Question about twin turbo's

[Woodster]

Ok this isnt boat related but im hoping u guys can help me out..I have a new Sandcar on order and im trying to decide on an engine package..Ive narrowed it down to 2 choices.. One is a normally aspirated Chevy Ls1 with around 500Hp... Here are the specs
5.7 Ltr. 500 H.P.(pump gas)
V8, Aluminum Block, Aluminum Heads
480 ft. lbs. Torque
Custom Ported Cylinder Head
Retainers, Valves, Springs
A.S.A Race Camshaft
High Ratio Rockers
Double Roller Timing Chain With Billet
Gears
ARP Rod Bolts and Manley Push Rods
Corvette Intake Manifold
Or I can go with a twin turbo chevy..Its a 5.3L though
Aluminum Block Twin Turbo
625 Horsepower
645 Ft. Lbs. Torque
V8, Aluminum Block
Aluminum Heads
Plus:
Intercooler
A.R.P Head Bolts
ARP Rod Bolts
My question is, are Turbo engines reliable and can I expect a few good seasons out of it?? What about maintanence? Are there any issues I should know about? Anything u guys can think of would help me out alot. Ive never owned anything thats turboed so I dont really have any clue about it..Thanks for any help! :cool:

[Jordy]

Much like the boating world, the more power you throw at it, the more incidents you're going to have down the road. At 500 hp you should already be planning on a Mendeola tranny if you want it to last. They're pretty much the #6 drive of the sand world. I would think 500 hp would be a blast without having to worry about the turbos and all the accessories that go along with that system. Not to mention, with that extra 125 hp, it's more wear and tear on the rest of your drivetrain. If I were doing it, I'd go with the 500 hp N/A engine and be done with it. Blown up transmissions and CV joints aren't my idea of fun when you're out in the sand. Pretty much all the guys I go to the dunes with ditched their old turbo rotary monsters in favor of the very engine you're talking about. Now they can dune all weekend and just put gas in it. Before, there was always one or two cars down, even with the big Mendeolas and huge CV's.
Just my $.02 :D

[lucky]

i'd go with the natural - since your in the sand - turbos' get expensive

[cdog]

Not to mention to make that kind of HP in those engines you have a moderate amount of compression. Turbo engines need low compression. The turbos would be a waist on a 10.5.1 engine. You would more likely need 8-9. Or a big AC unit for the intercooler.

[Woodster]

Thanks for the replies..The car is getting a Mendeola S4 which is a sequential shift tranny..Another words its shifts like my dirtbike..Its rated to 900hp so im not to worried about that..Also getting 934 race cv's so im not really worried there either..I guess you guys are right though, the 500HP N/A would be pretty worry free..The turbo engine comes with a big ass inercooler as well..

[Woodster]

Anybody else have any input?? Heres a 3rd option I can go with as well..Are the Magna superchargers any good?? It has a built in inercooler as well
5.7 Ltr. 530 H.P.(pump gas)
V8, Aluminum Block, Aluminum Heads
575 ft. lbs. Torque
Plus
Magnacharger
Supercharger/intercooler
GM Hi-Performance Cam and Springs
Double Roller Timing Chain With Billet
Gears
ARP Rod Bolts, Head Bolts and
Heavy Duty Push Rods

[Mrs CP 19]

We have twin turbo in the boat. The engine was specifically built for the turbo set up. As mentioned...you need low compression, should be 7 or 8 to one. NO MORE. also, our cam is a turbo specific cam. Also, we will have our engine gone thru as preventive maintenance every winter at about $2500.00. It's an expensive set up and worth the extra maintenance. Don't forget about turbo lag...natural aspirated will give you more instant power. Good luck...Jill

[wsuwrhr]

The gearbox is the key, and yours no doubt the the Ferarri of the bunch. I think it shifts a little "clunky", but that is just the way it is. Very cool gearbox.
I have a custumer with that same gearbox with 572 bolted to it, and it works perfect, another has a Fortin of the same design with a torque converter and a NA LS1 bolted to it, it your exact combination of hardware, but I think he is running the truck manifold, the ASA cam sure makes that BadBoy lope. We installed the drivetrain in a Funco, and he headed off to Glamis Friday.
Depending on the weight of the car, NA 500hp would be plenty of power. Trust me, it wasn't long ago that a turbo'd VW with 300 hp was enough to get around the sand. Drive the car, get used to it, and if you want to go bigger, you can always sell the motor and step up the power.
Brian

[Unchained]

I hadn't heard of the Mendeola transaxle so I looked up the web site.
I guess things have changed some since I ran the dunes and sand drags.
I'm amazed that someone would pay over 10k for a transmission.
Judging from the picture it looks like a glorified VW trans.

[Woodster]

Ya actually your pretty right..I couldnt belive the trannies are that much either..But when your running this much HP and tourqe with a transaxle it dosent leave me much choice..Next best option would be a Fortin or Albins tranny..Those run around 14-16k. :( :(

[wsuwrhr]

I hadn't heard of the Mendeola transaxle so I looked up the web site.
I guess things have changed some since I ran the dunes and sand drags.
I'm amazed that someone would pay over 10k for a transmission.
Judging from the picture it looks like a glorified VW trans.
The sad part is the best 091 box just won't live with a turbo'd Subaru or anything else above 300hp. Splits the case across the differential.
You have to remember, that case was designed for 40-60 hp.
Mindy's are a little stronger, but they still have their weak points, since most of them still use VW internals. The newer, bigger(more expensive) ones use other ring and pinions.
Brian

[wsuwrhr]

Ya actually your pretty right..I couldnt belive the trannies are that much either..But when your running this much HP and tourqe with a transaxle it dosent leave me much choice..Next best option would be a Fortin or Albins tranny..Those run around 14-16k. :( :(
Fortin builds a nice part also. You get what you pay for.
Comparatively, I can't believe the price they get for outdrives, considering what is inside them, and that they STILL break.
Brian

[wsuwrhr]

Woodster,
I talked to Dan when he got back from Glamis, he said the car was bitchen. More than enough usable power.
He is an engine developer, so he is real picky about powerplants and driveability.
Brian

[Woodster]

Hey thanks for asking..My buddy has the 410 Hp Ls1 in his car..It actually has plenty of power..Im just gonna go with the 500HP N/A engine and maybe next year add a whipple on top.. :shift: Thanks again for the replies

[Unchained]

So the more things change the more they stay the same.
People are STILL thrashing the same VW trans that was made for 60 hp but now it has been bandaided to handle more hp and now people are hooking a V8 to it.
I remember guys swapping out their broken VW transmissions in the parking lot at the dunes.
That's why I ran a Honda car engine/transaxle.
I never broke a trans after hundreds of 8000 rpm holeshots.
Of course the whole buggy only weighed 850#
It took a dual diaphragm clutch to hold the engine with 27 lbs of turbo boost.
I did break a few axles though. They would expire after a year of HARD use.
You could see where the spline on the drive axles was actually twisting where it went into the hub.
I got my whole setup from a wreck for $ 150.
Even got a couple spares from other wrecks but never used them.

[bonesfab]

go natural to start with and learn the car then bolt on the magnusson kit, add 100 hp and 100 ftlbs of torque and enjoy. turbos are great but in the sand the low end from the magnusson is where its at. :cool:

[Woodster]

go natural to start with and learn the car then bolt on the magnusson kit, add 100 hp and 100 ftlbs of torque and enjoy. turbos are great but in the sand the low end from the magnusson is where its at. :cool:
THe 500HP N/A engine has 10.5/1 compression. Will I still be able to add a blower on to it later? I dont care if I have to run race fuel..Thanks :shift:

[wsuwrhr]

THe 500HP N/A engine has 10.5/1 compression. Will I still be able to add a blower on to it later? I dont care if I have to run race fuel..Thanks :shift:
10-1 is a time bomb for forced injection if you don't have your cookies straight. 7-8 is the number to suit you better.
Much cheaper to sell the motor when you are done with it and build another one. Stock LS-1's are becomming a dime a dozen anyway.
Brian

[Woodster]

10-1 is a time bomb for forced injection if you don't have your cookies straight. 7-8 is the number to suit you better.
Much cheaper to sell the motor when you are done with it and build another one. Stock LS-1's are becomming a dime a dozen anyway.
Brian
Thanks alot for your help..I ended up going with the 500HP N/A engine..It should be plenty in a 2000# sandcar. If not I was told by the Engine manufacter that i can add a blower to it later..Just run 5-6 PSI boost and do a cam change and ECM change..Thanks again :shift: