4.3 performance non-existant?

[406ben]

A while back I posted the 4.3 Chevette PT project I've got going. I've searched and searched and can't seem to find any serious performance parts for this motor. It seems most cam manufacturers list only small "performer" style cams if at all, and there only seems to be "performer" style intakes available too. Don't they use these motors for Nascar type racing? I would think there would be boatloads of parts out there for them. GM performance has a single plane Victor Jr. type intake available, but it only works with their "Pontiac" aluminum Nascar heads, which are actually very tempting, but spendy.

Any leads for shops or parts suppliers out there that deal with serious hp (400+) 4.3's? Thanks in advance!

[myclone]

There is actually quite a bit of performance parts available for this motor but once you get past the typical smog legal/bolt on stuff it gets expensive quick due to a small market for all out parts.

Comp cams has several roller cams in stock or will custom grind you one as big as you want (I have a custom ground .745" lift cam from them for a 4.3).

The stock crank is good to 400hp easily but the stock oiling system does NOT like high RPM so time needs to be spent on it. Aftermarket cranks are available up to 305cid but the cheapest Ive seen them is $2500. Stock rods are horrible so replace those with Eagles or Olivers. Olivers are spendy but worth it while Eagles are a little heavy they are cheaper and have pegged the dyno at 700+ftlbs without problem so far.

Intakes arent something you find a lot of other than the dual plane set ups like youve found out but if youre going forced induction with a 400hp goal IMO one of the readily available dual planes will be more than adequate. If you really are against the dual plane then your options are limited to a Syclone/Typhoon intake or one of the single plane intakes that show up on ebay once or twice a year that were used on the ASA/BGN cars back when they ran V6s. You could always go custom sheet metal but youre looking at ~$2k for one of those from Hogan or similar companies.

Ill dig up a list of links for companies that sell 4.3 performance parts and post back later but be aware that 99% of those parts are geared toward the Syclone/Typhoon turbo set up and are usually priced accordingly.

[WELTERRACER]

4.3 parts are the same as 350 parts.. so it is usually cheaper to buy pistons and rings for a 350 and install them into the 4.3L... You will have to do some research thought... THey did a build up a while back in I believe it was HOTROD or CARCRAFT that did it..made 300hp.. They also later added a vortec supercharger to make 450hp..

You can build up the stock heads installing larger valves and better springs but you have to do alot of port work to make them flow... and they still dont flow that well..

[JL8Jeff]

I think GMPP has a crossram intake for the 4.3 that mounts a single 4 bbl carb.

[Lowend]

Is this a odd-fire or even fire motor?

[myclone]

About everything you would want for a performance 4.3 out west can be bought here.
http://www.raceprovenmotors.com/

Same deal here only on the east coast.
www.turbotime.us

Midwestern location for 4.3 performance parts/help.
http://www.tobefast.com/default_automotive.aspx

All the usual small block 350 parts like pistons, rings, valve train, main bearings, main caps, oil pump, and accessories will carry over to the even fire 4.3. Odd fire 4.3s can use 350 rods and rod bearings as well as the above mentioned parts.

Heres a decent deal on heads/intake.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33617&item=7968533615&rd=1&ssPageName=WDVW

FWIW, Ive seen the stock two bolt main caps w/ARP studs start to walk which hurts main bearings in turbo apps approaching 600hp so investing in either Bow Tie splayed caps or Pro-Gram engineering splayed main caps would be a wise investment IMO with a stock block. Bow tie blocks could prolly get by with two bolts but I personally wouldnt risk it considering the cost of a bowtie block if its damaged when the engine scatters.

HTH..

[myclone]

You can build up the stock heads installing larger valves and better springs but you have to do alot of port work to make them flow... and they still dont flow that well..

Very true on the old non vortec style heads. In the syclone/typhoon community its been proven that stock 95-up vortecs will out flow fairly significantly ported stock heads from the 87-92 vintage.

IMO dont bother with the old style heads unless you enjoy spending countless hours with a die grinder to get very little flow. The combustion chambers on the old style heads are horrible not to mention detonation prone compared to the vortecs. Vortecs can be picked up for 50-100 bucks in ready to run condition off of egay and with some minor bowl blending can be made to flow a decent amount. Plus you get a better combustion chamber with more quench with the vortecs.

Lemme put it this way...Unported vortecs have been 10.29 in the quarter on a bone stock appearing syclone (3500lbs+AWD) with 27lbs of boost. Stock old style 4.3 heads like the mag wasted its time on will only go that fast if they are in the bed of the previously mentioned syclone.

[406ben]

Excellent! Mucho apreciation for the tips! O.k, I can build a nasty small block, but am clueless about 4.3s. How do I tell which way it fires? It came from a 91 4x4 s10 Blazer with a non hei type distributor and a throttle body on a dual plane type intake FI system.
Thanks again for the tips!!:yeah:

[4OfaKind]

Click http://www.bigalstoybox.com/small.html and scroll to the bottom. I was surprised. I think you will be too.:icon996:

https://static1.pt-content.com/images/noimg.gif

Oh I did not see that you were turbocharging. :hand:

[myclone]

Excellent! Mucho apreciation for the tips! O.k, I can build a nasty small block, but am clueless about 4.3s. How do I tell which way it fires? It came from a 91 4x4 s10 Blazer with a non hei type distributor and a throttle body on a dual plane type intake FI system.
Thanks again for the tips!!:yeah:

Any production 4.3 will be even fire. Even fire means each rod has its own journal on the crank so that ignition happens every 90 degrees. Hence the "even fire" name.

After market or bowtie cranks that are odd fire have whats called a common pin crank which means pairs of rods share a journal just like the SBC. With this set up you get a firing sequence of 90 degrees and 120 degrees (I think...my memory is getting rusty). This is where the "odd fire" name comes from.

Basically any production 4.3 engine you get that came with FI will be even fire. Some of the older 229 V6s that look just like the 4.3 on the outside were odd fire but they were all carb'd anyways so its easy to tell one from another unless the engine is in pieces. If the engine is in pieces then anything with a two piece rear main seal will need to have the bore measured if you cant look at the bottom end for the common pin crank unless its the odd ball one year only carb'd 85 astro van 4.3 with the two piece rear main seal.

No mechanical fuel pump rod actuating hole in block=Even fire (cept for the 85 astro van)
Fuel injection=Even fire (cept for the 85 astro van)
One piece rear main=Even fire (cept for the 85 astro van)
Center bolt valve covers=Even fire

Parameter mounting bolts on valve covers (like 1st gen SBC)=Odd fire
Carb'd=Odd fire (cept for the 85 astro van)

FWIW, try to avoid 94 and newer balance shaft motors as the blocks arent quite as rigid for all out HP as well as smaller after market cam selection. 94-95ish heads are better than the early pieces and are a direct bolt on (commonly called L35 heads). Vortecs are best but require redrilling the intake mouning holes if you use an early style intake. If you go vortecs then the newer the heads the better generally speaking. Try to get a 4.3 out of a full size truck with the flush mounted circular pads on the front (located under the accessory brackets) as they are rumored to have the beefiest block and better cranks.

Instead of me typing all this out here is a link to some good info on 4.3s.
http://www.syty.net/forums/showthread.php?t=20725

HTH

[406ben]

I clicked on the link to race proven motors and I about crapped my shorts. WOW!! It's spendy, $500, but they plumb any intake with fuel injectors, billet fuel rails, and they use Ford throttle bodies for a home built sweet looking set up. Stroker cranks for 300+ inches! I wrote the technical dept and they said turbo induced 500 ponies on 91 octane with Vortec heads is achievable, and they stock everything I'll need. Dang, I hit a gold mine! Thanks for all the info guys!!!
With all this new stuff, I've considered mini tubbing and running fatter 245-35-18's on the rear. Rickham rackem, more money....

[inSANe DIEGO]

Ben,
Keep me/us posted on the 4.3 if you do it. I'm a long time fan of the turbo 4.3 and I am planning to do one- digging for the info (and $$$$ :doh: )to get it done.

[KacyZ28]

ill get some info from my friend who has a 4.3 that was scheduled to be about 350 hp and he lost intrest

[gmachinz]

If any of you are interested, I can have a cam custom ground for you on those 4.3's-drop me a pm on what you'd like and I'll see what I can do. -Jabin