Maybe they are saying the lnf intake manifold does not work, which is true, it does not fit.

 

I actually read through your thread shortly before your post. Maybe I missed it but I don't see where you said what gasket to use? What turbo are you running? The point of cutting out the divider in your manifold was to combine the gas pulses and increase your spool time?

 

Looking on eBay cracking the LNF manifolds appears to be common? There are several with cracks for sale. What's the deal there?

 

This is the thread where they are saying the LNF exhaust manifold does not fit the LE5.

https://www.cobaltss.net/forums/2-4l...-2-4-a-148270/

 

Well Slowbalt has one that fits perfectly. So like I said in that thread it's wrong.

The divider was removed to increase flow, but that decreases spool, but the KO4 spools so damn fast it doesnt matter. The cracking is extremely common of the divider, its thin cast that sees extremely high temperatures

 

Thanks, I just ordered a manifold on eBay and am about to call BNR back to order the tubo.

Anyone got any suggestions on wastegate control or BOV's? I prefer a BOV that doesn't vent to atmosphere. I find that noise annoying.

 

Ottp sells the exht gasket its the copper one

 

You wont need a bov. The turbo has a bpv and wastegate built in.

 

BNR says I'll need a hi/low manual boost controller and that the 2871 does not have a BPV, so I'll need an external ...

 

If you use the LNF manifold you just need to use the gasket from your engine, not the LNF one. I had an issue with an LNF gasket on a LSJ head leaking.

Curious as to what you're putting the engine into. Sand rail?

Exhaust manifold: on ebay, a nice cast one, not shitty china welding
http://www.ebay.com/itm/Garrett-T25-Flanged-Manifold-2005-ON-Cobalt-2-2L-Ecotec-Engine-GT2860RS-GT28R-/380866481275?hash=item58ad694c7b&vxp=mtr
This company is local, they offer a cast stainless one, and i've seen it installed, it's gorgeous. Call them, they will be of more help than some of these other companies.
https://www.treadstoneperformance.co...Turbo+Manifold

 

That is a really nice manifold by the looks of it but I did actually buy an LNF manifold and the BNR turbo today and I think they should be able to get my 350 bhp and then some.

This one isn't mine but is an example similar to what I am building. It has an LSJ at 350hp:


Ecotec rigs are fairly rare in the rock buggy world. I think mainly because of the difficulty and expense of adapting longitudinal transmissions to them. V8's are by for more common, specifically the Gen III and IV Chevy engines. This is the last one I built and recently sold. It has a 400hp LS2 in it. (Linked because its a large pic.)

http://patooyee.com/wordpress401/wp-...907266_HDR.jpg

It was the 4th ground-up build under my belt. It weighed about 5400 lbs without me in it and had rear steer. It was a bad beast but when I started building it I was single and during the build I got married and had a beautiful daughter. They do not ride with me and I want to down-size the hobby as a result. So I am hoping to keep the new rig under 3000 lbs, as close to 2000 as possible. It will also have rear-steer. (I'm a rear-steer junkie.)

 

At 5400lbs that's a big rig for sure.

I'd guess with the gearing you use for the slow speeds involved it doesn't really matter, but with almost as much power and half the weight, it should be very fun.

A big blower setup on an ecotec would give that nasty, V8 torque powerband and still be much lighter/smaller. More money than a turbo though.

 

My bad. Youre right

I use the hallmam es mbc but any hallman controller is fine.

Idk about bov, all preference really

 

Part of the challenge of building these things is keeping most of the stuff fairly tame because it could get destroyed and need to be replaced at any minute. With that in mind, before I even started this project, I went to a Pull-a-Part where I had seen two M90's in the past and pulled them. I figured if I destroyed one I would just pop the other on. After learning about boost, airflow, and pressure ratios though I realized that the M90 wouldn't work for the 2.4L. I also wasn't crazy about using 10% of my power to simply drive the blower. Any other blower would be expensive to replace, difficult to source. That's when I started looking into turbos. The guys already running them were getting such great results it was hard to argue with the efficiency.

Rock "crawling" has evolved greatly. A lot of it is go-fast now days. I wheel in the southeast where traction is always hard to find because rocks are covered in mud. That means a lot of the time you are bouncing off your rev limiter. Truth is that I spend only about 50% of my time at slow speeds. The other 50% is either racing down trails or steep hill high rpm assaults. When you're at 7000rpm with no traction and suddenly catch a dry spot or tree with one tire it sends a huge shock load through the drive train. That's where having too much power can test the durability of your parts. 350 bhp seems to be the happy point in buggies like I am building where reliability is acceptable. That is why I have tried to resist the urge to get as much power as I know Ecotecs are capable of. At 350 the new rig will have a higher power to weight ratio than my old one so I suspect I will have all i can do to learn how to drive it at that power level. Any more will just be dangerous and break stuff.

 

After researching boost controllers the primary purpose that I can tell in having a multi-stage or electronic controller would be to increase fuel economy when max power is not needed. Being that I couldn't care less about fuel economy I think I'm just going to go with a cheap, reliable manual control valve and call it a day.

 

Yeah for your use a simple mechanical boost controller is perfect. I use a Hallman MBC on my turbo tercel and it's more than enough.

 

Anyone have any suggestions for turbo intake manifolds? I'm looking for a log-style. The stock manifold gets in my way.

 

I think turbo tech racing and hahn have made one, not sure if they still stock them. How does the stock manifold get in your way? Just wondering because the TTR and Hahn one extends further perpendicular to the matting surface than stock does

 

Hm ... that might be an issue then. I sit right next to the engine and the stock manifold is in the way of my arm & elbow. I was going to fab my own intake to address it but was hoping that someone might already make one.

Is there a reason that log-style is so popular? One that looked more like a traditional exhaust header would actually work even better for me. Then I could put my TB and intake wherever I wanted.

 

Wait are you talking about the intake manifold or the exhaust manifold?

The log style intake and exhaust manifolds are so popular is because of the easy of construction and general applications they can cover, vs a purpose built equal length tubular manifold. Also it's a lot easier to cast a log style exhaust manifold than a tubular.

 

Intake. I just used the header example as an visual queue.

I'm used to fabbing custom headers. If there's no performance issue in designing something similar for the intake that might be what I end up doing.

 

I'm sure there is some gains in sizing the ports for the air velocity depending on where you want the power, but equal length from a air plenum should be fine

 

Yeah if the stock one is an issue i dont think there are any smaller ones

 

Maybe the saab lk9 manifold

 

Looking at the LK9 I do not that that would work any better than my current manifold.