I'm building up my 350 alot in the spring, and I've started collecting the parts already. I have a few, but not all of these.

- Fresh '79 Z28 shortblock (rebuilt to original specs about 15k ago, stock type dished pistons, etc)

- AFR 195cc (68cc chamber) aluminum heads
- XE274 cam from Comp Cams
- Edelbrock RPM Air Gap intake manifold
- Holley 4150 double pumper (650cfm)
- Vacuum advance HEI w/ hotter coil, weight/spring kit (I'll adjust this as needed when its running)

Right now the 350 is almost completely stock, except for a 14x3 open air cleaner and K&N element, a set of Hedman shorty headers, and a 3" Hooker exhaust with a 3" cutout.

...Now, I know someone who recently built a 400sbc with basically the same top end as what I'm planning (although he used a 750 Demon DP and MSD ignition) and a little bigger cam. He used the same intake and heads, he also has the same rear end gears that I use (3.73)

I've seen his car consistently run VERY low 12s and hit high 11's a couple times. A chassis dyno says he made around 365 rwhp.

So now I'm curious... what would my planned setup, which is pretty similar to whats on his 400, do on a 350? A few guys have said I could hit 12s if I can shift and get tires that stick (I'm running a 4spd, not auto). I'm hoping for mid 13s

What do you guys think?

 

Also, I need to know -

The AFR heads are available in straight and angle plug versions.

Will my headers (Hedman 68470 shorties) work with angle plug heads?

 

Like I said before Adam, I think it is any easy 12s combo. Its pretty much exactly what I started building 2 years ago - the only difference was that I used 1.6 roller rockers and hooker 2210s. I guess you'll have lower compression though...

So far my 3600 lb car has went 114.7mph (118 corrected) so far and there is a bit more in it for sure. I think that 105ish reasonable for your planned setup.

Trevor

 

It could probably take a bigger carb, probably 750. The biggest issue I see is the compression. Depending upon how dished they are, of course. Also, deck height, etc.

You plan on keeping the 5 speed I presume?

 

I'm swapping to a 4-spd. I can't remember the dish of the pistons, but the CR ended up around 9.7:1

Trevor - Your TA weighs 3600lbs?

 

Well then if you go from 76cc to 68cc chamber heads your should be close to 10.5:1 compression but I can't see you having that much compression on a dished piston big chamber head. Was your deck zero-decked?

The car weighs 3600 with me and half a tank of fuel.

 

I should have worded that better.... my CR right now is not 9.7:1... Thats what it calculated out to be with 68cc chambers and a stock head gasket. Right now, with the stock smog heads, its 8.X:1 compression.

Does anyone know if my headers (hedman 68470 shorty) will work with angle plug heads??

 

Should be mid 12s with ease assuming you have suspension mods and traction.

I have mildly ported LT1 heads with an LT1 intake and that same cam and I plan to run very low 12s or high 11s with traction. That's once I get used to driving stick, or if I get a nice big stall on a rebuilt auto. I'm using SLP 1 3/4" headers and have a 10.5:1 compression. My car is pretty light though too. I'm not sure what it is exactly, but by race season next year, it'll be some 325lbs+ under stock.

EDIT: I don't know why I was thinking I have an XE274 cam...I went slightly smaller and took the XE268 grind instead. Either way, I'm still looking for low 12s/high 11s with this cam.

 

Your compression ratio is going to be lower than you think with dished pistons and 68cc heads on a 350.
Is your block decked? A factory piston does not come all the way to the top @ TDC. Some rebuild pistons actually sit lower than the factory piston @TDC.

you are not stuck with a 68cc head from AFR.

Head milling and chamber cc check is a extra cost option that you can order for your heads if you buy them factory direct or from a supplier that does its own machineing. ( machine shop) Milling the head will reduce the valve to piston clearance and effect the push rod lenght.

 

just my opinion,but I really think your looking at high 12s once you get your combo sorted out and in tune.
ever thought about a 125 hit of juice?I had great success with it in a cast piston 355 a few years ago,I just followed the tuning instructions to the T,and never hurt it a bit.

One last thing,I say stay with the 650,it's plenty of carb.Proform main bodies are cash very well spent,though.

 

Blow up


na, high 12's perhaps Low 13's?