&imageID=19020176)

[Irkie500]

thanks guys, i was planning on porting them however if we dont have the tools for it I dont know how much money it will cost me. And about the cam im sure i could land one for a reasonable price.

[White-V-6-S-Ten]

Can you get a set of the vortec heads for that block?
Those heads are much better than the ones you have
But I am not sure if the heads are interchangeable
I know someone else will know!

[rat]

The '92-'95 vortec heads are better than the current heads and are a bolt on. The '96+ heads flow even better, but would reqire a new intake manifold.

[Irkie500]

im thinking about going carb on this engine, but i dont think it will happen this year unless i get the money to pay for a new intake manifold and the carb itself which would be a used edlebrock 650cfm from my neighbor, thank god he is a finatic about car maintence.

[boxcarracer963]

650's alot for a v6 aint it?

[Hammer Head]

..depends on what's done. Avg range is something like 500-600cfm, I believe. A 650 isn't too much assuming it's not bone stock. A good manifold & some headers could handle the 650.. w/ a nice cam, too.

[Irkie500]

ill have my neighbor tell his buddy who gets 4.3L's all the time to keep a look out for the 92-95 heads, if they are in good condition i should be able to buy them for a good price.

[White-V-6-S-Ten]

Go for the 96+ heads they are alot better and you can just got an intake from the same motor and have way better flow!
When building a motor dont skimp, Cause thats what your result will end up being. Not saying you have to spend a boat load of money but if you spend it correctly. And knowing that you can pony up lets say an extra 100 bucks and get a better intake and heads on top of the money you might of spent on the 92-95 heads.

[rat]

Go for the 96+ heads they are alot better and you can just got an intake from the same motor and have way better flow!
When building a motor dont skimp, Cause thats what your result will end up being. Not saying you have to spend a boat load of money but if you spend it correctly. And knowing that you can pony up lets say an extra 100 bucks and get a better intake and heads on top of the money you might of spent on the 92-95 heads.

While i agree that the '96+ heads are better i don't understand the rest of your aurgument.

A new intake manifold would be required, the stock one will not work from either truck. The new controls system would be required.

So, heads would be about 100, and the intake would be about 250.

[Irkie500]

hey quick question what is a safe guess as to what the breaking strength of the internals are, 400 horse?

also what is a safe lift limit for a cam with stock lifters, just need to know so I dont go and buy a cam that wont work.

[Irkie500]

I found a set of used 95' heads for $150 it may be a bit steep but most likely negotiable. The heads were from an s10 also so no problem fitting them on there.

[Irkie500]

well ive been doing some shopping on summit racing and found myself some good deals. A cam with .454 lift Intake/exhaust(desktopdyno 2000 showed a 40hp increase roughly) I also found a whole engine rebuild kit with forged pistons, a new eldlebrock proformer intake manifold, throttlebody spacer, spark plug wire set from MSD and a stage 2 chip from jet all for $1,000 not to bad considering some full exhaust systems are close to that.

[04silveradomykk]

Blew your $150 budget out of the water. I saw it coming

[bespurcell]

Blew your $150 budget out of the water. I saw it coming

Happens every time.:D

[Irkie500]

never said i was going to buy ALL of that stuff, but the one thing i need for sure is that rebuild kit.

[Irkie500]

sorry for double post but one thing i noticed with the rebuild kit is the pistons are alluminium vs the cast iron stock heads, this means I need to get the whole engine balanced and that can cost quite a bit of money.