Injectors, manifold, transmission

A

AnFu

New Member
Hello!

I really don't know how to start this, but here it goes.

I have a RS13 with stage 3 CA18DET currently running around 300whp with H-dev chip. And now I have a few questions for which I was looking answers for a long time, but unfortunately I haven't had any luck or everything got me even more confused.

This is the basic stuff I am having done to the power plant:
-Stage 3 H-dev chip
-Z32 Maf
-FMIC
-T28r turbo (S15)
-444cc injectors
-2 3/4" exhaust
-ported head
-Vic reinz MHG
-NKG BKR7E sparks
-257 lph Walbro fuel pump
-Original 5-speed MT
-Kaaz LSD 1,5-way
-ACT clutch with DW lightweight flywheel

Everything runs on 1,25 bar of boost and 100 octane fuel.

As far as I have read everything the engine at this stage is mechanically capable of running 450 BHP safe.

I am about to restore the turbo and uprate it with larger and lighter compressor part so it can run safely to 1,8 bar with less lag.

1# Question: How much power can an OEM exhaust manifold hold? Will it hold those 450 BHP or should I build a new one with less restricting flow?

2# Question: I don't believe that the stock MT would be capable of holding that much power, especially if the is some clutch kicking involved. What kind of transmission can be mated with as low as possible modifications and can handle that kind of power, and what would the modifications be?

3# Question: Since the turbo is being uprated, I was thinking about raising the boost pressure and removing stock FPR and than raise it also. Or at least removing this 444cc injectors and replacing them with smaller ones. So I would have higher FP with smaller injectors, therefore better mist and better cooling of the engine with fuel (at least that's the theory). Anyhow this would be kind of an analog tuning like in the old days without computers. Fiddling with pressures of air and fuel while monitoring A/F gauges.

Anyway, the most desired answers are for Q #1 and Q #2, the third is just for your opinions and advices.

I hope you have any good suggestions and that you understood what I meant. My English has gotten a bit rusty.

Best regards, AnFu
 
#1 Probably no-where near 450 BHP, 300+ is tried and tested but not that much more.
#2 no the gearbox will probably go bang, what is your idea of little modifications
#3 Just no, you'll need much, much larger injectors. 720cc or bigger.
 
1- There is no way that engine can reliably hold 450bhp@wheels or even at flywheel. Turbo won't get you close either. A stock ported manifold is proven at 350bhp+ though.
2- It can, but it will break sometimes. I would stick with it and only change it once it starts breaking often.
3- You will need much bigger than 444cc injectors for 450bhp regardless of pressure.
 
I knew I forgot something... I also have forged internals.

So for the #1 there is everything OK if I leave stock manifold till 350bhp somewhere.

#2 As minor modifications I meant: replacing bell housing, clutch disc... I would like to keep the flywheel, clutch cover, driveshaft and diff the same if possible. I had something from RB (GT-Ts) in mind, but don't know if it will fit.

#3 I've seen some dyno graphs (I forgot if I can paste a link of a dealer/tuner), with the same turbo at 1,7 bar but with 510cc injectors running at 2,8 bar to get 380whp (I guessing around 420-430 at the crank). I know 450 Is a bit much. But lets say, if I rise the fuel pressure to about 6bar (new rails and everything), and teh boost pressure to 1,6 bar.. I think it's possible to get at least 350whp. And this Hp is the least of my concern, I will get some decent mapping done and new injectors, but for than I would like to have a reliable transmission and manifold that will hold 450bhp.

I know there are a lot of things possible if you are willing to fiddle with everything for a bit of time, I will post the results when I will have the build done.

Btw, does anyone know or have experience with Tomei parts for the head (at least cams and springs, I won't rev the engine over 7500rpm)?

And thank you for previous answers.

Best regards, AnFu
 
What??

You want to run 6 bar fuel pressure and 1.7 bar boost pressure, honestly it's just a shit idea.

You'll smash the turbo to pieces very quickly and I can't see why you'd wanna run such mad pressure instead of getting appropriate sized injectors in the first place.
 
When I bought the turbo the Garrett guys said that the safe (maximum) line is till 1,8 bar boost pressure and since the turbo is being rebuilt I don't believe that is going to be a problem. The "mad" pressure idea came from some guys that tune VAG vehicles. They run from 5 to 8 bar fuel pressure to get better atomization and artificially raise the octane level. As I said power gains from this setup are the least of my concerns, the main things that I still don't know are which MT can be used for more power and what EXH manifold (something to buy or better made it by myself).

Thank you for your concern.

Best regards, AnFu.
 
Each set of injectors is going to atomize fuel pressure better at certain amounts... Just because that's what they use for pressure doesn't mean that will work best for you. I would get some 750-800cc injectors... And use a normal fuel pressure. Just my $0.02
 
If you wanna run 1.8Bar pressure then go ahead, you'll probably figure out why you're one of the few that do it.
I'm not saying it won't work, I'm saying it won't work for very long.

Also you can't 'rebuild' a T28R like you can a journal bearing turbo.

You can replace the CHRA unit, and the housing but thats about it.
The cost is often so close to the price of a new turbo it's often not really worth it.
 
Hello again.

I figured out the next things.

I will build custom transmission for my car (stronger gears, different ratios).
For now I will use the stock EXH manifold, and if that won't work I got some connections at a company that makes cast iron (same material as stock) products and will be another custom made item for this car.
About the fuel injectors and pressure. I will go with the 444cc as they are now. But with custom mapping, and higher boost and fuel pressure.

I will update you when the thing is going to run :).

Best regards, AnFu.
 
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