*&$%ING FINALLY!

It took three tries and a new cat. Now it's time to dig in.

I've been told the key to the SBC is the heads. Anybody think AFR 180cc street heads would be a waste of money (ie. overkill) on an L05 with a 212/218 .488/.495 lift cam? The alternative would be cleaning up some Iron L98 heads. I just see the price of building Iron L98s rapidly approaching the price of AFRs when you start looking at the machine work required to reliably handle the lift, and in the end I'd still have factory Iron L98 heads. This puppy is a daily driver and I want to keep mileage in the high teens city / mid twenties highway.

http://store.summitracing.com/partde...8&autoview=sku

 

That's good news. Your car didn't sound ruff at the sac GTG, but that has nothing to do with CA smog tests. Was it the last attempt that you decided to change the cat, and was this the reason it passed? Just curious Jason.

 

After the first time I failed I realized that I had changed to a new fuel pump that gave me 13 PSI @ the TBI where before I was getting 11 PSI and had failed to adjust my BPC accordingly. The ~8% change in fuel pressure was enough to throw off the fueling. I adjusted the BPC and put up a stock 1500 CA Pickup timing table and tried again. Results were better and I passed the 25mph, but barely failed on the 15. Threw on a new cat and 3rd time's a charm.

FYI - My AIR injection system is completely non functional and only for looks. I just proved you don't need it to pass. I even passed the engine off as the original L03 (With 1-3/4" primary headers ).

 

Yes AFR heads are overkill on a TBI, in my opinion. You could get Trick Flow 170's or 180's if they're cheaper.

The AIR system helps the cat do its job and maintains a long life. You might have passed the second time without a new cat if it was working.

 

I concur!

 

in other news my 170k mile ls1 passed smog no problem :P

 

Mine passed too. Oh wait, there is no smog here

 

Congrats on Passing. I remember at the gtg you talking about getting your car smogged. It's such a good feeling knowing your car is now saving the earth is'nt it

 

I got tired of smog and bought something old. Problem solved.

AFRs are way overkill for your application. Get some vortecs or L98s. $500-$600 and they'll be fully rebuilt and good to go. 'Course Vortecs mean a new mani..

 

I know they're overkill. Trouble is, my only other option is Iron L98. Don't want to risk the smog check noticing the Vortec intake manifold, not to mention the fact that they don't support standard EGR.

I feel that while AFRs may be overkill, Iron L98 heads may be underkill. I'd rather have more power potential than I'll be able to use than to leave power on the table. Especially in the heads, since my understanding is the best flowing head will give the most power possible without any sacrifices, unlike the cam where stepping up the power DOES come with sacrifices. Plus you get the advantages of aluminum. I know I talked to you about this already urban...I just have trouble like that

But...if a good deal on L98 heads pops up, I'll grab em for sure.

OR HELL MAYBE I'LL JUST STICK WITH THE SWIRL PORTS ^_^

 

L98 aluminum heads wont work with a TBI either. No EGR, old style intake bolt angles, and missing an accessory bolt hole for serpentine stuff.

 

Well there's a few reasons I'd say steer clear of the AFRs unless you've got money to burn... The best prices I've seen on the basic assembled heads from AFR was about $1450 through a local speed shop. You could have a set of stock style 083s rebuilt and pay for the tools to port/polish for the cost of the cores plus $500-$600.

L98s can be worked very nicely to near 240cfm flow on the intake at .500 lift, as can other stock style castings. If you put in the port work yourself you can really come out ahead. This is all the flow you'll need for that camshaft. I know 083 heads can support 450hp when ported and near 400 hp in stock form.

Plus you have to consider diminishing returns. At a point you won't gain very much for your dollar with really nice heads without upgrading the rest of the top end.

Now, if you want to get a bigger cam and better intake/fuel injection setup, then the AFRs will be killer.

In any event good luck with her! Still running my old fuel injectors? haha