juggernaut1

The Borg Warner s300sx also seems to be a very capable turbo spooling similar to a GT35. I note the BW s300sx's are available from Full-Race at just over $1,000 US. Here's a comparo on an Evo 2 litre and 2.3 litre. http://forums.evolutionm.net/service-parts...roll-gt35r.html

Liz Not sure whether this forum is providing the assistance you are seeking as it is a case of "he said", "she said" and only you and Trent knew what was actually said (or wasn't said). Without playing legal eagles generally the courts will seek to restore the plantiff to the position they were in before the defendants negligence be it through their action (or inaction) especially where they hold themselves out to be an expert in their field. This means that you would have to proove that Trents alleged negligence or contributory negligence resulted in the damage to your engine. If you are successful in proving that then the Courts would generally order Trent to restore you to the position you were in prior to the alleged negligence or contributory negligence. Therefore, if you started out with an engine that was 90% worn he would only have to restore you back to that position. Whilst its no comfort to you - you will end up spending more in legal fees than the cost of rebuilding an engine or finding a second hand stock engine. Moreover, I doubt you will find a lawyer/solicitor that will guarantee you any success on the matter. You would also more than likely need to find an expert witness (engineer etc) to support your claims in court. Case in point - my brother had a V8 stroker motor built and it never even clocked up 100 klms before it through a rod out the block and two pistons vaporised into every orrifice within the engine and engine bay. All brand new part were returned to scrap. Whilst he suspected that the engine was built with incorrect tolerances (too tight) how was he going to prove that unless he spent the next 2 or 3 years of his life and earnings over that period finding an expert witness to convince the Court. He just put it down to experience and bought another engine from another supplier.

That is one way to do it....but not the best way. Geoff at full-race found there is stronger pulse energy by utilising two separate gates as he found there was a small discernable "leakage" from one gate tube to the other under the single gate method.

Typically I see GT35's with the wastegate welded on the turbine housing with the 6Boost manifold - I guess this placement must assist the wastegate perform its task - was yours done in this fashion. In any case if you go twin scroll you will be using two gates which should alleviate any boost related issues you've alluded to with the 6Boost.

Correction - you will need to run two external wastegates - one for each bank of collectors which feed into each scroll of the turbo. Like this sr20 manifold:

Yes, that dyno print out was with a T4 TS 1.06 rear. Incidently, that WRX set a lap record with that setup - stock bottom end also. And in doing so also outgunned the new R35 GTR. If a 2.5 litre subi can develop that sort of torque at those rpm I'm guessing the TS 1.06 rear would be well placed on an RB26. And if the WRX results could be duplicated on an RB26 I don't know why you would bother with a smaller rear housing IMO. But thats the beauty of twin scroll - you can run larger than normal housings and not suffer slower spool like that of an open housing.

Further to the above - if you are considering a FR manifold you may want to confirm whether it is a straight bolt on fit for you car. I'm fitting a FR TS manifold to my s15 and I've had to have a bracket made up to lower the aircon compressor 30mm and have had to relocate the power steering resevoir further around the strut tower and make up new ps lines. The 2 gates are also an extremely tight fit. I also had to open up the flange plate on the manifold to match to the exhaust ports and tidy up the manifold collector a little with a die grinder. If I was to do it again (or the manifold cracks) I would give Kyle a call at 6Boost to make me up a manifold as it would also suit the right hand drive layout whereas the FR manifolds are primarily designed around left hand drive cars. Having owned both types of manifolds (but not tested both) I prefer the 6Boost manfold as the flange plate is the correct size and the tube welded onto the flange plate on the 6Boost manifold is flared to suit the port flange size. My 2 cents

Deceive, This is what that setup goes like on an EJ25 (Subaru 2.5 litre). 442 ftlb by 4100 rpm and 496 hp at 6500. Sounds good to me. And this is what it looks like.

Yes, I realise the housing is an ATP modified verions of the GT32. Geoff also initially thought that the .78 was too small for the 3076 too but everyone in the US is running them on their SR's now including himself. I'll have my own Full-Race TS 3071 SR20 example up and running in the next week or so. Moreover, given that Str8e180 (on this forum) is running that ex housing with a GT35 on a RB26 and is knocking on the door of 400rwks (and possibly more once his fuel pressure is sorted) doesn't indicate that there is too much of a restriction in the modified GT32 housing up to those power levels anyway.

Why not a 3071, 3076 or GT35 in twin scroll they all use the same .78 divided housing albeit the housing is machined out for the larger wheel of the GT35. That way you can setup your manifold and gates to suit that housing and have the option of 3 turbos. Full-race also puts together a GT35 on T4 divided ex housings for more flow if that is necessary. From memory .82 divided housing are also available for the 3071/76/GT35 but harder to come by. I think Billett turbos may have them available tho.

Must have been some lame HSV's you drove. I drove a run of the mill VS Commodore from Perth to Sydney in sixth gear virtually all the way with the cruise control set at 117klm's/h last year with no deceleration you speak of.

I agree, my brothers twin turbo VZ hooks up increadibly well even with coilovers all round.....and the broad spread of power and torque is fantastic.

Have a look at the link to Lewis Engines in this thread. Now look at the pics on the site of the chamber for the SR20. Now Look at their RB head. In stock form the RB head is smilar to the SR20 head. You will note that the RB chamber is round. The SR20 chamber is not round but has straight edges in the chamber running down its perpendicular. This formation essentally forms a quench pad in that on the upward stroke of the piston the pad compresses the mixture into a smaller volume into the middle of the chamber right underneath the spark plug and in doing so is said to aid swirl in the cylinder for a more complete burn. Others argue that the pad - due to is straight ridge it forms in the cylinder - increases the basis for a 'hot spot' under compression leading to detonation. If you look back at the other thread Shanef posted up a little while ago with pics of his JHH head you will note that JHH doesn't remove the pad but they lay it back towards the cylinder wall in a way that takes away some of the sharpness from pad. In this way they have attempted to keep the pad to keep up swirl in the cylinder but have modified the pad in an attempt to remove the potentional for detonation the pad can cause.

If that pic of the RB head in the Lewis engines link is anything to go by it seems they remove the quench pads. Meaning your chamber volume will be increased. So you will find you drop comp if your not building the bottom end to suit. May want to confirm chamber volumes are the same or near the same as stock if your putting the head back on an already built bottom end and not going to a thinner head gasket.

Here's my brothers APS kitted twin turbo VZ running just under 8 psi (no boost controller) - showing before and after turbo power and torque figures. Please ignore the hand drawn lines - we were comparing another motor. If you really don't like the alloy block you can get the LSX block.

What I find more amazing is that you can push 400rwkw's throught the .78 divided ex housing. I actually didn't think it would flow that much. Good to hear because I'm putting that ex housing on a dual gate divided manifold and running a 3071 for now (on my sr). Least I know I can throw on a GT35 with that housing (albeit machined out to suit the GT35) without having to get a new manifold made up for a T4 footprint housing.

Yes, Will ported my head too and my discussions with him was the motive for the larger ex valves too. I also had lengthy discussion on whether to completely remove the quench pads in the chamber.....which they modify rather than completely remove like Mazworx in the US does.

I agree with what you've said on the basis you've assumed a constant mass flow rate. The issue is at what point do we need to improve the mass flow rate because it becomes a bottleneck in which case larger ex valves are required to ensure exhaust gas residue in the cylinder doesn't overly taint the fresh incoming charge. The answer to this question will be dictated by the intended application, rev range etc. I tend to think boost and intake manifolds will take care of the intake side of things to a point. Returning back to my backyard porting I installed larger flat back and narrowed stem intake and ex valves in my Pinto motor with no loss in torque through the mid range and good hp gains throughout the rev range. Incidently, I recently had my SR20 head also done by JHH and also went with 1mm oversize Supertech inconel ex valves. The port and chamber modifactions largely resemble the pics of RB head in this thread. My build is nearing completion so I can't comment on the affects of the head work at this time.

I've done a bit of backyard head porting on my old 2 litre pinto powered rs2000 based on books from David Vizard on these motors (I made twice the rwhp with stock rejetted carby, inlet mani and aftermarket cam with same duration as stock). Based on his testing its the shape of the ports that dictates flow and velocity rather than the shear size. From memory he said it was the quarter of an inch before and after the valve that was most critical. Also wouldn't the larger exhaust valves and ports enable the exhaust gasses escape more quickly (one less bottleneck) and hence result in less exhaust gas residue in the cylinder....thereby reducing the possibility of detonation and/or being able to run more advance to assist in earlier spool. My 2c

Not directly on point but when I asked Mark at Mazuroski at Mazworx in the US about whether to use Eagle rods or Manley Turbo Tuff rods in my SR his email response was: "Anything over 400hp we like to use the Manley's". My take is that cheaper aftermarket rods will hold a decent hp.....the question tho' is for how long.

For what it's worth I got Race Torque Engineering in Wangara to recently build my SR and they got Performance Modifications to do my machine work including installing Darton sleeves. But I haven't started it yet so can't make a valid recommendation yet.

Str8e180's setup with GT35 with ATP .78 divided housing on a divided manifold and you get this:

Str8e180 had a twin scroll .78 ATP housing on his GT35 with one of his own divided manifolds. From memory it ended spitting out around 380rwkw.

Younger brother runs the twin turbo version of the 1JZ in his 83 Celica Supra. Those turbo's may be tiny.....but lordy does is develop some useable torque - awesome street engine especially in a 1280kg car....and literally screams to the redline. Only mod is running twin dump pipes of the turbo's and integrate them into the 3 inch exhaust under the car.