Don't they put a chamfer on the top of cylinder by the valves just to aid air flow into the cylinder for the oversize valves? I remember doing that on my 440 mops, on the 2.14in intake valve and 1.88 exhaust.

 

Thought I would drag my old thread out of the archives and ask for a little help! I have decided to build an individual runner intake manifold. That is not a problem yet...... What I need advice on is what size of injector lines do I need to get. Probably go with large than stock. Got my tubing benders ready to go! Also thinking of no intercooler at all. No towing plans for my 98 at all.....

 

John on a street truck run the Intercooler.. it is nip and tuck if it is worth it on my truck, but on your truck definately run the intercooler,, in fact be a good idea to get a bigger one

 

Thanks Kevin..... Was looking at intercoolers and I guess I am not going totally pro comp! LOL Guess I have to get to E town or Calgary once or twice a year for spin on some rollers.

 

I am sure I could look through this thread and find out, but what size pump are you running? If its a 12mm, I won't require anything bigger than .084". I think .076" is stock. You can get .093" and up to .120" lines, but unless you are running a 13mm and dual feed injectors, I don't see the need.

 

I have a 913 pump, which I think is still a 12mm pump. Not sure though. I can see a stupid pump in my future. What are the drawbacks of too big of injector lines? The .093 might be what I want, but not need! lol

 

I'd say delayed timing and a lazy end of injection event, since there is much more volume of the line that compresses, and the line itself will expand more. IIRC, the lines have the same OD. 913 is a 12mm pump.

When you get lines, get mild steel. Stainless likes to crack.

 

So does this mean I run more timing advance??? Solving 1 problem and creating another!

 

You could do that, but it will likely have a sloppy finish, which means more smoke and heat. I'd sure like to know what the timing differences would be between stock and bigger lines.

 

So what size line do you suggest? I have DDP 4 injectors, 191 dv, the 913 pump and 4k gsk. But will be going with more fuel possibly if I am not having enough fun with the power level that this engine is going to give me. I am getting new lines no matter what, now that I am chopping off my stock intake.

 

For what you got, stock size would be just fine. .093" if you want bigger is what I would guess at.

 

Swamp, you might get more power, if put in a 5gsk. Tate has provided some good info on pumps. Was your 913 pump flow benched? Realistically, you should be around 700-800rwhp with that pump on fuel, if everything works. I would just spray nos or water/methanol for the events. On spray you possibly be around the 1000rwhp area.

Without lots of head porting, and reving up your engine to 5000 rpm's, there is no real advantage to using the zz intake.

Going to the big pumper, you pretty much have to build the engine around that pump, if your going to make power.

 

Swamp, just thought of an idea for ya to think about. Its cheaper than the zz intake. How about throw a 6.7L crank into your engine? I saw them on comp forum for $300 dollars. You get 410in motor from going with that crank.

 

This is the beginnings of my individual runner intake manifold.......

 

Mike, now that you say I need to spin this to 5k I guess I have no choice but to get a stoopid pump! LOL Wont be for a year or 2..... these engine builds seem to get a bit pricy.