Hi,
This is my first build, just looking for some advice. 406 4 bolt stock crank/ rods, KB flat tops, dart pro 1 alum heads 215cc runner, 2.05 intake, lunati bracket master 2 hydraulic cam .515 lift. This will be going in my 91 camaro with 700r4 trans, 3.73 gear stock height tire.

I'm looking for recommendations on carb size and type. I'm assuming a 750 will be a good size, but vacuum or mechanical secondaries?

I have a weiand team g single plane, but I'm thinking the dart dual plane shp would be a better choice for a primarily street driving.

Will the stock fuel pump from the tbi system be ok for this setup with a regulator, or should I change this the fuel system entirely?

Thanks

 

I'd go with a 750DP myself, and a dual plane intake as you mentioned. Heck, I ran a 650 Speed Demon DP for quite a while and it ran good with it.

These 400's will make a lot of torque down low, and a single plane will contradict that. Not sure about the fuel though....I would assume if you have a return type regulator set at 7 PSI it would work?

 

I think a reg with a return line would be my choice.

 

The stock 400 short rods can not be used for any performance use.They leave the pistons way too far down in the hole.A good bang for your buck is the 5.7 Scat stroker clearanced with ARP bolts.They are less than 300 bucks for the set.It is not that you need stroker clearanced rods,but it is the way they come.Then pistons made for the 400 and the 5.7 rod.In terms of pistons,lose the flat top pistons and use these:



The reason behind that is you still don't have too high of a SCR and can set a quench
of a target of .035 to .040.Better towards the area of .040.And the logic behind that is quench is a anti denotation tool.No boring/honing without the pistons in the machine shop's hands using torque plates.Also,have the rod/pistons available so they can set the deck height.If you ignore these steps,those heads are going to end up being a waste.Set the SCR with those heads no more than 10.5 and DCR at 8.5.

No machine work done on that 400 without sonic checking the bores for wall thickness.These are thin wall/deck blocks that need to be checked.

Once all that is done,plan on paying to have it rebalanced.It will still be a external balance so the flexplate/flywheel and H/B'er is needed to do that.

I don't think I would do 205 intakes because the strength of a 400 is low-end torque and where the 205's really shine is in the upper rpm ranges.A 202intake valve would do fine with a minimum of a 195 cc intake runner.This compliments all the features of a strong runner 400.

 

As long as the intake and cam match it doesn't matter. those bracketmaster cams, though... Id have to think there are better options out there than that?

 

EDIT: Well, seems he already has the heads, cam etc....

So what's his best bet using what he has? Kinda curious myself...

 

I appreciate the constructive criticism, however, I'm citing parts I already have not ones I'm considering buying. As far as my pistons, they are "claimer" pistons for use with 5.565 rods. These set pistons too far down in the bore?
As far as my heads go, they are what I have, not likely to be changed. I'm not opposed to a new cam if you have a suggestion. That's relatively inexpensive. I'm not saying the lunati cam is the best out there, it's what I bought 10 years ago when this project started. I'm finally able to get it finished this year. House and kids take their toll on budgets for toys.

 

I totally understand!

However for anyone to recommend any type of other cam, you need to figure out what your compression ratio really will be - piston cc's, deck clearance, head chamber size, compressed head gasket thickness…all comes into play.

Again, IMO for a mostly street driven car, choose a cam that gives you the most power in the rpm range for everyday driving…like between 1800-5500 rpms. It'll be easier on that 4 bolt main block you have too! These 400's are not built to be high revving engines…they don't need to be since you can get plenty of TQ down low using the cubes you have.

 

Compression calculates out to around 10.5:1