Quote:
Originally Posted by damnslowtsi
I like this one since I like unconventional parts in general that you don't see on hundreds of other cars. I have a question for you guys, how much do you think is lost in performance by not using a bigger throttle body? I feel that it is kinda a waste of money to get a SMIM flanged for a standard size t-body even though some folks have made really nice power with them. Another question, what is the plenum volume on this manifold or how does it compare to other known brands like Magnus/JM race? Do you have any pics of the inside of the plenum?
|
Well, in the circumstance of using the Mitsubishi TB flange on this SMIM, it was designed this way so I could be used on the most 4G63's out there with minimal modification to be used. There really are not that many people using aftermarket throttle bodies on their current setups, and there are also very few people using 3" or larger IC pipes on their setups. Most of the intercooler pipe setups out there for the DSM's use a 2.25" or 2.5" IC pipe setup. This flange is ideal for most of the cars out there, along with their horsepower levels. A 52mm 2G throttle body is 2.0472", a 60mm 1G throttle body is 2.3622". An aftermarket 70mm TB is 2.7559", 75mm is 2.9528", and a Q45 TB 90mm is 3.5433".
In my circumstance, I am running 2.5" IC pipes from the turbo outlet to the FMIC, and the FMIC to the TB -- there is absolutely no need to run a 70mm+ TB -- could there be a gain? Sure. Could the larger TB increase throttle response? Sure. Could it also decrease spoolup? Of course. I have no need to run a Q45 throttle body. If anything I might see a few HP gain -- I am not expecting to see more than 15-20HP over my 1G 60mm TB though -- and I AM making nearly 1000HP.
I cannot give you a number on the plenum volume. I didn't build it -- if you want that question answered, talk to Luke at Beyond Redline.
As for more pics, here you go! I took an additional 16 photos showing the dimensions again, along with inside the plenum shots. Please understand that my manifold is USED, and just sucked up a turbo compressor wheel, so please understand that the stuff in my plenum, would not be found in your clean plenum (compressor wheel debris).
I did a quick 5-minute hand-polish on it also using Mother's Ultimate Billet aluminum polish and cleaned with a microfiber towel.
Quote:
Originally Posted by 1gDSM4g63
It all depends what your goals are and how big of a turbo you have to determine the size of a the throttle body and the plenum size you need.
Larger plenum and bigger throttle body is best used on a big turbo and a drag built engine like twicks69's car which gain 100hp+. However if you have a 16g a SMIM is the last thing you should be thinking about. A bigger plenum and throttle body hurts the spool rate. It's please self-explanatory in the first post of the dyno results.
And about your question in comparison with JM Fab and Magnus I doubt anybody know that. As mention in the posts above we are wait for FFWD test results.
|
As you can see from the dyno data taken on the first two test vehicles (Car #1 and Car #2), they were not losing spoolup whatsoever over the competitor's SMIM.
As for mine, we saw about a 200rpm loss, but we also had several other variables that we were dealing with -- such as the turbo. I also explained thoroughly the variables causing spoolup differences in the article == go back and read up if you missed it.
As for the large plenum design, we were able to prove that it was still beneficial on three different setups and displacements of 2.0 and 2.3L, with small to large turbos.
I would definitely say that the Beyond Redline SMIM made a strong difference over my old manifold due to the larger plenum and runner design. The 2.3L needs more air, and this manifold definitely produced it! Along with increasing my fuel injector efficiency.
Finally, you don't need an aftermarket fuel rail, ported head or an aftermarket throttle body to make 1000HP. The stock stuff works just fine. Can you make more power over the stock stuff? Sure, but at what cost? Some of the parts are extremely well designed on our motors, and only need a few tweeks to really put down some high HP numbers. Using a stock fuel rail with a -6AN feed and return and a set of 1000cc injectors along with a walboro 255HP in-tank and a walboro 255HP in-line fuel pump will support 1000HP all day long. The stock 1G head can flow it no problem also. I would say that gains are made though when changing over to oversize valves, and cams larger than 272/272's, but that gain was less than 30whp in the big picture.
The car made over 100AWHP more on just an intake manifold swap--that is a heck of alot better bang for the buck than purchasing an aftermarket throttle body along with 3"+ IC pipes, a ported head with oversize valves, and huge cams.