Turbo 240 or 300

Ramian17":z0zxsqvr said:
Went and told him 202/202 114° . So which turbo lol

Garrett or Borg Warner?
You mentioned that your machinist prefers BW.
The new Garrett are less money.
Either one will do the job.

The propane engine is in the makings but a good wideband turbo will push 5000 rpm even if full boost is at 2000 rpm.
What is unknown is if the Turbine housing A/R is .64 for low rpm boost will the engine choke before 5000 rpm.

Conversely if the A/R is .84 can it make big boost at 1500 rpm.
The 300 six is a fairly big engine and I think there should be enough exhaust volume to work both ends with an .84
Turbine housings can be changed if the results need fine tuning.
 
Yeah he liked the BW turbos probably im going to go with them? Personally I have no idea on the housing AR? Wow it can be changed without replacing everything? That's nice. No joke I'm not going to push this motor past 3000Rpm. I drove it all day no higher than 2500 only went to 3000rpm when passing or racing lol. Everyone laughs and says I will take it to 5000rpm now that I can. I always could but that's just plane scary. Going to 3000rpm in third or second gear is flying in the old girl. 75mph third gear 55mph second gear she's geared pretty high in my opinion. I just want her to have more pedal/power at 2500. Basically in third gear going down the highway. And also boost before 1500RPM I think is a good idea. It had loads of torque by 1250rpm and even 1000rpm honestly it was in a strong power band by then. Either way I'm going to go with your opinion on the turbo. Thanks again for your help. I was just curious what is your back ground with turbos and these motors how do you know so much!?!?!
 
Ramian17":376dig1g said:
Yeah he liked the BW turbos probably im going to go with them? Personally I have no idea on the housing AR? Wow it can be changed without replacing everything? That's nice. No joke I'm not going to push this motor past 3000Rpm. I drove it all day no higher than 2500 only went to 3000rpm when passing or racing lol. Everyone laughs and says I will take it to 5000rpm now that I can. I always could but that's just plane scary. Going to 3000rpm in third or second gear is flying in the old girl. 75mph third gear 55mph second gear she's geared pretty high in my opinion. I just want her to have more pedal/power at 2500. Basically in third gear going down the highway. And also boost before 1500RPM I think is a good idea. It had loads of torque by 1250rpm and even 1000rpm honestly it was in a strong power band by then. Either way I'm going to go with your opinion on the turbo. Thanks again for your help. I was just curious what is your back ground with turbos and these motors how do you know so much!?!?!

Well that makes turbo choice easy.
The Borg Warner EFR 6258-A
It is their 49mm ball bearing turbo with a .64 A/R turbine housing.
It is also their smallest turbo in the EFR series but it will still support 350 hp at 15 lbs of boost.

I have experience with 2000+ hp twin turbo engines in NHRA Top sportsman and 10.5" tire outlaw classes.
Also 2000 hp multi stage nitrous engine and presently Vintage 7 liter blown alky Hydroplane.

I took on the 300 six because i always liked the inline six and I love to see sixes kick V8 butt.
 
Haha I like your confidence. I just googled that turbo it looks super awesome and amazingly clean. I love it. I am also a little worried about such a tiny one. It looks like it is mostly put on 2.5 to 3 liter engines. Can you change the housing very cheaply? In doing so allowing it to breath better if it chokes out?
 
The turbo size has to do with engine airflow.
A 3L engine at 6000 rpm with good breathing heads will outflow a Ford 300 six (4.9L) at 4000 rpm with very bad breathing heads.

Yes The .64 A/R is because of the low rpm you want to have boost available.
There should be no chance of choking the engine if you don't care to run the engine much above 3000 rpm.

The BW EFR turbo has internal wastegate and internal bypass valve which means you won't have to purchase an external wastegate or a blowoff valve.

Jegs has the best price and the 126 page instructions is also there if you would like to take the time to read through it.
Click detail on the product page, then click on the instruction tab.
 
Awesome he's going to port and polish the head so hopefully it flows super good. Yeah 3000 in the old girl is all we need. I need way more power and torque below that rpm. How much power you think this motor will have at 2500 if she is making 10-15psi? And yeah it is super handy about the waste gate and blow off valve.
 
If the head will flow enough to get the engine volumetric efficiency up around 80% then it should make about 430 ft lbs with 10 lbs and 500 ft lbs with 15 lbs @ 2500 rpm.
That would be 205 and 240 hp @ 2500 rpm respectively.
Disclaimer: Your actual results may vary. LOL

The EFR 6258 supposedly comes with the 179283 canister that controls the waste gate between 12 - 18 lbs of boost which would be too high.
The 179282 canister controls up to 10 psi by itself and can be controlled between 10 - 15 psi by using a controlled spill valve.
 
Yeeeee haaaaaa I like those numbers!!! Don't worry I totally understand that results may vary. I won't get mad at you if those aren't the exact numbers lol. Is there anyway to make sure the head flows 80℅? So you think I should go with the 179282? I honestly don't think I will need to turn it up to 15psi but once in a blue moon especially if your 430ft/lbs prediction is accurate!!!!!!! Why is there such a large margin between torque and horsepower at only 200?
 
So I read the first 50 pages of that instruction manual. It said that twin scroll housings are better for spooling faster for low RPM. To get that you have to go the B housing Which is the .84? You still confident on the single scroll .64 housing?
 
Ramian17":10mnfhp6 said:
Is there anyway to make sure the head flows 80℅?
The port work needs to focus mainly in the bowl area around the valve guides.
The ports walls only need a cleanup without making the ports larger. this will keep velocity high at low rpm.
Here is a good example presently being done by golfmiser
viewtopic.php?p=588394#p588394
You may hit 80% could be a little more with the header and long runner intake.
What size valves will be used?

Ramian17":10mnfhp6 said:
Why is there such a large margin between torque and horsepower at only 200?
Horsepower = RPM x Torque/5252
Ramian17":10mnfhp6 said:
So I read the first 50 pages of that instruction manual. It said that twin scroll housings are better for spooling faster for low RPM. To get that you have to go the B housing Which is the .84? You still confident on the single scroll .64 housing?
The twin scroll housing for the 6258 is a .80 A/R just to be picky.

I know the single .64 will work. It has a small T25 flange which is restriction to high flow. I wish it was at least a T3 flange.
I don't know if the .80 B housing will give you the same low rpm result because I don't have any experience from me or others to draw a positive conclusion.
It may work just as well at low rpm while providing more upper rpm power at the same time. It uses the much larger T4 twin scroll flange.
You will get boost at low rpm just don't know how much.

I personally would go with the twin scroll housing and plumb header tubes 1,2,3 to one side of the scroll and 4,5,6 to the other side.
I would bank on the fact that under the load of 3rd and 4th tranny gear, the 300 six will produce enough exhaust volume to get plenty of low rpm boost.
(I don't like giving away horsepower)
Also need to remember that if you try get too much boost at too low of an rpm, the turbo can be driven into the surge zone.
You are in uncharted territory because most of the time the person is looking to make horsepower and not worried about off idle torque.
 
The intake is 1.6 and the exhaust is 1.94. I honestly dont know which housing to go with. I'm going to keep reading and asking questions lol. I like the B housing. I personally have no idea if the motor would be pushing enough volume at 2500-3000 with the B housing. I'm sure there is a chart? I only have a three speed so when she is is screaming it's usually second and third. I would say your right I probably honestly don't need much improvement in power at the super low rpm. The van had a 240 and in first and second gear she had way more power obviously. I wouldn't think much more is required to tow what I want in first gear....Around town. It's the upper second and mostly the upper third gear where I need some more go juice when she is loaded down super heavy up hills aka interstate on ramps those....fun things.
 
The 300 will certainly have enough exhaust volume above 2000 rpm to get full boost with the B2 housing.
The only question was how much boost between 1000 and 2000 rpm.
If any amount of boost below 2000 rpm will work for you then go with twin scroll housing.
It may also help to keep the turbo out of the surge zone at low rpm.

You will want the low boost canister for that housing also.
I can show you how to make an adjustable spill valve so you can vary the boost.

It looks like you know a lot more about turbos then you did a few days ago. LOL
 
Oh yeah I like it. Cheap too lol just with in the budget. I still hope it will make a little boost below 2000. Correct me if I'm wrong but I read that these motors are still mean machines with only 5-8psi. Also isn't this one still sized for a motor smaller than mine? So hopefully she will spool up fast. Yeah I'm learning slowly but surely. I can't thank you enough for your help I would of been screwed without all of your advice. What is a spill valve another valve on the wastegate?
 
I checked the Dollar Store but didn't see one there. Oh Well

The 300 six does indeed makes a lot of torque at low boost levels so any boost at low rpm will make the van roll along very well.

The line from the internal wastegate canister connects directly to the intake manifold. The spring in the canister holds the wastegate closed.
As boost increases, at some point the pressure in the top of the canister will overcome the spring and opens the wastegate to dump exhaust.
There is some adjustment in the linkage between the wastegate valve and the canister to adjust the spring pressure but as you shorten the link to increase spring pressure the travel is decreased so the wastegate valve cannot be opened the full amount.

A spill valve goes in the line between the canister and the intake manifold.
Its job is to bleed off some of the pressure going to the canister so it will take more manifold pressure to open the wastegate valve.

It can be as simple as a "T" with an adjustable needle and seat. When the needle is closed no air is spilled and you get normal boost.
As the needle is opened air is spilled reducing the pressure to the canister and the boost level is increased.
The only other addition is a one way valve in the line so when there is a vacuum in the intake manifold there will not be a vacuum leak which will mess with the idle rpm.
 
Gotcha sounds like it is going to be some fun piping work. If by some miracle we pull his thing off and she is making 12psi at 2500 and a mean machine at that rpm. Then most likely will she be making 5psi at 1500, giving here considerable more power than stock? Obviously they are made up numbers and a huge hypothetical. But do turbos work that way or do they just basically need a certain amount coming in and once they get that they go from basically nada to whatever you have your boost set to? So the spill valve allows you to boost higher than the internal wastegate is set? I need this because my wastegate is going to be set at to low of a boost level?
 
The reason for spending the money on a ceramic ball bearing, low inertia, twin scroll turbo is to have full boost buy 2000 rpm or even before.
I can tell you from experience that the EFR turbo will begin to spin as soon as you hit the engine starter. Our twin 88mm turbos did.
Combine that with a cam that makes peak torque around 2000 rpm and there should be more than 5 lbs available at 1500 rpm.

It takes a certain amount of energy to compress the air to the target boost level and also overcome bearing friction.
The time to get there (accelerate the turbo wheel) is based on the amount of inertia the wheel has along with bearing friction.
If the engine is producing enough exhaust energy to meet those needs then target boost level can be achieved.

When you are in high gear the engine speed doesn't change very quickly and the load on the engine allows exhaust pressure to build to a high level to drive the turbo and also give the turbo time to catch up to engine flow requirement at target boost level.
In low gear at WOT the turbo is chasing the rapid change in engine speed and may never reach target boost.
Here is where the low inertia and low friction pays off again by allowing the turbo to track the engine more closely resulting in higher low gear acceleration.
Hope this answers your question.

Yes, the purpose of the spill valve is to allow you to adjust the boost level above the baseline set by the wastegate canister so it is important to have the baseline below the boost range that you want to use.

If I remember correctly The Holley HP EFI has a safety boost limit that can be set in case the wastegate control has a problem like the control line from the intake manifold is off or damaged or some other mishap.
 
Back
Top