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I had no idea big singles had gotten easier to spool...2500rpm??

anyone care to give me a little primer on the latest singles that can crank an easy 800bhp and spool quicker than 2530s?
First step is to throw that standard crank away. Stroke the bastard! :D
 

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WMI wouldn't be needed with E85, and I suspect the 8374 on E85 would be sufficient for that power and happily outs pool the 2860s.
Prob true, but hunting for 800hp and quicker spool, big cubes and the 9180 would be my choice, after seeing my 8374 proform on the RB30 with BP98

.....now to get the 1.05a/r and some E85 :nervous:
 

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Discussion Starter #25
yep, thinking 800hp crank. although if I could get an honest 800hp at the wheel with spool at 2500rpm versus the 4000rpm it took to wake up my 2860-5s, I'm all for it!

also cool to hear there's a quality 2000cc injector - I can replicate part for part the fuel system on old Moby Dick and just use the bigger injectors so that I can map for E85.

Buying toluene in bulk in the USA gets you red-flagged by the police, because you're either making methamphetamines, or trying to make TNT! Running toluene in Korea was cost efficient because it was the same price as petrol. But with petrol prices so much lower in the States, E85 is the best option.

Thanks for the info on the singles! Glad to hear that turbo technology is still advancing. Because steady-state highway cruising is a necessity here in the States, I've ruled out twins and therefore even the slimmest chance of turbo shuffle.
 

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Well if you are only thinking 800 crank HP, Then with a similar setup to mine (just go for the 1.05a/r hotside) and add E85 I would say you would be there.
 

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What do you mean by spool at 2500rpm? With the likes of the EFR you will get boost at 2500rpm, but not full boost. It won't really be pushing you in the back until 4000rpm or more still - it'll be better than the GT2860Rs, but not like a supercharger either. If you want full boost at 2500rpm and a bunch of power then you aren't realistically going to do it with turbocharging - its going to need a supercharger, and maybe a turbo as per the title haha. You'd be better off with Subboy's RB32DET + EFR turbo (not sure about the 9180, that'll make 1000+hp on E85 haha) - simpler, more guaranteed to work and just generally brutal.

For what it's worth the EFR8374 is proven to be capable of over 700whp on E85, the EFR9180s are still rare as hens teeth but to be competitive with it's peers it'll need to be capable of 850-900whp on E85.

Is this on an R32? You'll probably need to change a few things to make it E85 friendly, and be quite generous with your fuel pump setup too.
 

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i've made many compound setups, turbo turbo and turbo supercharger. Celica, Supra, MR2, 3000GT, now doing S2000. Let me know if you want some pointers.. I can post pics if I'm not too lazy today, dynoed a twin fuel engine until 2AM and woke up at 6AM... not enough sleep....
 

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Personally, I think RB30 is the way forward on this.
You can get VERY good response out of the modern big single turbo already.
It will probably be a more efficent and less complicated system.

And lets face it... even my old 88HTA running on a 2.6L have very good response.
Not massive torque at 2500rpm, but I never went out of my power band on track either.
I can only imagine how much an extra 400cc will to that.
 

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Discussion Starter #32
if compound charging will be too difficult, then I suppose one of these new singles would be fine...an EFR8374 making an honest 700whp, yet hitting full [email protected], well, 2860-5s would reach full boost at the same point, so that doesn't sound all that bad!

the Skyline sickness...we approach an engine build plan with a practical mind, then all that goes right out the window chasing a bigger and bigger hit when the boost comes on song :)

There's always nitrous to help things along. I now live in a place where nitrous is heavily used and hence a lot of experts around to do an installation that won't blow me to pieces :p
 

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I'd go V8 for sure. The chevy LS engines are so well supported in the USA, you'd end up with a better result AND an easier build. I bet it would be cheaper too.
 

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I'd go V8 for sure. The chevy LS engines are so well supported in the USA, you'd end up with a better result AND an easier build. I bet it would be cheaper too.
How would you keep the front diff with an LSx? Surely (practically) impossible.
 

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I'd go V8 for sure. The chevy LS engines are so well supported in the USA, you'd end up with a better result AND an easier build. I bet it would be cheaper too.
if I can keep the front diff, that may well be viable. LS builds are quite cheap in comparison to most other builds here in the US and you can get quite a bit out of a supercharged 5.7 liter!
 

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And so my thoughts have gone again towards the Group B solution - compound charging. And it does make me wonder why it hasn't been done (or done more often). I want to run a bigger single, one in the 800bhp range, but remembering how much 2860-5s can lag, I'd like to see if something can be done about that.

So the straightforward idea is to stick a Rotrex supercharger where the power steering pump is, and feed that directly into the intake of a T04z, T88, or whatever the latest and greatest single turbo is these days (never did keep track of the single turbo model numbers). An Eaton blower would develop boost quicker, but a Rotrex would be easier to plumb.
As others have said, if you can get what you want from larger capacity and a single turbo that's got to be the simplest approach.

First, a disclaimer: I've not got any experience of twin charging, though I have given it a fair bit of thought on and off.

My first thoughts are that if I were to do it to my own car, I'd not be looking at a centrifugal supercharger. I would have to ask whether it's lag or boost threshold you're trying to reduce. Like I say I have no direct experience but to get a good spread of torque from low down you're going to want a positive displacement blower, not a centrifugal, so either roots or lysholm based. My personal preference would be an Eaton TVS if I could get hold of one but I don't know whether you can buy them separately as I've only ever seen them as part of a kit. My reason for preferring the TVS over the lysholm is that in my understanding, when freewheeling (ie being driven but with the bypass valve open) a roots based blower would draw less mechanical power than a lysholm type (because AIUI the lysholm is still compressing internally).

I would also get the turbo to blow into the supercharger, not the other way round. If the supercharger blows into the turbo, you have to ensure you've got a high flow blower bypass valve that will open as soon as the turbo is ready to suck more air than the supercharger is trying to push out else you gain little or nothing from the turbo. This of course would be more of an issue with a fixed displacement blower than a centrifugal, but you wouldn't want the restriction of an under-blowing Rotrex choking the turbo inlet either.

I think it's still a good idea to be able to short circuit the supercharger when the turbo is fully on song, reduce parasitic losses.

If you do use a fixed displacement blower, be careful with your plumbing as I fully expect the throttle bodies will be after the supercharger in the air flow. Fixed displacement blowers don't really like trying to blow against closed throttle plates.

I'm looking forward to finding out how some of the others on this thread have done this. No doubt what they've found to work well is exactly what I'd say I wouldn't have tried myself!

Cheers,
Kingsley.
 

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celica st205 I did with a GT40 and a mercedes / eaton M62 (with electric clutch)
Hi,

Did you find that there's quite a big pull on the belt to bring the blower up to speed when the clutch engages? If so, how did you work around that?

I've often wondered whether this is a problem on systems that dis-engage the blower at higher engine rpm and then suddenly need to engage it when the engine speed drops to, say, 3000rpm. Suddenly engaging a blower cluch when the engine is doing 3000rpm would cause quite a yank on the drive mechanism.

Cheers,
Kingsley,
 
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