Turbocharged V8..good or bad idea? How much $$$$?
Discussion
Okay, maybe I am getting a little ahead of myself at this point. I haven't even ordered the first parts of the car, but I feel choosing an engine option is important to plan the whole project. I was thinking of getting the 6.3 litre 534 horsepower engine to start off with to get used to the car. Afterwards, I was thinking of upping the ante by turbocharging to get more horses out of the brute. Is this a good idea? What would be required? Would I have to get low compression parts and rebuild the whole engine all over again? 
If your compression isn't to high to start with you could use a low boost system, say 5psi and squirt water in, if you get any pinking. I doubt that in an Ultima you would use boost for very long, detached retina's spring to mind! A compression ratio of 9.5-10:1 would probably be the max you go to without decent engine management. 9:1 would be preferable for a low boost system IMHO.
You should also be very careful you don't ruin the driveabliity of the car. One of the great charateristics of the sbc in the Ultima is it's throttle responce from any revs and in any gear.
Maybe go the route Stig has if your not satisfied with 500+ bhp. A supercharger is much better at smoothing out the power supply.
IMHO only
Paul
Maybe go the route Stig has if your not satisfied with 500+ bhp. A supercharger is much better at smoothing out the power supply.
IMHO only
Paul
Ultimaanimal is a good one to speak to as I beleive this is what he is doing, also Kurt from the US has done a 1200bhp one!!!
Seeing as I am an rpm man, I love turbo's and I think a SBC with twin turbos would be increadable.
However I think you will find a 500+bhp normally aspired engine will blow your mind anyway. I personnely would spend the extra money on an alloy block and other expensive weight saving things.
Seeing as I am an rpm man, I love turbo's and I think a SBC with twin turbos would be increadable.
However I think you will find a 500+bhp normally aspired engine will blow your mind anyway. I personnely would spend the extra money on an alloy block and other expensive weight saving things.
Kurt tells me with his 1200hp dialed down to 650, it's nearly impossible to get traction with street tires. He's topped 225 mph with one more gear and a bunch of throttle to go. He had a few scary moments on the bumpy roads and has since parked the car. Build a milder engine that you can control and get traction.
450 rear wheel hp will be good for 140mph+ in the 1/4 mile. Ultimas are so light you don't need tons of power. My $02.
450 rear wheel hp will be good for 140mph+ in the 1/4 mile. Ultimas are so light you don't need tons of power. My $02.
Getting back to the original question. When you build the engine initially, you should build a turbo engine (ie low compression and using internals rated for the sort of power you'll expect from the final engine) and just not fit the turbo's until you're ready. Then it will just be a case of getting the torbo's, plumbing them in, and setting it all up (just! Hah!).
I'm not sure how easy it would be to get the sort of power you're talking about from an unturbocharged turbo engine though. I would have thought that you would be better off saving your pennies up front and buying the engine you want (with turbo's), or just sticking to the (more than adequate) normally aspirated route.
To go for a regular normally aspirated engine, and then put any sort of worthwhile turbo on it would require enough engine work to make it impractical, or at least costly (unless you go for the light pressure turbo option, which isn't really going to give you enough of a power hike to justify the cost of the plumbing).
James
I'm not sure how easy it would be to get the sort of power you're talking about from an unturbocharged turbo engine though. I would have thought that you would be better off saving your pennies up front and buying the engine you want (with turbo's), or just sticking to the (more than adequate) normally aspirated route.
To go for a regular normally aspirated engine, and then put any sort of worthwhile turbo on it would require enough engine work to make it impractical, or at least costly (unless you go for the light pressure turbo option, which isn't really going to give you enough of a power hike to justify the cost of the plumbing).
James
Initially the idea of a turboed engine is great. I would do an engine no larger than 5 litres (smaller if possible for desired hp and low end trq.) and aim for 550 hp. I like the idea of a turbo in hopes it would save weight by using a much smaller engine. Problem is there are no Chevy SB turbo kits. Kurt D. did an amazing job engineering his car but I think it is a significant task that costs alot of $$ and time.
I think it will be very challenging and be a little ??? for reliablilty. Get a blower, or an aluminum block and a fancy EFI system.
Good Luck, good question (I've been afraid to ask)
I think it will be very challenging and be a little ??? for reliablilty. Get a blower, or an aluminum block and a fancy EFI system.
Good Luck, good question (I've been afraid to ask)
I may be wrong but the Ultima does not suit a turbo. You have a light car that handles well with linear power. A low compression turbo may well work but anything with moderate boost would destroy the balance of the car. Just imagine start of a bend 2,500 rpm (no boost) and 250bhp, mid bend 3,000 rpm (boost kicks in) and 400bhp and bend exit 3500 rpm 600bhp. I feel that a tuckshop moment would happen.
If you want forced induction use a supercharger.
If you want forced induction use a supercharger.
We are getting in the Supercharger/Turbocharger bedate.
I don't know a lot about superchargers but my understanding of them (gleamed not from experiance I must add) is that they tend to tail away earlier than a turbo, which would probably suit the big V8 (and an Ultima as Blue said).
However without knowledge of what the guys who have gone the turbo route have done, I have my doubts about the suitability of turbos in an Ultima.
The major problem my cossie has is getting rid of the heat. This is not just vital in producing the power, but is a major factor in keeping the engine together. Large radiators and huge intercoolers are the norm and thats just for one turbo with all that airflow around the engine.
Not sure how you could replicate this in the Ultima, but I know Animal knows quite a bit about this and am interested to see what he comes up with.
With such a variety of engine configurations happening at the moment....Superchargers.... Twin Turbo's.... V12's....Jag V8's....I can't wait to see them all in action.
It'll be mad.....
I don't know a lot about superchargers but my understanding of them (gleamed not from experiance I must add) is that they tend to tail away earlier than a turbo, which would probably suit the big V8 (and an Ultima as Blue said).
However without knowledge of what the guys who have gone the turbo route have done, I have my doubts about the suitability of turbos in an Ultima.
The major problem my cossie has is getting rid of the heat. This is not just vital in producing the power, but is a major factor in keeping the engine together. Large radiators and huge intercoolers are the norm and thats just for one turbo with all that airflow around the engine.
Not sure how you could replicate this in the Ultima, but I know Animal knows quite a bit about this and am interested to see what he comes up with.
With such a variety of engine configurations happening at the moment....Superchargers.... Twin Turbo's.... V12's....Jag V8's....I can't wait to see them all in action.
It'll be mad.....
If you want to run a turbo motor then build and dyno it with the turbos on from the word go. Putting turbos on whilst the engine is in the car will be a total nightmare. You need to get the engine mapped properly on the dyno. I know this from experience and the alternative is not pretty.
To do the job properly won't be cheap though as you will want to run a decent management system and they are expensive.
Don't let this put you off though. Turbo engines are fantastic and don't let anyone tell you otherwise.
To do the job properly won't be cheap though as you will want to run a decent management system and they are expensive.
Don't let this put you off though. Turbo engines are fantastic and don't let anyone tell you otherwise.
LOL Paul....everyone has an oppinion.
To be fair, there is a lot of truth in what most people have said, but alas there is the search for the Ultimate Ultima..LOL.
As the question is directed at (has anyone done or thought about this) yes i have and am right in the middle of building such an engine from scratch. I have learnt alot so far from the engine designers at work and am constantly pestering them for info. The areas of concern when fitting this engine to an Ultima is one of Heat and packaging...it is a BIOTCH to package a twin turbo set up. So far i have looked at 3 different ways to package the turbos and have decided on a route forward and currently the plan is to use the original factory headers and hack the design to suit the Turbo's (mine are 2 X T5 Garrett jobies) I managed to pick up a real dirt cheap dry sump kit at the Autosport show...KEWWWWLLLL
from the guys at ARE in the US of A.
If you are after specifics of engine internals then this is what i would advise...and its only advice
Heads...get the right ones for you engine, most of the power is delivered by good head design...i bought the AFR 1105 CNC competition heads.
Compression ratio needs to be no higher than 9:1 exceed that at your peril in a car for road use, i ended up going for 8.5:1 with a little higher RPM
DO NOT EXCEED 390 Ci, the engine will destroy itself unless you get a highly modified block (some are more robust than others....talk to GrumpyVette at ChevyTalk website, he can give you casting numbers which are heavier built than standard and will take more distortion. My engine is standard 350Ci (dont need anymore and it will rev better than a 383)
Pistons and rods, if you can afford them, use the 6" rods and higher mounted pinned pistons this will give you a better rotating mass and ballance and much quicker throttle response....i ended up getting a Lunati crank as well
Ignition system and fuel system is courtesy of Motec M48Pro and using a 34-1 timing plate (no distributor) and wasted spark individual coils, this will stop the blowing out of the spark at high boost (common problem on early CART motors i worked on)
Fuel mapping is done via laptop on the Dyno (when completed) and fine tuned when driving on the road...just a case of hitting the enter button on the laptop
DRY SUMP THE MOFO....or you will kill the engine, turbo engines run a lot hotter than NA engines so a good oil cooler is also required.
Intake manifolds and injection fuel rails are courtesy of Kinsler with twin TP sensors.
Ermm...i think thats it for the time being.
On the subject of drivability....hmmmm, The main difference is certainly going to be the immediate grunt you get from a Supercharged engine compared to the mild power then RUSH from a twin turbo, which is gonna be a bit of a problem in the Ultima. A well built 350ci with the right bits and well matched will stand 20+ PSI of boost (if you remove every brain cell in your possesion)...i am working on 8 to 10 PSI for road use and 22 for track only....expected power output of a 8 to 10 PSI is about 600 BHP and a little milder Torque (same as Stigs engine or very close but with about 10% less torque) but with the added advantage of no weight up on top of that lump and much lighter as a unit per-se. However, wind up that boost and errrrmmmm well, i leave it to your own imagination. but expect to be given new underwear...im gonna equip myself with stainless steel skiddies.
To be fair, there is a lot of truth in what most people have said, but alas there is the search for the Ultimate Ultima..LOL.
As the question is directed at (has anyone done or thought about this) yes i have and am right in the middle of building such an engine from scratch. I have learnt alot so far from the engine designers at work and am constantly pestering them for info. The areas of concern when fitting this engine to an Ultima is one of Heat and packaging...it is a BIOTCH to package a twin turbo set up. So far i have looked at 3 different ways to package the turbos and have decided on a route forward and currently the plan is to use the original factory headers and hack the design to suit the Turbo's (mine are 2 X T5 Garrett jobies) I managed to pick up a real dirt cheap dry sump kit at the Autosport show...KEWWWWLLLL
from the guys at ARE in the US of A. If you are after specifics of engine internals then this is what i would advise...and its only advice
Heads...get the right ones for you engine, most of the power is delivered by good head design...i bought the AFR 1105 CNC competition heads.
Compression ratio needs to be no higher than 9:1 exceed that at your peril in a car for road use, i ended up going for 8.5:1 with a little higher RPM
DO NOT EXCEED 390 Ci, the engine will destroy itself unless you get a highly modified block (some are more robust than others....talk to GrumpyVette at ChevyTalk website, he can give you casting numbers which are heavier built than standard and will take more distortion. My engine is standard 350Ci (dont need anymore and it will rev better than a 383)
Pistons and rods, if you can afford them, use the 6" rods and higher mounted pinned pistons this will give you a better rotating mass and ballance and much quicker throttle response....i ended up getting a Lunati crank as well
Ignition system and fuel system is courtesy of Motec M48Pro and using a 34-1 timing plate (no distributor) and wasted spark individual coils, this will stop the blowing out of the spark at high boost (common problem on early CART motors i worked on)
Fuel mapping is done via laptop on the Dyno (when completed) and fine tuned when driving on the road...just a case of hitting the enter button on the laptop
DRY SUMP THE MOFO....or you will kill the engine, turbo engines run a lot hotter than NA engines so a good oil cooler is also required.
Intake manifolds and injection fuel rails are courtesy of Kinsler with twin TP sensors.
Ermm...i think thats it for the time being.
On the subject of drivability....hmmmm, The main difference is certainly going to be the immediate grunt you get from a Supercharged engine compared to the mild power then RUSH from a twin turbo, which is gonna be a bit of a problem in the Ultima. A well built 350ci with the right bits and well matched will stand 20+ PSI of boost (if you remove every brain cell in your possesion)...i am working on 8 to 10 PSI for road use and 22 for track only....expected power output of a 8 to 10 PSI is about 600 BHP and a little milder Torque (same as Stigs engine or very close but with about 10% less torque) but with the added advantage of no weight up on top of that lump and much lighter as a unit per-se. However, wind up that boost and errrrmmmm well, i leave it to your own imagination.
but expect to be given new underwear...im gonna equip myself with stainless steel skiddies. Wow, looks like I created a MONSTER TOPIC!! LOL 
Thanks for all the info! Anyway, given the advice from all you guys, now I am not sure which route to take. I already know the Ultima GTR is a very light car, and a turbo wouldn't really be needed for it to go extremely fast. I love turbo engines, I think they are very cool! But, I also love the GRUNT of the 6.3 litre engine that comes equipped in the Tiff Needell video. Now, if I can get the cool grunt with the awesome turbo spool whine without crapping my pants when I push the magic pedal, I will be fine..LOL! How fast does a NA Ultima feel anyway? I know it is fast as hell, but how fast does it feel?
>> Edited by ULTIMALOVER on Tuesday 21st January 07:42
Thanks for all the info! Anyway, given the advice from all you guys, now I am not sure which route to take. I already know the Ultima GTR is a very light car, and a turbo wouldn't really be needed for it to go extremely fast. I love turbo engines, I think they are very cool! But, I also love the GRUNT of the 6.3 litre engine that comes equipped in the Tiff Needell video. Now, if I can get the cool grunt with the awesome turbo spool whine without crapping my pants when I push the magic pedal, I will be fine..LOL! How fast does a NA Ultima feel anyway? I know it is fast as hell, but how fast does it feel?
>> Edited by ULTIMALOVER on Tuesday 21st January 07:42
I ran across an item that someone here may find of interest. Good potential for NA power.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33613&item=2400694091&rd=1
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33613&item=2400694091&rd=1
ultimapaul said: Andy, check out Ultimalovers profile! Just popping to the VW meet may not be a viable option
Ultimaandy, I would love to come and take a drive with you. Only thing is, I would have to take a huge trip across the Atlantic to get there, I live in the US. But, thanks for the offer!
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