I would have thought you would want a cam with a wider lobe separation, like 112.

I would absolutely get the block Sonic checked, Iquit using the stock blocks after seeing some with cylinders only 0.050 thick in the rear 2 cylinders on a standard bore. Those blocks blew out the cylinders.

 

I had the block sonic checked, all machine work done. The block is also half filled forgot to mention that. I dont understand the logic behind it but that particular camshaft has worked well for me in the past, especially with injection.

 

If it were EFI you'd be absolutely correct on the camshaft LSA.

EFI software has closed loop instructions for overlap conditions (how much exhaust is retained, how much vacuum), and when you exceed those parameters it gets confused.

But with mechanical injection it basically does what you tell it to do by adjusting the butterfly, barrel valve, pill size etc.

 

Narrow lobe centers give broader torque curve but cost peak power, in NA engines.
If it works then don't listen to me. Using a glide? What low gear?

 

Ever since the introduction of aftermarket blocks people shy away from those 400 stockers like its the plague. Lol and I agree 100% aftermarket blocks are FAR superior, if I was buying a block, id buy one over a 400 everytime. But ive got two 400's the one I just built and another. Guess I just like to use stuff up before I move on. Ive ran 3 400's in the past 20 years two 406's and one 421. The 406's went with cars i sold still running perfectly. And the 421 was getting close to failure because of "cap walk" but thats entirely my fault. Ran it almost 7 years and never freshened it up. I've had killer luck with 400 blocks, some people not so fortunate. Maybe im living right 😂😂😂

 

Yes sir, glide with 1.80's

 

Interesting point what you said about the peak HP with tight LSA. The RPM range on that camshaft is 4200-7200 i never turn my motors that hard usually shift around 6500 and depending on what tire/gear i have finish anywhere from 6500-6700....and im in no way arguing against your point just discussing thats what I like, thats how I learn. But me not going all the way to the camshafts effective range, I wonder how bad if any the tight LSA is hurting me? I gues if this was a max effort engine I'd do a little more research on what you're talking about. Im more looking for consistency being a bracket car obviously. And reliability.

 

The tighter LSA is beneficial to the 'Glide, if you were running one of the 3-speeds you might be able to open it up a bit more and in a manual trans app, even looser.

Overall it looks like a good starting point to me as a lot of it will end up depending on what you put it in. I'm not real big on roller rockers and stud girdles but they'll get the job done. Tube size is going to play a big role too, don't be afraid to up it a little on the primary side. Torque convertor somewhere in the 5800 area should work pretty well.

Our 3rd Gen Camaro with somewhat similar specs was a solid 6.15 car at 2650 pounds. This was an aftermarket block, Brodix heads and intake with a 1050 alky carb setup - 421 cubes. Rear gear is 5.38 on a 28x10.5 wide. Current engine is a 434 that pushes the combo to 5.98s. That 421 engine is doing duty right now in the red Nova at the top of this page - the Nova is a little bit heavier and the headers are a bit small - he's running mostly 6.30s with it.

 

6.30's is exactly what im shooting for, the last 421 i had was almost identical to this one with the exception of i had hilborn injection instead of the Wilson intake with toilet that im using this time. And it ran mid 30's

 

If you decide to step it up, there is 80+ hp waiting for you in head porting...the Motown 220 is pretty average out-of-the-box.

I agree that since you aren't taking it up to a 7500 rpm shift point the 112° lobe sep wouldn't really help you. The tight lobe sep is helping to improve the midrange, and that is the rpm range you are utilizing the most.

On methanol you lose some airflow potential because the area is taken up by the amount of alcohol you have to feed it....a 1.6 rocker would be benificial for this, as there are many methanol fuel late model modified engines in circle track using longer duration on the intake side to counter this airflow loss due to fuel volume displacing the air space.

 

I’d probably go with a 225-230cc head in Methanol but a 215-220cc head ion E85 if thats a possible option later on
If your just needed it to stay together I’d splay the caps and send it as is.
Put the extra funds for the 4/7 cam somewhere else tho. If you already bought it, just use it.

 

Yeah like I said the engine is together, I was just making sure I wasn't making some critical mistake. I'll run it a while. When it needs freshened up I may do something as far as head porting and rocker arm ratio may even look into going to shaft rockers.

 

agree with Eric on 1.6 on the intake side
I would have used a bigger cam with a split
bigger heads like 245s
better block to contain the extra hp

 

Not gonna change blocks but do have a lead on some Dart Iron Eagle platinums 230 runners....got 49cc chambers. They are a smoking deal brand new in box. May be worth the swap before I put it in the car. Lot easier to do it now instead of leaning over a fender, coors light and barbecue is catching up with me in the belly department LOL

 

I don't like the valves as they come from Dart, I've seen a few of them fail.

 

the 230 cc darts appear to have a 70% exhaust flow ratio. I would add 8º duration on the exhaust side and as mentioned a bigger camshaft for racing.