I have a few questions here. Would I want a twin 58 mm throttle body, or would I want a 52mm its currently a stock motor but I want to make it into something more, its my daily driver as well gas mileage does not matter.

Also will this need tuning once a new throttle body is put on, or can I get away without tuning it?

Any idea on hp gains?

Its a 1994 z28 around 118,000 on it.

And the last question what one is better between these two, or which one would I buy?

http://www.jegs.com/webapp/wcs/store...hTerm=129-1544

http://store.summitracing.com/partde...5&autoview=sku

 

The stock throttle body people say is good to 450rwhp. On a stock car withouth a CAI I really dont think it will give you any power. I would look to invest in a CAI then catback before going throttle body.

 

So your thinking cold air intake first then exhaust instead. I was also thinking the same but was wondering if maybe the Throttle body would be better, but as it seems maybe not. I have seen cold air intakes from 50$ to 250$ Is there a reason there is such a high difference, im sure there is just would like to know what. Links would be nice aswell to some good known one's, from what I know all they consist of is a wider tube and a k&n filter (or whatever you perfer) Any more info would be appreciated.

 

The reason it is pointless to have a aftermarket throttlebody is becuase if you have a stock airfilter/airbox, it is your bottleneck. The throttlebody is after that. I have a K&N CAI and it is nice. On that page are more different manufacturers as well. Then the theory of balancing the in with the outs a free-er flowing exhaust is next. Headers and Catbacks here... After that go with a heads/cam setup. Then you should be contemplating a throttle body IMO.

 

Its been quite a long week, and I completely agree with you that I definently need to work my way in from the out, so I see your points and there right, its like haveing a 4 cylinder exhaust on a v8, and putting bigger pistons in it.(example was kind of overkill) So are the more exspensive CAI better then the cheapo on's like on ebay?

 

Im sure the theory of "you get what you pay for" comes into play here. IMO id go with Moroso, K&N, SLP or something along those lines.

 

I think ill grab the K&N they have a real good reputation, and prices arn't to bad. How much of a difference do you notice if any with a CAI?

 

K&N says 17rwhp. I dont know how true that is. I bought my car with my CAI and Flowmaster on it already. I like the K&N alot. The Flowmaster sounds nice but people tell me it is restricting... If I had the money I would go with the GMMG like Moshbmx1. That is the best sounding catback I have heard IMO.

 

Ok, thanks for all info, Im going to bed now worked 40 hours past 3 days im whooped.

 

You don't have to waste time waiting for responses if you have more questions about CAIs (home-made Vs. eBay Vs. SLP Vs. etc...) -- you can try searching and will learn more than you want to.

They are all the same - Moroso, K&N, SLP - gains are arguably the same.

Go with Moroso if money is tighter, K&N if you you will feel "better" about it and SLP if you prefer NOT to have the CAI plastic (SLP is probably the better looking of the three IMO). Some disagree because either they like a more "stock" appearance or they hate black metals.

There are other things you can find if you search (e.g. some say the SLP since it is metal gets too hot....some say it doesn't.....some like the metal....some people put bags of ice over the SLP CAI to cool the metal before racing.....anddddd etc).


SUMMARY: just choose the one you like best - it's pretty widely accepted that there is no real advantage with one over another.

 

Well, while on subject of CAI, what do you guys recomend for an exhaust, id like it to sound good but have quite a bit of hp gain. As long as its lound im ok with it for the most part. Also what type of headers might you recommend?

 

SLPs is nice - might wanna go for the Hooker if you hear the SLP LM on a stock car and think "that's the perfect loudness - no louder" - a lot think LM is too raspy after headers.... sorry this gives you literally no information, once again - do a search - there's so much out there to read that you will miss if you don't search for it because any small talk here can't possibly cover all the facts/opinions/etc

 

I installed the Flowmaster cat back on my car. I only noticed that it became louder.

But then after I put the headers on, it completely changed the sound of the car. It also gave it a nice little SOP (Seat of the pants) kick.

So, you'll probably get a much better performance gain out of headers than just a cat back. I was not able to feel any performance improvement with just the cat back. Also, now I find my cat back to be a bit annoying because it's kinda loud. The Borla sounds completely different and provides better performance when you take out the plate. But it costs about 3X as much.

 

While I was looking for cat backs all I found is completely kits, is there a way I could just buy the catback part? So I don't drop 380$ on some useless tubes that I can make myself?

 

Some manufacturers have a 3 inch pipes all the way back from the cat backs. Hence the name cat back. You can buy mufflers and have a shop weld them in that might be cheaper. But that would only be for sound though, the 3 inch pipe from the cat back would increase performance.