: Forced induction on the SRX



conedoctor
05-16-13, 06:55 PM
So I have been wanting to boost the SRX for some time now and I want to move the project ahead a bit, looking for good intelligent conversation.

That being said please don't post unless you can add to the topic.


I searched on the topic and the threads I saw on the STS forum were all no but no one had any facts or reasons why, just no. So please no blanket stupid statements.


I have full control over my ECU so that is not an issue, the CR is 10.5:1 so I will be aiming for like 5lbs. Not looking to build a race car just something fun and say it can be done.

The remote mount turbo would be a good choice but I think the supercharger will be my preferred route.

repnatl
05-16-13, 06:57 PM
Didn't the australians have a project blower on a 3.6 cts not sure if its in production yet

conedoctor
05-16-13, 07:48 PM
Ok but what does that have to do with supercharging a 4.6l Northstar?

repnatl
05-16-13, 07:56 PM
Lol forgot you had the V8

Mr. Mohr
05-16-13, 09:25 PM
Conedoctor, you read my mind. I've been looking into it a bit also. So far as I have found, the only REAL difference between the LH2 and the LC3 is the bore and compression ratio. So far as I can tell, the factory LC3 supercharger should bolt up ok. I found one on eBay for about $900. I'm not ready to jump into it yet, there are other (less exciting) things to take care of first. But I agree that a few lbs of boost should be fine on stock internals. I'm not sure on hood clearance, but I think the cts-v style "power dome" as GM calls it, would look great on an SRX. I want to pick up a spare hood to experiment with making an OEM looking power dome. CHRF is the only company I've found that has experience supercharging the N* at all. They may have some good advice, or they may tell you that you must do a lot of unnecessary upgrades to be safe. I'll be watching this thread like a hawk.

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PS- I don't know what numbers your thinking of, but I think around 350 to the wheels would be fantastic....and achievable.

1BadCadSTS
05-16-13, 09:32 PM
The lc3 sc will bold directly to the lh2 no problem. Timmyc bolted a lh2 intake on his sts-v when switching to a turbo set up.

conedoctor
05-16-13, 09:36 PM
I'm sure the LC3 has other differences but were not too worried about that right now, we have the LH2 so lets deal with it.

Not worried about clearance under the hood yet, I will measure though and see how close stuff is.

Lots of boosted northstars in the world but all the old ones so far that I can see, other than the LC3. I was going to contact CHRF and will at some point.

From what I know the smaller bore was to improve the head gasket sealing area to combat failures, this is one of my concerns but not a huge one, at 5lbs she better hold together.

As for the engine breaking I really doubt it is going to fail in that way, just head gasket or studs, I need to research the late model LH2's and see if they suffered form head tread failures.

Mr. Mohr
05-16-13, 09:51 PM
I heard it was mostly just the pre-2000 motors with the gasket and thread problems. I believe you are correct on the reasoning for de-boring the LC3, then again, the sts-v puts out about 495hp. I don't think you're thinking those kind of numbers considering we're talking 5lbs.

Whiplash_89
05-16-13, 10:28 PM
I would love to do this too some day but its my winter car/DD for hauling my kid and dog. I honestly think you could buy an ebay turbo or any used 50 trim turbo and bolt it up. Use the STSV injectors, ebay intercooler, cutom downpipe with cutout, you would need a custom manifold(s), and some dyno time. Its very doable. Only thing is that it would be fully custom. I think parts would be around $1500 without labour. I would be scared about the transmission though.

Mr. Mohr
05-17-13, 12:03 AM
Other though of course is a full sts-v LC3 swap....but that's another realm.

conedoctor
05-17-13, 01:36 AM
I don't think there is room for a turbo under the hood, you can't build a decent turbo system for $1500, you can barely get a good turbo for $1000 lol. I think the stsv supercharger is the way to go, I need to figure out if I can spin the blower slow enough to make my boost, I will call Eaton tomorrow and find out the minimum rpm I can turn it.

orandaberg
05-17-13, 06:20 AM
Hi
I had the same idea sort of here is a letter from Tim Carroll

The space in which the SRX has, limits your options.
The next thing to understand about the engine you have?
The intake design was engineered for maximum air intake, in other words there is no such thing as a electric
tuirbo charger that can put out as much air as your design already takes in.
When you added your Volant CAI you now have unrestricted intake, so you have max intake with its design.
This actually has a slight increase in HP and in fuel economy, not a lot, but a little.

Back to the limited space and using a forced air induction.
The exhaust turbo charger is not feasable in the limited space of the SRX without an expensive proffesional reconstruction
of the enternal body.
This is something that not only is way too much money! But would require a shop like ours that have the ability to reconstruct
the inside.

The only forced induction you could install that would actually give you an extreme HP gain is a intake Supercharger,
these types of forced air is an expensive add in, but they are an extreme high performance modification.
If a Supercharger is somethiing you would like to buy and have shipped for you to mod yourself, I could sure hook that
up for you?

The other things you could do to increase HP gain is a new header exhaust system, using high flow cat, high flow resonator,
high flow mufflers.
Also, to unleash the computer from holding it back, this will seriously increase HP and max your fuel if your not always putting
your foot into it? LOL

Your computer is not to be messed with and if anyone told you they could get into it and mod it, be weary.
All you need is a high performance chip with new maps that reconfigure your computer from the outside.

Mr. Mohr
05-17-13, 08:24 AM
Hi
I had the same idea sort of here is a letter from Tim Carroll

The space in which the SRX has, limits your options.
The next thing to understand about the engine you have?
The intake design was engineered for maximum air intake, in other words there is no such thing as a electric
tuirbo charger that can put out as much air as your design already takes in.
When you added your Volant CAI you now have unrestricted intake, so you have max intake with its design.
This actually has a slight increase in HP and in fuel economy, not a lot, but a little.

Back to the limited space and using a forced air induction.
The exhaust turbo charger is not feasable in the limited space of the SRX without an expensive proffesional reconstruction
of the enternal body.
This is something that not only is way too much money! But would require a shop like ours that have the ability to reconstruct
the inside.

The only forced induction you could install that would actually give you an extreme HP gain is a intake Supercharger,
these types of forced air is an expensive add in, but they are an extreme high performance modification.
If a Supercharger is somethiing you would like to buy and have shipped for you to mod yourself, I could sure hook that
up for you?

The other things you could do to increase HP gain is a new header exhaust system, using high flow cat, high flow resonator,
high flow mufflers.
Also, to unleash the computer from holding it back, this will seriously increase HP and max your fuel if your not always putting
your foot into it? LOL

Your computer is not to be messed with and if anyone told you they could get into it and mod it, be weary.
All you need is a high performance chip with new maps that reconfigure your computer from the outside.

The chip they recommend looks bogus, MadTuner is the only company in the states I've found that offers anything SPECIFICALLY for our SRX. Some people on the forum have used them with great results. But Cone said he already has the ecm taken care off.

Whiplash_89
05-17-13, 09:12 AM
I don't think there is room for a turbo under the hood, you can't build a decent turbo system for $1500, you can barely get a good turbo for $1000 lol. I think the stsv supercharger is the way to go, I need to figure out if I can spin the blower slow enough to make my boost, I will call Eaton tomorrow and find out the minimum rpm I can turn it.

What do you mean minimum RPM? Its always turning whenever you give it gas. V8 will have zero issues being able to turn it.
I think you could easily find a USED kit for a f body/mustang or something thats V8 from the forums for $1500.
I like the idea of this and I hope you do go through with it, but it will be expensive and you will break a few things along the way.

orandaberg
05-17-13, 10:00 AM
The chip they recommend looks bogus, MadTuner is the only company in the states I've found that offers anything SPECIFICALLY for our SRX. Some people on the forum have used them with great results. But Cone said he already has the ecm taken care off.

I believe the mail was sent to me before Madtuner had a tune?

conedoctor
05-17-13, 11:15 AM
What do you mean minimum RPM? Its always turning whenever you give it gas. V8 will have zero issues being able to turn it.
I think you could easily find a USED kit for a f body/mustang or something thats V8 from the forums for $1500.
I like the idea of this and I hope you do go through with it, but it will be expensive and you will break a few things along the way.

OK think about it, the RPM of the blower determines the boost pressure (sort of) but I need to underdrive it (I think) so I don't make too much boost but I don't know how slow I can turn it and the blower still be efficient. I can't just turn it super slow as it may not work.

Whiplash_89
05-17-13, 11:44 AM
You would just use a bigger/smaller pulley. SCs have almost instant response since they don't rely on intake/exhaust to make boost. Crank turns regardless, but even though its always turning it doesn't mean it making boost. So depending on the size of the pulley; thats what would determine when the boost creeps up and how high it goes.

conedoctor
05-17-13, 12:08 PM
Yes I get that but your not taking into account the efficiency of the blower, it would be awesome if things were 100% efficient.

You can't always just turn things faster or slower, at some point you need a bigger or smaller blower, since this is based on the STS-V unit I need to figure out if I can slow it down enough to work right, if you end up bypassing air in the supercharger itself you just make heat.

Whiplash_89
05-17-13, 12:39 PM
I'm still not really sure what you mean by slowing it down. But if you understand what you're talking about then more power to you. As I said, I hope you figure it out and follow through.

glake89
05-17-13, 01:36 PM
Wouldn't the SC supplier be able to tell you, based on engine CFM, tune etc.? If they don't know, who would?

conedoctor
05-17-13, 02:11 PM
From the info I have found so far at 10,000RPM we have 90% at 5000RPM it goes to about 75%, from what I can see at 2000RPM the blower turns 4200RPM and at 4000RPM the blower at 8400RPM (obviously) and 12,600 RPM if I stand on it.

So by guessing I need to turn the blower 1/2 speed for half boost (not correct but a starting point, 4.6 is bigger and blower efficiency goes to crap) the blower barely works and will just be wasting power, this is a guess and it may all work just fine but may use more power than it makes or close to.

I think a smaller blower turning faster is the way to go, but I will find out.

In the end the CR may just be a bit on the high side to make it work well.

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Wouldn't the SC supplier be able to tell you, based on engine CFM, tune etc.? If they don't know, who would?

We are basing everything off the STS-V blower, so I have to contact Eaton as they are the OEM.

Mr. Mohr
05-17-13, 06:02 PM
From the info I have found so far at 10,000RPM we have 90% at 5000RPM it goes to about 75%, from what I can see at 2000RPM the blower turns 4200RPM and at 4000RPM the blower at 8400RPM (obviously) and 12,600 RPM if I stand on it.

So by guessing I need to turn the blower 1/2 speed for half boost (not correct but a starting point, 4.6 is bigger and blower efficiency goes to crap) the blower barely works and will just be wasting power, this is a guess and it may all work just fine but may use more power than it makes or close to.

I think a smaller blower turning faster is the way to go, but I will find out.

In the end the CR may just be a bit on the high side to make it work well.

----------



We are basing everything off the STS-V blower, so I have to contact Eaton as they are the OEM.

I know the STS-V makes more HP than the XLR-V (I think about 20-ish) I'm not sure if it is simply from tuning or possibly from a slightly larger diameter on the S/C pulley. Something to look into perhaps. If it is a different pulley, that may help base some numbers at least.

conedoctor
05-17-13, 06:43 PM
I'm sure it would work but not sure how well and how, I am going to move on from this for now and move my focus back to headers for now.

Mr. Mohr
05-17-13, 09:41 PM
I'm sure it would work but not sure how well and how, I am going to move on from this for now and move my focus back to headers for now.

Carroll Cadillac?

conedoctor
05-17-13, 11:56 PM
No I am making them.

Mr. Mohr
05-18-13, 09:24 AM
That's probably best since it seams that nobody can actually get a response from them about their headers. Good luck with it.

orandaberg
05-18-13, 06:58 PM
I believe I asked this question about headers to Tim Carroll member. He had a project he was installing custom made headers. Have you tried his website? From past views I think he had pics of the engine project. He is a member an will answer emails pretty reqular.