Internal Wastegate with atmospheric dump

[biglady112]

Ok. I just installed three on our 2G's. One is a victory performance, one is a punishment racing and the other is a home brew using a stock o2 housing.

I was just wondering how many of you have external dumps on yours. And if you do, do you like them? Did you notice any differences. My friend Andy thinks he might have spent $130 the wrong way. He doesn't think it works at all. He spools faster and now his car sounds like a mean DSM should. And still has stock exhuast with no muffler. Its a 2.5" exhuast tube withe 2" dump tube. no spiking at high boost like before. It hits and stays where it its suppose to.

Steve

[jmakado]

i think i would buy something else for $130. don't get me wrong, external dumps sound cool and work well for controlling boost creep. but i would use it towards something different (cams, dsmlink, etc.). that being said, i would take one in a second if it were free!

[biglady112]

it has HKS 264 cams and DSMlink. So thats why it was purchased. He cannot afford exhuast until the spring.

Steve

[KeltonDSMer]

I really like mine because I run a cat. It is just as quiet around town, but still flows plenty at full boost.

I do have a full 3" from the turbine outlet too, so I can only imagine how much of a difference it would make on a stock exhaust.

How is freeing up a major backpressure in the exhaust system at WOT in anyway a waste of money? I bet that it frees as much backpressure as a 3" cat-back on this car. A lot of gas is moving through the dump at full boost because there is so much restriction in the stock exhaust. The fact that he is running the stock exhaust with cams and other mods, makes the dump that much more effective.

It makes sense to me that the largest gains from an O2 dump would be seen on a car with a very restrictive exhaust system, (just like these situations).

[jmakado]

How is freeing up a major backpressure in the exhaust system at WOT in anyway a waste of money?
i wasn't saying it was a waste of money in any way....just that i would spend the money in a different way. steve mentioned that the guy already has dsmlink and cams. that is what i would have bought (or used the money towards). how about suspension, tires, other power mods? like i said, this is only my opinion, but i think that better times (more power/better hook-up) could be had for the money.....that being said, i would love an external dump for the mean sound alone!!

[KeltonDSMer]

I think the question is how much is the exhaust system going to be upgraded in the future? If is going to be a full 3" w/o a cat, the dump probabally won't free up much restriction, but it would be a geat Idea if just going with a 2.5" system or if you will be running a cat.

[Dallas J]

Im pretty sure if you ever want to compete in a street legal bracket or heads up race then you cant have a dump. Its a cheap way to get around a problem, and it works but has its draw backs. Most street legal races require you to have a full exhaust system that exits behind the driver with a muffler. If you have a cut out, or o2 dump then thats not a full exhaust.

I could be wrong though...

-Dallas J

[biglady112]

He has brand new drag radials, 2600 clutch, small 16g. SO we have everything pipes, MBC and everything to get this car going. Just needed to free up exhuast. I'll have him read kelton's post that way more than one person agrees. But he has 1G BOV, new brakes, fuel pump, 690cc, 1G fuel rail, SX regulatot w/ gauge. So this car has plenty done. Was on stock exhuast thats all. 4 layer head gasket, ARP head studs, ACT flywheel, soon to be Shepard tranny.
Steve

[jmakado]

He has brand new drag radials, 2600 clutch, small 16g. SO we have everything pipes, MBC and everything to get this car going. Just needed to free up exhuast. I'll have him read kelton's post that way more than one person agrees. But he has 1G BOV, new brakes, fuel pump, 690cc, 1G fuel rail, SX regulatot w/ gauge. So this car has plenty done. Was on stock exhuast thats all. 4 layer head gasket, ARP head studs, ACT flywheel, soon to be Shepard tranny.
Steve
that amazes me that he has all that and never upgraded the exhaust...any particular reason?

[biglady112]

Well he needed everything at different times. We never fit an exhusat in the budget. I just figured the dump would get us through. But as you know its always one thing or another so thats why everthing was done in a wierd order. Plus this a a super low budget car.
Steve

[KeltonDSMer]

You should flow plenty with the dump and no cat for a 16G.

Definately get rid of the cat if keeping the stock cat-back. I would gut or remove the muffler as well. It probably sounds like ass, but would certainly reduce backpressure. That's a good $50 spent.

I use a dump because I run a cat, I like being really quiet around town.

Just my $.02

[biglady112]

The car has no muffler and a gutted car. It sounds real funny at WOT but sounds kinda cool. We have a spare cat if he ever needs to put it in. THe car is registered in Elbert county. So no emissions are needed.
Steve