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Changing Rotrex Pulley 90mm to 80mm

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Been thinking to replace my 90 mm pulley with an 80mm one. Is this dangerous to consider on my stock engine externals?

 

Have spacer and ARP's installed to rods and head.

 

Running .8 nearly 0.9 bar of boost which Im told is quite high but the engine sounds and feels strong and contemplating using my smaller pulley for more boost.

 

Would I need a re map or should I just wait to build the other engine info a proper forge engine built to last kind of setup and then run the smaller pulley?

 

What sort of boost difference would it be? I think my 90mm is 0.9 bar which is about 12 psi, would an 80mm pulley be around 16/18psi?

 

Cheers

Rams

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I had a bit of a play last night and went home feeling a bit gutted! Put it that way! I went past him and waited for him to react and tried not paying too much attention to the rear view mirror so he wasn't thinking I wanted to race and before I knew it he had planted it and I was literally about to take my exit and thought I will give it ago and planted 4th and couldn't catch him! It was silly really as I backed off once thousands of stones sprayed my car and I was clutching thinking MY PAINT WORK!

 

But Yes John, I need more power!

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I'm ashamed to say!

 

---------- Post added at 12:20 PM ---------- Previous post was at 12:18 PM ----------

 

3 series bm, couldn't catch the engine detail but assume 330 - I've raced them previously but before the rado was charged and had no problems. It wasn't a fair comparison last night but I just felt I should have caught him quicker than I did.

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Dont be too disheartened, His must have been tuned, and he probably went home thing 'bloody hell, I had a 20 year old Corrado VR6 reeling me in'!

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Lol, I will get over it!

 

Is 16 or so psi too much? What weakens as a result of too much boost? Pistons/rings?

 

Most say 350 bhpish the engine can handle with the mods I've done so can I look at it that way or does it not work out like that?

 

Also, I have an adjustable boost re circ valve. I did ask Vince at the time if he needs to adjust it and I didn't really cover this part long enough with him but he said 'it was set up for Bobbys car the right way' but his engine/mods were different.

 

Does the adjustment dictate when to start boosting? Pressure of boost?

 

Can anyone elaborate on this kit? There's an adjustable spring or control with it, I can put the link up of what I've for if that's easier?

 

Also maybe a question for Bruce at Devils Own but we haven't adjusted the Meth controller, set as it was received and mapped to my engine. Is one adjustment for more meth and the other to progressively adjust how much is sprayed in?

 

Sorry for all the questions spanning off the pulley but somewhat related.

 

Power is knowledge and all that....

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Honesty mate you'll find more power will be wasted with out some form of cooling. The meth kit shouldn't be a primary source of cooling for the power you're after, more a supplementary cooling to a fmic or charge cooler.

 

That would be what I'd look at next as there is no point in upping your power without a proper cooling set up. You'll risk pre det and just loose all that power as the heat rises.

 

Also catch a car in the wrong gear and its hard to catch up. A sorted bm with near 300bhp won't be easy to walk over, you saw how our cars are and you have nearly 40bhp on my set up ands its still tight performance wise.

 

Plus I don't want you to knacker that bottom end as I need it for mine ;)

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Rams it would not be wise to run at 16psi with your current Spacer gasket (1 point drop in compression)...you would really need Forged pistons which will drop compression by 2 points or a Spacer gasket that achieves the same.

 

 

Is 16 or so psi too much? What weakens as a result of too much boost? Pistons/rings?

 

Most say 350 bhpish the engine can handle with the mods I've done so can I look at it that way or does it not work out like that?

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---------- Post added at 8:36 PM ---------- Previous post was at 8:34 PM ----------

 

[/color]

I'm ashamed to say!

 

---------- Post added at 12:20 PM ---------- Previous post was at 12:18 PM ----------

 

3 series bm, couldn't catch the engine detail but assume 330 - I've raced them previously but before the rado was charged and had no problems. It wasn't a fair comparison last night but I just felt I should have caught him quicker than I did.

As other's have said don't beat yourself up about it there are alot of quick car's out there. When i had my cosworth i had only had it a short time and came up against an evo i was destroyed however when i had upped the power to 330 i came across the same evo one night this time was very different i didn't destroy him but i got the better of him.I will add i had a set of light's in my rear view mirror as i pulled away from a set of light's in sierra and gave it some stick these light's hardly moved they were buzzing about behind me like a midge when i pulled up at the next set of light's i was astounded to see it was a starlet this was when there wasn't many about, i hadn't got up to a great speed before slowing for the light's anyway at that set of light's it was going on to a dual carriageway 1st and 2nd gear he was actually doing pretty well as soon as i put in to third :wave::wave: you will learn matey 300 odd brake means nothing against some of the cars out there but you are in a corrado that's what count's.

Edited by clumpy1

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Funny you should say about the starlet, I was out in a friend's GT a few weeks ago. Some poncy git pulled alongside in a 370z at the lights, and frowned as if to say "you got no chances!" We battered him off the lights, then did the same at the next set when he pulled up again with his angry face, revving like a good un! :lol:

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Funny you should say about the starlet, I was out in a friend's GT a few weeks ago. Some poncy git pulled alongside in a 370z at the lights, and frowned as if to say "you got no chances!" We battered him off the lights, then did the same at the next set when he pulled up again with his angry face, revving like a good un! :lol:

I have been lucky in my life with some of the mates i have had over the years one had a Regal Nova turbo with 6 speed box the lot it was savagely fast this was when there was only a couple of them about we had been out battering all comer's from the local modder's meet in Rochdale and were talking to a few people ans this young kid was like "I'll have a go against it" we were like ok this lad strolled over to a totally unassuming 4 door sierra with a set of rather poxy looking 5 spoke alloy's on it 1.6L badge on the back there was a couple of other car's came out which were quickly left we were doing a fair whack by this time then this sierra went past us like we were sat still.Got back to car park to be told it was running 450bhp cosworth power it was then i decided i would have to buy one which i did Cossie power is awesome ford build quality is shi** unfortunately.

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Lol, the lights thing reminded me of ' Meet the Parents' the part he's racing the Dad from each set of lights. Always makes me laugh!

 

Had we levelled and went for it then I'm sure I would have taken him, he was tanking it well before I knew and when I clocked that he dropped the hammer I was in 4th and thought I'd catch him. Sure he thinks he did a vr6 and that's what bugged me.

 

It's the first encounter where she came home with her tail between her legs. The day before I played against a civic type r and won easily so I was over confident, never a good thing.

 

Once I get that Go Pro camera I vow to show you all that the Corrado will be victorious!

 

Alex, good to hear from you, it was a knee jerk reaction and knowing my 80mm pulley would have given more boost/power it was easy to wish it was on.

 

I will be patient and forge the 2.8 that's sat in my lock up.

 

Those little jap things are fast, I had one all over me a while back, sat on my bumper, literally sat on it. This was before she was charged but they are little rockets to 80/100 mph.. Especially tuned versions.

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It was probably a 335i you encountered. Quick as standard but devasting chipped. Regular 330 petrol and diesels aren't that quick really.

 

Should have gone turbo :D

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Quietly saying this but think it was e46, just unsure if petrol or diesel? I will find him again to heal my physiological wounds. Lol

 

My Rotrex will be fine my friend, it made very food figures on Bobbies C. Just need to get the other engine built up and run in and then it can be pushed. Craig tells me the 94 charger is barely stressed with my set up so there's still more to come. You know the bit that dissuaded me from going Turbo was the exhaust manifold and downpipe mods.

 

Think both are great fun things to have and do give the big smile factor when you consider how old the car is but how well they respond.

 

For a guru like yourself I realise why Turbo is more appealing and what you can do with them tuning wise but you can't argue with strong figures from a simple design such as a charger. You can tell from my reply even though you were just having some banter but it was a difficult decision. One i had been cogitating about for about a year or so.

 

But that day Craig went past me and the sound it made just instantly flicked my eye balls into pounds signs and ended the decision right there and then. Then the following day or 2 days afterwards, I read, 'Rotrex charger and engine etc all for sale' and everyone spoke highly of him so I couldn't refuse. Just wish I had more funds to have bought the engine and charge cooler/short runner. Wouldn't have lost to that Bmer then!

 

I blame it on running 99 Ron when the car was mapped for the upgraded V power! Lol my racing driver excuses are great hu!

 

I actually filled up around 1am at the Shell garage before the mapping day and she said your the first to have just filled up with it and explained the benefits. Then the next day you were posting about it.

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Oh really, eek! This will rub plenty of salt into you wound, but even my standard & tubby R32 has the edge on E46 330 petrols :D

 

Seriously though, if it was a late E46 330d & chipped (was there any black smoke?) they can summon a mighty ~250hp & ~400lbft from the depths of it's oily bowels to despatch pesky VWs with. You know and I know that centrifugal S/Cs don't do much below 4000rpm, so a beefed up 330D could easily catch you off guard in the wrong gear!

 

Bobbie's install was a little different to yours those though chap. Forged bottom end, Schimmel intercooler, schimmel short runner, schimmel BVH & Cams (IIRC) etc. You don't get any boost losses at all through those and the chargecooler is superb. The head and cams work well too.

 

The only thing I don't like about the Rotrex is stepped power delivery. It seems to jump from some boost, to all boost over a narrow powerband. I also didn't like having to run the MAF and filter 5" off the floor with S/Cs either, but each FI method has it's pros and cons as we know!

 

Your story is pretty much why I went turbo: to fatten up the torque curve and change the power / torque on demand. I spent 2 days with Vince mapping my Vortech stage 3 (12 psi - 321hp) back in 2006, only to get wasted by a rusty Nissan 200 SX!

 

I didn't realise you'd be cogitating for that long otherwise I'd have tried to sell you on turbos much sooner :lol:

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