Turbocharging a VT V6 Auto

[KamikazeR33]

i dont think he wants to do anything now except put a s/c on and thats all

lazy bastard... no one wants to have fun these days

[Roy]

lol... i think he may even consider selling the car and catching the train

[Steve]

there are alot of assumptions there - and you know what they say about assumption. I agree, horses for courses.

Who assumes GM engineers are idiots? You are the first person to imply it directly or indrectly.

If pushrods are such a wonderful thing, why arent they being used more? Wouldnt everyone be using them. GM and Lotus built a 5.7L 405hp (close to 300kw) DOCH engine - and how much did that cost compared to say a small block chev at the time? Or even today?

I do believe economics comes into the equasion - just like the reason I have been told (yes it is hearsay, but it until I uncover evidence otherwise, I'm sticking with it) that GM replace the RB30 with a buick V6 predominately because it is so much cheaper to produce/source. Would it not be reasonable to believe that this could be the case with V8 engines too?

Another thing you have to consider is that in society stigmas get attached to certain things. A guy a work told me once that he would prefer to own any v8 than any other engine. Australia has followed the US with a stigma of big is best - why do you think ford reintroduced the V8 - consumer demand. Consumers werent demanding more powerful 6 cylinders, no, they wanted v8s - end of story - the tradition of big V8s and cheap petrol still lives on.

And as you say Roy, horses for courses.

But they are still dinosaurs.

How can you compare an engine that has millions of R&D thrown into it, produces more power with less cubes and say 'but no, my unaltered design, gas guzzling pushrod isnt a dinosaur'

Xeron, you are trying to tell me that the OHC engines of 20 years ago is still alive and well today, just to be picky, they have changed a bit since then. Let me explain a bit further.

I still remeber pulling down my first V8 back in 1985 - it was a 302 windsor out of an XY (1971) sedan. this is probably before some people reading this forum were born. And ford still put them in mustangs only a couple of years ago. Sure they had been 'developed' but basically the same design.

Can you give me one example of a 20 year old twin overhead cam 6 cylinder engine that is basically the same design as say, and RB25?

Originally posted by Roy

As for pushrod engines being dinosaurs, well i think it horses for courses.

GM/Chevrolet built in conjunction with Lotus a quad cam 32 valve 350 Chev.  It had 405hp and was a sweet engine. Limited run option called ZR-1 from 89-95 (may have been '94)

Whilst building these engines, they were using under 5L quad cam V8s in luxury cars etc, so know how to build a quad cam multi valve engine.

So do yourself a favour and read up on the history of the GenIII engine and see why they stuck with pushrods for their premier performance engine. Dont assume GM engineers are idiots.

You will be surprised how pushrods, whilst not being ideal from some design perspectives, are perfectly sound for a fistful of revs, allow more compact packaging (see how wide quad cam V6/8s are), cost of manufacture, reliability ... the list goes on.

And before you all assinate the reliability side of things, US GenIIIs dont have the piston slap problem, and i dont hink you can relate this Aus problem to the fact the engine uses pushrods.

Go back to the mid 90s and the Indycar series. Mercedes Ilmor actually built a pushrod engine for the class, as by the rules it allowed them to run more boost. If i recall correctly the rules were soon changed.

[Xeron]

"How can you compare an engine that has millions of R&D thrown into it, produces more power with less cubes and say 'but no, my unaltered design, gas guzzling pushrod isnt a dinosaur' "

Trust me, just as much has been spent on pushrod engine development, plus alot of them have many decades R&D behind em, it helps. And then check out the fuel economy of say an ls1 commodore, and compare it to a skyline. Shit those old pushrod dinosaurs dont do too bad! Specially since they have more power stock for stock.

You just seem to be of the frame of mind 'oh it aint the latest thing on the market, it must suck'

[Roy]

Where did that come from?

i can hear the kids in the playground... "fight, fight, fight"

Steve... im not having a stab, and not looking for a fight. I cant fight and you'd smash me!

I read back over my post and and can see how " do yourself a favour", "Dont assume GM engineers are idiots." can read a little arrogant/condescending. Wasnt my intention

How about instead of do yourslef a favour ... it read, see if you can find an article on the GenIII when it was introduced. I had a Car Craft laying around somewhere. Its an interesting read to see why they chose pushrods.

As for GM engineers being idiots, well there does seem to be a belief that they cant build or design a decent engine. I was just trying to say that there was sound design and performance reasons why they chose not to step out of the dark ages. Its not because they cant, or are stupid/incompetent, they chose not to. So i threw in the word idiot not expecting anyone to take offence?

Im not saying pushrods are a wonderful thing, am I, did I? If i had it my way, every Commodore would be getting around with an LT5 Chev (ZR1 engine)

why would you go and put in a dinosaur engine that burns huge amounts of oil, has crappy fuel economy, and doesnt generate huge hp

Your obviously not a fan of their product, The scary thing is im guessing that more money has gone into the Gen III?

GM replace the RB30 with a buick V6 predominately because it is so much cheaper to produce/source. Would it not be reasonable to believe that this could be the case with V8 engines too?

Probably, but the Buick V6 did have more power and low down torque . Shame its as rough as guts and shakes itself to pieces.

How can you compare an engine that has millions of R&D thrown into it, produces more power with less cubes and say 'but no, my unaltered design, gas guzzling pushrod isnt a dinosaur'

I dont know... um maybe dinosaurs are extinct and pushrod V8s still roam the streets? If we are talking RB25DET to GenIII, it doesnt produce more power, does it, 225kw or something vs 185kw

Note: Nothing in the above is intended to be antagonistic, just in case i have put my foot in it again:rolleyes:

[Steve]

Not that frame of mind at all, but please do give an example. You say pushrods have many decades of R&D behind them, but yet you also say a DOHC engine is older than a pushrod - so your point is totally mute.

the latest thing on the market - dude, do you acutally know when the RB26 was first put on the street - certainly caused a few eyebrows to be raised at mount panorama in the early 90's - over a decade ago.

Perhaps you are of the mind 'oh its been around for so many years it must be good'

I dont believe that pushrods are all bad, just that they are behind the times - just because you were brought up on it and told pushrods are the shit doesnt make it true - all I am saying is look at what is around and get over the whole 'cubes and pushrods' it really is so passe. this sort of attitude kept cars off the street back during the turn of the century - dont be a technophobe, embrace technology and try and do things smarter.

Same sort of thing with fuel injection and carbies - so many people scared of them - keep saying that you could get a 10 second car with a carby - yes, all true, but that doesnt mean its the best way to do things does it?

Bottom line is that this thread was about what to do with a V6, and while it is possible to turn it into a fire breathing beast at what cost. Do you really think it would be easier to put an RB30DET in and produce 300+ kw at the treads, or try and get the stock V6 (90rwkw) performance up to that level? Even the RB30E stock made better power than that - 16 years ago.

[Roy]

Either buy a CAPA kit, or sell it and buy the last of the 304 VT Commodores. They are cheaper then the Chev engined Commodores and there is nothing unknown about these engines.

Personally I dont see the point of putting a Nissan 6 in a Post VL commodore. It would be great, but i dont think its worth the expese when you can get Commodore with a Supercharged 6/304/350.

If the car came out with an engine that is a good basis, then i think you should use it. If your after turbo performance, i dont think you should be behind the wheel of a post VL Commodore.

Hey Steve what power did RB30E have in the R31/VL. Wasnt it something like 117kws???

Another alternative is that there is a class of sprint car that uses the Holden V6, just like the Formula Holdens do. An old issue of Zoom (Julian Edgar era) detailed one of these builds and they had a good amount of grunt for reasonable coin.

[Steve]

I wouldnt hurt anyone in a fight, as I just dont beleive in it - so were both safe there:D

As for comparing power figures of the engines, spose my 'produces less power' comment was not explained very well. Put an exhaust and EBC on an RB25 (or even better RB26) and see what happens - they have been strangled from the factory due to power agreements. Well the RB26 was, but you couldnt have a single turbo produce more than the twin godzilla engine now could you?

I am really not sure about more power from a Buick engine to RB30E - seen them pull well over 100rwkw (RB30E) on dynos, more than once, in what I believe (dont know for sure, anybody got the acutal figures) was stock form.

Sorry if you took my posts as any sort of attempt at antagonism, just getting into the debate/discussion

Do you have any links to info GENIII engines that is similar to in your car craft mag, I would be interested to have a look.

Cheers

[Roy]

RB30E - 118kw @ 5200rpm , 247Nm @ 3600rpm.

Sure your not thinking of

RB30ET - 150kw @ 5600rpm , 296Nm @ 3200rpm

And again im not saying GenIIIs rule, but the Holden tuning on them is pretty ordinary. Apparently remapping the ECU with exhaust can reap a lot of power.

An old Zoom had a comparo, with the GenIII having exhaust and airflow meter, vs RB25 with exhaust, boost, intercooler both having 190-200rwkws.

If you read the latest HPI and read about the grunt the Corvette displayed which uses a very similar spec engine. (cam and ECU are about the only changes)

Ill have a look for the article on the GenIII.

Is it obvious my loyalties are with whatever gets me down the road at a rapid rate of knots. I love the RBs and turbos, but i wouldnt scoff at a Z-06 Corvette, TVR, or a 65 Fastback Mustang, 68 RS Camaro... the list goes on.

[KamikazeR33]

zaust and tuning - bout 50kws extra

[Sydneykid]

Speaking of pushrod classics, saw a Shelby GT500 Mustang at Miranda today... Very Dark Blue, slightly metallic.... she was beautiful.. and the sound..... magical.... even at idle... i turned the stereo off just to listen to it for 2 minutes...

[Xeron]

next year i think it is the base model corvette is gonna have 450hp, not bad for that old bunky pushrod heap of crap aye. Although i guess its a bit below the dodge viper, another bunky pushrod piece of shit that should get with the times and go dohc, riiight?

And yes, DOHC is older technology, my reference was to the fact the buick 3800 itself is alot older in design, infact it dates back to originally being a v8 engine. I think it goes back to the 60's, not too sure off the top of my head sorry.

And back to the original topic. Yes i believe it would be easier to get a s/c buick 3800 block, have it internally balanced and run forgie pistons, strap a big ****ing s/c on it and get 300kw at the treads that it would be to do a cross manufacturer engine and transmission swap.

Sorry i just get worked up when people who really dont know anything about an engine automaticly assume its a piece of shit. Not only have buick 3800's run in the 7's down the 1/4 (i think a few have done 6's, but yer whatever), not only are they used in many racing series around the globe, but they come stock in the commodore too. Just cause u dont see aussies doing anything with em dosn't mean there crap people.

edit: and just for the record, i wasn't brought up around pushrods, i dont really care either way, i just wish people would look at an engines facts, not just there own opinions which are biased as all hell.

[Cubes]

Just a quick rough Engine Comparison

121kw - 304 V8 Holden (VL VK Etc)

165kw - 304 V8 Holden EFI (VN VS etc)

185KW - 304 V8 Holden EFI SS Motor

114kw - RB30E (Single Cam 2 Valves Per cylinder)

121kw - 3.8ltr VN V6

157kw - 4.0ltr Ford (Single Cam 2 Valves Per cylinder)

171kw - 4.0ltr Ford XR Motor

147kw - RB25DE (Twin Cam 4 Valves Per Cylinder)

180kw - New 4.0ltr Ford (Twin Cam 4 Valves Per Cylinder)

Why would the US be spending more $$ on R&D compared to the Japs? Its not really good enough to say I think as that is simply speculation. Just a couple of arguments against....

Don't the Japs have a larger population?

Don't the Japs have a larger turnover of cars? (Due to their Sell before it becomes a Dinosaur policy)

Although the 3.8litres were good and went well due to good matching of gear ratios (I hope FORD are listening) they become tired very easily and need rebuilds quite often when hammered. The Taxi Industry is a prime classic example of the amount of rebuilds the 3.8ltr (Especially the early ones) needed. On average, they had reliability issues as soon as 200,000kays were clocked over. On Average remember I said.

The 5.7litre GenIII is an excellent motor and does produce good power but all I can say is "Have you driven a Ford Lately?"

If you haven’t or wont remove your self from the typical Australian/American loyalty to your favourite 'brand', look and feel the refinement out side the square box

Dribbled on a bit there didn't I :shake:

[Guest INASNT]

the age old battle between push rods and DOHC!

pushrods may be good but americans seem to just build cars that can only go in a straight line, maybe they should spend more of their apparent R&D time on making a car corner as well as just have straight line speed!

[Steve]

No not thinking of ET, cos the ones I have seen on dynos were skylines, not vl. Perhaps they had been chipped, cos they ranged from low 120rwkw to mid 130 rwkw. Underbonnet and exhaust seemed stock -wish I had asked a few more questions at the time!

Roy, I do believe variety is the spice of life, and there is a place on the roads from everything from mightyboys (always make me chuckle) and mokes (good fun to drive) to Camaros, Cadilacs, mustangs, thunderbirds etc. All good, depends on what you want to do.

I have read about the corvette in HPI, and yes the engine sounds quite nice, but to me using so much more cubic displacement to increase performance just isnt my thing.

I look at it like comparing a fingerpainting to a work of art. Both can produce the same result (an image), just one uses alot more finness.

[Xeron]

If the fingerpainting sold for twice the price tho, i'd much rather be the finger painter.

[Sydneykid]

Lets throw another engine into the mix

Honda K20series - in S2000 form (and Japanese Integra Type R form) produces 176KW for a 2litre 4cylinder... Meets worldwide emissions standards, with 7.8lt/100km fuel consuption on the highway or 10.5 in the city.

Now that is an engine that is HALF the size of a Holden 308 V8, which produces only 9KW more.... And that is a scary thought... imagine whats gonna happen when honda build a production performance V8..... they build a V8 for IRL, but not sure of the specs...although it has to be 4litres in displacement....

Obviously the honda holds the record for most horsepower per litre for a normally aspirated engine....

S of S

[Cubes]

My old NA stock VL 3ltr Made 90rwkw.. Stock exhaust, airbox.

Funny thing is when I had the 2.5" exhaust fitted they fitted crappy resonators and mufflers that had protruding little bits instead of flat holes in the muffler.. Power then dropped to 88rwkw.

88rwkw was the same power that a mate of mines RX7 with a Series 4 13B extendport with an exhaust and microtech made.

The 13B was origionally a turbo however this was bypassed So it could have made more if the 13B wasn't decompressed for the turbo.. I think.. Not sure that is what he told me anyhow.

Don't know much about the differences with the motors (turbo and NA) when it comes to Rotary's.

[Roy]

Yeh the Honda engine is awesome, great power and torque, for a 2L. Despite its revy nature it still has more torque throughout the rev range then say an MX5.

but to me using so much more cubic displacement to increase performance just isnt my thing

But 208Nm @7500rpm only gets you so far (Honda S2000)

Without resorting to the cost, heat and complexity of forced induction, what do you do? You can use an all alloy truck engine for 460Nm @4400rpm.

Plus i cant see any car manufacturer making medium-large 4 door sedan that is light enough to still offer credible performance with only 208Nm. Even the NSX engine only makes 298Nm @5300rpm, vs the 3.8l V6 Commodore engine in the VX which has 305Nm @3600rpm

I cant stand how Honda's biggest car engine is a 3.2L V6. Come on guys where is the 4.5L V8 in a swoopy 2door 4 seater???

[Xeron]

the s2000 engine has reliability problems tho. Theres already service bulletins out about it having oil use problems due to the piston design. In order to allow the super high rpms and good power, they pretty much eliminated the piston skirt, which puts massive strain on the rings, thus they wear faster, thus people are having excessive oil consumption.

Theres always a drawback