So, adding together the volume of the upper and lower plenums we get 9.5c which = 2.25L. If you add in the neck volume we get 11c which = 2.6L I think this is pretty darn good!!!- approaching 2.85L which is "ideal" assuming 1.5x displacement is a good plenum size.
I also measured the "neck" outlet in my plenum. It's 70mm in diameter. The "neck" inlet at the throttle body flange is actually 60mm.
Hmm. That's pretty close to what I was going for. I think I will try to use the stock TB and see how it does. I might try to port the TB outlet some to match. That will save the PITA of making new coldside IC tubing and getting a pipe and flange welded on and making the new TB work.
I want to put this **** on my car right naow. I just got my COPs working and went for a drive yesterday. Time to take it off the road again...
i cant wait to see what the car will do with this new intake manifold!!!!1
Don't port your TB, you'll have huge intake leaks and won't keep the idle below 3k
??? oh I guess that will happen if like a douche you hollow out the whole thing and your butterfly can't seal the pipe.
Originally Posted by Braineack
what is the length of the runners?
If you wanna port the TB, use maxbore.com
maxbore looks pretty cool. I wasn't thinking of a full TB port. Just radius the outlet of the TB to transition to the 60MM inlet. Will also cut the gasket to match. (waiting for it...)
Originally Posted by 18psi
Whats the point of bottlenecking your newly ported mani with a stock tb?
stock tb will still flow... 5000 I mean 500hp has been attained on super stock miata IM and TB. Not mad 70mm flow but it will still work and if lameness occurs on the dyno readout I can whip out my sawbaby and go to town.
With my current turbo, if I had eliminator's luck and tune I could hit 570!!!!!!! He had the old garrett T3 50 trim which is only rated at 46 lbs/minute and mine is about the same so maybe I will hit 570hp too. but yah right seriously now, on a dyno dynamics I hope to hit 100hp below that. my secret plan is to go for 32lbs of boost and overspool the poor little GT30 and only stop when the turbo bearings catch on fire. hopefully that would put me in the upper 400s...
blah blah blah so New Plan is to try to polish this thing up a bit and bolt it on. Let's hope no dramedy ensues with that process because I want to go for round 2 of dyno tune next week. I have never taken the intake off with the engine still in the car. I am afraid.
Got the intake welded up today, port matched, smoothed out some and shined up a bit. I put it on my car and it did a wheel stand right away! Here is a pic
Next I gotta do a log and see how AFRs are affected.
Also, I think I am going to let this IM be the harbinger of my new engine bay decor. I'm going to go for black, silver, and gold. This should look better than my old scheme of black, black, black, black, black, and purple.