Hey guys, Im doing alot of upgrading soon here and Im just woundering if you had the chance would you go with the 18G or a Big 16G? The reason why im asking is because im looking at ether getting a 16 or a 18. Please let me know what the better is for my buck! I will have alot of upgrades FMIC,injectors ect ect

Chris

I believe the 18G comes in several different combinations. If this is true you have to be careful about what you're buying, since each one might be different.

A big 16G, on the other hand, is a standardized part, so you always know what you're getting.

Flow rates @ 15psi:

Small 16G: 505cfm
Big 16G: 550 cfm
Normal 18G: 600 cfm (not the Greddy)
Normal 20G: 650 cfm

If they are similar prices and the same housings I'd go with the 18G over either 16G.

If there's a significant price difference or if the 18G in not the bolt on type just go with the B16G as the performance won't be that much less.

an 18G with a TD06 7cm turbine side is supposed to be a pretty decent turbo, probably even better if you put a TD06 compressor housing on it.

The compressor wheels on the Big 16G, 18G and 20G are the SAME with the exducer being 2.680" for all three. The difference between the Big 16G, 18G in comparison with the 20G is that the 16G and 18G are trimmed more which reduces flow and efficiency. The turbine wheels on both the Big 16G and 18G are the same (TD05H). Price wise your better off with the Big 16G as it's roughly $250 U.S. cheaper than an 18G. Big 16G is a much better value in my opinion.

Thank you everyone who posted! I have made up my mind and am going to go with the Big 16G. Thanks Paul, Mike and Blake for your awesome info!

Chris

Whoa Paul, back up the truck, TDO5 is the series of the turbo's including the housing's, not the wheels that are inside of it...and the 20G uses the TD06, a totally different turbo completely . the wheels are not the same but trimmed but different diameters totally
inducer 16g 1.83 ex 2.36
inducer B16g 1.89 ex 2.68
inducer 18g 1.93
Good choice with the B16g though, few are dissatisfied until they wish to go bigger...
Just make sure that the B16G is a true B16 with the 7cm housing, and not a 6cm housing with the B16 gut's stuffed inside.

Tim,

I will make sure to look very carefully. I want my car in the 12's, once its there, no longer do I really need to upgrade. I dont want to get to stupid with my daily driver

Chris

Hey Tim, it's air brake certification time !
Those compressor wheels (Big 16G, 18G, 20G) ALL have the *same* exducer. I forgot to put the "big" in 16G in one sentence in my post. The comp wheel in the TD06H-20G turbo is the same wheel that you've given dimensions for and for which the B16G and 18G is trimmed to. I was establishing the relationship of the wheels not the housings. FYI, the original "20G" turbo's were hybrids utilizing the smaller TD05H Compressor housing and smaller turbine wheel found in the TD05H series turbine housing .

I could get really stupid and go 20G, but I think thats to big.....Hmm Not to sure:P

Chris

20Gs are usually considered a bit large for a daily driver. They may lag considerably more than a small/big 16G.

also have a look at the small 16g. They are more efficient, and for the small flow increase, you might loose out on the efficiency. Plus the small one spools quicker. It produces cooler intake charges as well due to the better efficiency. But you have a front mount so that might not be an issue to you.

I second to that. I almost bought big 16G but changed my mind after doing some research. For my needs the small 16g was a better option. Read this article to get started.

http://www.dsmtalk.com/forums/showthread.php?s=&threadid=57986&highlight=Big+16G+sucks

A very good read here
http://www.teamnabr.com/ubbpub/ultimatebb.php?ubb=get_topic;f=5;t=002233#000001