Small displacement engines and huge turbos.
 

Explain something to me because I am probably mis-understanding something.

I am browsing a local forum and I read these threads where people boost their nissan spec v's and honda civics. Sub 2.0l engines. They strap big t3/t4 SC61 turbos to them left and right. I have done some googling and these turbos are good for like 600+hp.

Around here we put big turbos on our cars, but from what I see they arent as big as the ones the honda guys are using. I think the biggest I saw here and least common is a GT30, more common then that GT28 and most common GT25.

What I dont understand, is the spool on these turbos as bad as I think it is or do these configurations actually produce some sort of useable torque curve?
I just dont see the point in strapping a huge turbo, to a small engine, and not even making the power it was intended for.

I could be wrong.

And having it power the front wheels.
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They live their life a quarter mile at a time.

Sam you're not wrong...but you have to think about the people you are talking about. These are the same people who thought 3 foot tall wings on the back and flimsy-a$$ body kits make a Honda look driveable. Granted...there are some Honda guys who know what they are doing...but they are probably scratching their head just like you and I.

At my old job...my boss had a 90 Civic with a built 200HP motor - then a turbo on top. (so he knew what he was doing). I was explaining one day why I made a bi-turbo setup on my A4 using a small turbo with a quick spool-up and then a larger (sequential) turbo for maxium effiency. I swear to you...you would have thought I told him the earth was flat. Some people get it...some people don't.

I've wasted alot of time watching car videos. I've seen a bunch of hondas make huge power. Takes forever to spool, and doesnt last long because they run out of revs. So for that few seconds they are haulin' ass! and then they have to shift and wait for spool.

Which is good if you like to go fast, then spin loose the tires you use to turn.

Edit: you edited while I was posting so Im editing after you edited

I know someone did a bi-turbo with their miata but has anyone done big and small?

Tim has twins. It might be a space issue to do a larger one though.

didn't he sell that setup? I think another member on here has them now. Some people think the bigger the turbo the faster they will go, let them waste their money.

Ok. Good, cause I was worried they knew something I didnt.

most honda guys I know use insanely large turbo's. first of all the vtec b/k series revs to 8-9k rpm, so even with shitty 5k rpm spool you still see a good 3-4k of boosted power. said the cars are mainly used for drag racing and street racing. Usually the cars run some pathetic times (unless on slicks) but trap ungodly high speeds. On one of my rsx's I had a peakboost gt35r turbo kit. full boost was by about 4800rpm and I could take it to 8600rpm all day long. Wasnt a fan of the powerband, but on the highway "from a roll" I was king. LOL

That's your answer. The badass honda's with big turbos can make power to 9k. I mean it. Like at 8500 power is STILL climbing. Their motors are amazing. So they can put a turbo that doesn't spool till 5K because they still have a 4000 RPM powerband of full boost. If we miata folks put the same turbo that spooled at 5K on a B18, it would spool at 5500 on a miata, and the miata's engine is done at 7K. No power band.

Granted it's in a fail wheel drive car so the usefulness of 600fwp can be debated. :giggle:

and have 9500RPM rev limiters.

Its all in the head. The miata cylinder head doesnt flow nearly as well as a B-series Honda, or, dare I say, even a good D16 VTEC despite it having one less camshaft. Ergo, the Hondas can use larger turbos with better spool than if you used that same turbo on a B6 or BP.

But I still think a T4 on a 1600 is retarded for street usage.

That explains a lot more. I didnt realize the red lines were so high.

When I saw his car a couple months ago it still had them.

There's also many of us who don't understand how so many people can live with less than 300 rwhp. I would sell my car if it was that slow.

The honda crowd uses big turbos because their buddies use big turbos. Endless cycle.

I still have my twins (parallel GT1548). I sold the original GT1544 setup to Paul but one turbo was destroyed on his drive home so I took it back and made the first absurdflow manifold instead. I redid the TT manifold for two GT1548's and still don't make the power or torque he does.

The current TT kit, actually my entire drivetrain for that matter is for sale for the right price (not sure what the "right" price is yet). I'm thinking it's time for a 302 swap.

There IS room for a sequential TT setup (I think there's more room than the parallel setup). I had all the parts purchased (going to use a 2554 and 56 trim .86AR 2871) and a manifold designed for sequential when the deal with Paul happened.

I was basically going to put the 2554 sorta where FM/BEGI places theres, and the 2871 below and behind the manifold, sorta where I hope to put it in the upcoming A/C & P/S friendly Absurdflow manifold.

I'd still love to do it if someone had the coin...

Hehe, I'd love to do a setup like that too. Well, I'd want a compound setup, not a sequential. A man can dream, right?

LSx though if you do a V8 swap. Cost more, but would be better. I've got a hot 302 and I'm probably gonna part it out. If I ever did a V8 swap for something, it would be LSx or a modular ford 4.6.

ohhh compound...there ya go haha.

LSx's are hard to beat for sure, especially with all the new companies making kits and FM doing their typical fantastic development and documentation. But I may have access to an aluminum 302 block, I want to built it myself (whereas with LSx it'd be dumb not to buy a GM Crate engine and harness), and I want to use the AEM ECU. AEM makes a nice distributor-replacement CAS for the 302; I'd try to run two miata 1.8 coilpacks instead of a distributor. Actually this route would most likely cost more than a LSx swap :( so who knows.

The ford explorer/mercury Mountaineers had a distributorless ford 302 from the factory. Strongest block ford ever made for the 302 BTW. (comparable to a BOSS 302) It's THE engine to build for a ford 302 platform.

But yeah, all the little stuff is why I said LSx. By the time you get a 302, and do this and that, etc etc, you'll have a ford lsx equivalent with more time and money in it. And now you can't buy a million parts for it cause you already have. :) I have a 302 that was making about 400hp. It was a blast in my T-bird, but that's all it would ever do on pump gas. And it didn't idle well, or get good mileage. And it needed a forged crank because the ford cast cranks SUCK. Building a 302 is 1500-2000 alone. LSx looks more and more appealing..

I was going to say the same as 18psi and Pat said already. Why choke off an awesome top end with a relatively tiny turbo? Most of the turbo Honda crowd races on the highway, where they can use the power. It wouldn't make sense to turbo a Honda for autocross, for example, because that would automatically put you in at least SM, against much more powerful cars not limited by their drivetrain layout.