In reply to Stampie : That’s really an excellent question. I do know how cold the charge is on fuel injected sprint cars. They use pure alcohol and on some nights they come in with frost on the intake.
The question is will that negate the thermal gain from the compression of supercharging?
Alcohol will definitely drop the temps a lot, but if you can fit an intercooler, I'd still run one. It'll drop the temps a good bit before the alcohol does, so you'll still end up with colder intake temps (and more power potential / safety margin) than relying just on the alcohol for cooling.
In reply to rslifkin : when Grass Roots Magazine ran that article about air flow it started me thinking. If airflow drops at every bend and decreases by the length of the inlet tube maybe an intercooler has a cost of it’s own?
Be pretty simple to hook up to a flow bench to test. When you add that to the airflow decrease for length and bends. Is it possible that the use of alcohol to cool the charge instead of an intercooler would at least yield the same power?
If it does then there are three reasons not to use an intercooler.
1.
the thermal load on the radiator is reduced since air going through it isn’t preheated by an intercooler.
2.
Parts left off a car cannot fail.
3.
Parts left off a car do not add to the weight of the car.
I ve got to admit, I don’t know, I’m guessing here.
Maybe the magazine has the resources to test this?
Best way to achieve a track reliable Jag? Get in touch with JTR - Jags That Run. They'll sell you all the small block chevy parts you'll need to make this happen. Also consider that if you have a failure at the track you can source parts from any parts store and some roadsides anywhere in America.
If you must have a V12 Jag, don't track it. If you must track your Jag? V8 conversion is the easy button.
In reply to Xceler8x :
In the Jaguar world such things are called lumps. They are done by and for people who simply have no understanding or knowledge of how wonderful Jaguars are with their original engines.
Lumping a Jaguar with some crate motor or one out of a truck as compared to the original v12 means you will need to compromise on not just originality but power torque and durability.
Jaguar finished and won overall many races at LeMans 24 hour classic long before Chevrolet finally was able to get their Corvette to finish.
As to power? The V12 was making 750 horsepower on the watered down fuel the French use for the 24 hour race.
On the high octane we use here in America 850 horsepower is available. Not with some exotic limited availability special race only piece. But using mostly all factory parts.
NASCAR is the classic example. There is only one gasket in a “stock car” engine that is an actual production piece the rest are race only. So to call it a Chevrolet is foolish
Besides. Pushrods are things for little boys to play with.
An air/water intercooler might be less of a flow restriction than air/air. It would require less piping in most cases, as you don't have to get the air all the way up front and back.
frenchyd said:In reply to Xceler8x :
In the Jaguar world such things are called lumps. They are done by and for people who simply have no understanding or knowledge of how wonderful Jaguars are with their original engines.
Lumping a Jaguar with some crate motor or one out of a truck as compared to the original v12 means you will need to compromise on not just originality but power torque and durability.
Or by people who are bored with tinkering with the v12.
Xceler8x said:Best way to achieve a track reliable Jag? Get in touch with JTR - Jags That Run. They'll sell you all the small block chevy parts you'll need to make this happen. Also consider that if you have a failure at the track you can source parts from any parts store and some roadsides anywhere in America.
If you must have a V12 Jag, don't track it. If you must track your Jag? V8 conversion is the easy button.
You must've never read a FrenchyD thread, suggesting he lump his Jag. LMAO!
In reply to rslifkin :
Can you explain to me how a water to air works? Doesn’t it take the radiator water as it’s coolant source?
That’s at what, something up to 230 degrees? I know that people get concerned when the charge air from a supercharger or turbocharger gets over 200 degrees and start looking for a intercooler.
In reply to yupididit :
If you know what you are doing a V12 maintenance is a lot easier than the labor needed to do a decent lump job.
I know a lot of people get confused counting all the way up to 12 but Jaguar realizes that might be a challenge to some.
For those they mark it 1-6 side A and 1-6 side B.
See you don’t have to take your shoes off to count all the way to 12.
Plus they came out with a all aluminum 6 cylinder 4 valve per cylinder for those who get confused with side A & side B. Since it’s 1/2 the number of cylinders it’s lighter in weight but makes nearly the same power. More, much more if it’s supercharged.
If you absolutely have to have a V8 Jaguar makes one of those too. Only 4 liters all aluminum. And up to 550 horsepower.
frenchyd said:In reply to yupididit :
If you know what you are doing a V12 maintenance is a lot easier than the labor needed to do a decent lump job.
I know a lot of people get confused counting all the way up to 12 but Jaguar realizes that might be a challenge to some.
For those they mark it 1-6 side A and 1-6 side B.
See you don’t have to take your shoes off to count all the way to 12.
Plus they came out with a all aluminum 6 cylinder 4 valve per cylinder for those who get confused with side A & side B. Since it’s 1/2 the number of cylinders it’s lighter in weight but makes nearly the same power. More, much more if it’s supercharged.
If you absolutely have to have a V8 Jaguar makes one of those too. Only 4 liters all aluminum. And up to 550 horsepower.
I think you've typed this exact post (or close to it) a few times already 
In reply to Xceler8x : Don’t feel bad BMW and Mercedes Benz’s top engines are V12’s
As is Aston Martin, Maserati, and Ferrari
nice neighborhood to be in isn’t it?
No none of them are cheap or that easy. But putting a Chevy in them has been done to all of them.
In reply to yupididit :I’m sorry for my repetition. I understand those who Like Chevy. Heck I’ve owned probably a dozen in my lifetime. They’ve served me well and I’ve even raced them.
Expensive luxury cars depreciate so much in value so quickly that it’s easy to find those hidden gems to go racing with.
I prefer Jaguar over other makes because there are plenty of them and parts for Jaguar are a fraction of the cost of similar parts for other makes. Plus they are well served by the specialist industry.
frenchyd said:In reply to rslifkin :
Can you explain to me how a water to air works? Doesn’t it take the radiator water as it’s coolant source?
That’s at what, something up to 230 degrees? I know that people get concerned when the charge air from a supercharger or turbocharger gets over 200 degrees and start looking for a intercooler.
No you use a separate system. So a mini radiator, reservoir, pump, and air (booster intake air) to water heat exchanger. My understanding is it's good on the street because of the waters heat sink ability. Not sure how that would be affected by racing under constant boost.
Water / Air works fine under constant boost as long as the radiator is big enough and gets enough airflow.
In reply to Stampie :
Oh then it makes sense. Especially on the street or at Bonneville or in a boat.
I don’t think it would be the answer for my race car.
In reply to frenchyd :
What rslifkin says makes perfect sense and the plumbing space requirements are much lower.
Any suggestions on 2 "junkyard turbos" for a 4.8l ls? I was thinking about 2.3l Ford, but there may be better options to look at the pull-a-part for? Challenge car cheap. Thanks in advance. T
In reply to rslifkin :
So if you can keep the water temp down to say 180 degrees and your charge temp is 200 or more that 20 degree difference is enough to help?
Its been decades since I looked at air to air intercooler numbers. I vaguely remember something like a 50% drop in inlet to outlet temp was the goal?
Are you saying a 15% drop is more realistic?
Using coolant for air/water won't work well, the coolant is too hot. If you run a second water loop with an appropriate radiator for it, you can likely keep the water temps down around 100*.
FWIW, X308 XJRs use air/water intercoolers and I'm pretty sure they use a separate loop. The 03 / 04 Mustang Cobra also uses a separate water loop for its air/water intercooler. Looking at the setups on those cars might give some ideas of how it all goes together.
In reply to Gasoline :
Good question, one right in line with mine. I assume this is for road racing or street?
I’d think that slightly smaller is better for the street because it will spool up faster and still not make so much boost you blow head gaskets.
Gasoline said:Any suggestions on 2 "junkyard turbos" for a 4.8l ls? I was thinking about 2.3l Ford, but there may be better options to look at the pull-a-part for? Challenge car cheap. Thanks in advance. T
Holsets off of diesel Dodges.
Hx35 is typically what's found and suggested for junkyard LS builds, from what I've seen/read. Sloppy Mechanics usually buys Chinese turbos, though, so whatever floats your goat.
In reply to frenchyd :
Thinking purpose built Challenge car.
A big diesel single would be rare at the Atlanta Pull-a-Part & more costly from Craigslist. Half a 4.8 is 2.4 and twins might be easier to find and $$$ fit the budget.
frenchyd said:In reply to yupididit :I’m sorry for my repetition. I understand those who Like Chevy. Heck I’ve owned probably a dozen in my lifetime. They’ve served me well and I’ve even raced them.
Expensive luxury cars depreciate so much in value so quickly that it’s easy to find those hidden gems to go racing with.
I prefer Jaguar over other makes because there are plenty of them and parts for Jaguar are a fraction of the cost of similar parts for other makes. Plus they are well served by the specialist industry.
Hey I understand you. I just like to give you a little sarcasm about it. Seeing a XJS Race car with its v12 is always a cool sight.
frenchyd said:In reply to Xceler8x :
In the Jaguar world such things are called lumps. They are done by and for people who simply have no understanding or knowledge of how wonderful Jaguars are with their original engines.
Lumps? I had no idea. I was just thinking "If this guy wants to race reliably and inexpensively there's another way to skin this cat." Cat pun definitely intended.
Lumping a Jaguar with some crate motor or one out of a truck as compared to the original v12 means you will need to compromise on not just originality but power torque and durability.
Replacing a Jag V12 with a SBC means compromising on power, torque, and durability? When going from a Jag V12 to a small block chevy? Have you been talking to Bizarro Superman lately?
Jaguar finished and won overall many races at LeMans 24 hour classic long before Chevrolet finally was able to get their Corvette to finish.
If you had Jaguar factory support I'm sure this problem would be merely academic. Are you secretly a Jaguar factory driver and we don't know this?!
As to power? The V12 was making 750 horsepower on the watered down fuel the French use for the 24 hour race.
On the high octane we use here in America 850 horsepower is available. Not with some exotic limited availability special race only piece. But using mostly all factory parts.
NASCAR is the classic example. There is only one gasket in a “stock car” engine that is an actual production piece the rest are race only. So to call it a Chevrolet is foolish
Besides. Pushrods are things for little boys to play with.
Apples to oranges comparison here. We aren't talking about whether NASCAR is a viable racing series, the merits of pushrod engines, or providing proof of 850hp from a Jag motor. If you want to do some hot laps in your car with your stated goals I'm thinking turbo'ing your car is going to be an expensive, time-intensive, development program. If that's what you want then go and have fun! Some people think it's super fun to get kicked in the nuts so who am I to judge? Please keep us updated.
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