When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Just trying to play around with the EFR Matchbot to come up with turbo options for next motor. One of the guys at Full Race configured this for the 2.5ltr 8v motor when we were investigating the backpressure. http://tinyurl.com/ztvcqf2
So just trying to do a bit of playing about for the 3.2 16v motor by editing some of the specs but am not getting a totally even line in the 'Turbine selector sizing' chart. I assume the VE has something to do with it. I just bumped the figures up in each segment vs the 2.5 8v on the assumption that the worked 16v head will move more air than the worked 8v head...but perhaps that is too simplified an approach.
Anyone want to have a play at it is more than welcome. Once you open up the link above you can edit it yourselves. You can leave the engine rpms the same. Our intention is to run at less than 26psi just to increase longevity. More likely circa 18-21psi but we would allow for 26psi max for 'special occasions'.
After seeing Gustafs engine absolutely pushing his turbo, You could possibly go to a GTX4088R with a .95 rear housing with out seeing to much more lag.
Yeah, I was going to open up the Garrett can of worms too. But at this stage I'm just looking at the EFR range and that will entail new 4-2 headers, Xovers and larger than current 3" exhaust system.
I know Rod runs the largest of the EFRs but obviously gains a lot of benefit from the 180o head change. He was seeing full boost with that large turbo at approx 3300rpm which is amazing! I would assume we may have to go down in size from his as we also don't enjoy the benefits of the SQ paddle shift trans like his and Gustaf's. While we hope to be able to rev beyond say 7500rpm safely we will have the largish 94mm offset crank to develop some lower tq that we may need with the H pattern 'box.
Patrick,
Have you ever considered just using a centrifugal supercharger rather than a turbo?
Then you could really pick and choose where you want max boost, and the boost gain is pretty linear over the RPM range.
Yeah, I was going to open up the Garrett can of worms too. But at this stage I'm just looking at the EFR range and that will entail new 4-2 headers, Xovers and larger than current 3" exhaust system.
I know Rod runs the largest of the EFRs but obviously gains a lot of benefit from the 180o head change. He was seeing full boost with that large turbo at approx 3300rpm which is amazing! I would assume we may have to go down in size from his as we also don't enjoy the benefits of the SQ paddle shift trans like his and Gustaf's. While we hope to be able to rev beyond say 7500rpm safely we will have the largish 94mm offset crank to develop some lower tq that we may need with the H pattern 'box.
Only reason i mentioned garrett is i know a lot about them as i researched for mine....
If you want the EFR turbo, i choose the compressor on what you want out of your motor. say you want your 21psi at X amount of power, make sure the compressor can do that. Then choose the rear housing on data you have from rods engine and what ever else you can find.
For what it's worth, might be a good idea to bolt on your gtx3582r to get a base line for what it can do before buying a turbo.
Patrick,
Have you ever considered just using a centrifugal supercharger rather than a turbo?
Then you could really pick and choose where you want max boost, and the boost gain is pretty linear over the RPM range.
Not sure if you know what WTAC is, But using a SC will rob you of power before making power. and in WTAC you need to squeeze your motor for what it has because .1 of a second can win you the competition
Id expect you would want the 9180, we didn't gain that much by switching the head around, you engine will make similar power. if you make a new passengers (rhd) engine mount you can get the turbo lower and get a better run for the manifold, And as long as you don't make the pipes too big I think it'd work really well.
Not sure if you know what WTAC is, But using a SC will rob you of power before making power. and in WTAC you need to squeeze your motor for what it has because .1 of a second can win you the competition
Yes, it might cost 30-40hp depending on how hard/fast you are trying to drive the thing.
But you might gain that back by being able to use a better exhaust than one that has to feed a turbine in a tight engine bay...and also by picking the max-boost RPM range as desired.
I know that for all-out power purposes and max efficiency the turbocharger will win vs. a centri SC...but Patrick's not (presumably) aiming for 800+hp which is the ceiling for a number of the available units.
That said, I guess with a good EBC on your turbo it doesn't really matter.
Yes, it might cost 30-40hp depending on how hard/fast you are trying to drive the thing.
But you might gain that back by being able to use a better exhaust than one that has to feed a turbine in a tight engine bay...and also by picking the max-boost RPM range as desired.
I know that for all-out power purposes and max efficiency the turbocharger will win vs. a centri SC...but Patrick's not (presumably) aiming for 800+hp which is the ceiling for a number of the available units.
That said, I guess with a good EBC on your turbo it doesn't really matter.
No but when competing, especially the amount of power pushed though these engines (even though patricks doesn't seem like a whole lot, the dynos in aus are more conservative numbers than the US.) You need as much reliability as you can at your aimed power level.
A well sorted turbo is the best option he can go for, especially WTAC.
The VEs are definitely different, and VE is by definition a description of how much air the engine is pumping vs how much it could be. Here are a few VE tables I have. The first one is from my 8v 944, and the second one is a 944S. Both are NA so you'll have to excuse the fact that 50%+ of these maps are missing for you, but it gives you an idea of the areas where the 16v head picks up from the 8v. The Y axis is MAP in kPa. Take the numbers themselves with a grain of salt, I'm not sure what req_fuel the 16v map uses...but the trends are there.
Patrick,
Have you ever considered just using a centrifugal supercharger rather than a turbo?
Then you could really pick and choose where you want max boost, and the boost gain is pretty linear over the RPM range.
Not really Spencer. Pauly is pretty much right. For us the turbo is still the way to go. Unless you mean Twin Charge! Interestingly the builder gave thought to running the motor half n/a and half with forced induction. Interesting concept which we won't be pursuing.
Originally Posted by thingo
Id expect you would want the 9180, we didn't gain that much by switching the head around, you engine will make similar power. if you make a new passengers (rhd) engine mount you can get the turbo lower and get a better run for the manifold, And as long as you don't make the pipes too big I think it'd work really well.
How were you able to determine how much advantage (or not) the changed layout of the motor provided Rod? Did you guys just cnc a new mount in at PR or did Ariel make something up during the Intake process?
Originally Posted by odonnell
The VEs are definitely different, and VE is by definition a description of how much air the engine is pumping vs how much it could be. Here are a few VE tables I have. The first one is from my 8v 944, and the second one is a 944S. Both are NA so you'll have to excuse the fact that 50%+ of these maps are missing for you, but it gives you an idea of the areas where the 16v head picks up from the 8v. The Y axis is MAP in kPa. Take the numbers themselves with a grain of salt, I'm not sure what req_fuel the 16v map uses...but the trends are there.
Thanks for that Mike. The guy from Full Race turbo put in his own specs on that Matchbot site. He came up with the VE based on info I had sent him on that 8v head. That head has very large ports and oversized valves. It didn't go into choke on the flowbench. Even so, the modified 968 head will far surpass it in efficiency and flow. I don't quite understand how you work out the VE of a motor though. Surely it's not just flow numbers of the head.
We turned the head around for a better exhaust manifold, i.e. Shorter which gives better response;and to separate the hot and cold sides of the engine, so we could have lower intake temps. I don't think it necessarily increases the peak power much on the dyno, it's to make it quicker on the track.
The mount on the rp968 is just fabricated from steel, I'm intending to get one cnc'ed when I turbo my street 968.
12-03-2015, 06:56 PM
Turbo matching for 16v racemotor
