Hey guys...you all provided great response to my tons of questions..so, what the heck - here's another...

As my search narrows - I've run across another 'vette: http://forums.corvetteforum.com/zerothread?id=499034

Mods:
Mongoose 415cid stroker mods:

6 liter cast iron block with a .060 bore
4” Lunati knife edge billet crank
Ross forged 11.8.1 Swain Tech coated pistons
6.125 billet rods
Crower cam with 217/ 226 .575/ .585 lift on a 114* lobe
TPIS racing heads with all the goodies
Katech high flow oil pump
Jessel 1.75 shaft-mount rocker arms
Zo6 intake manifold
SLP 85mm MAF sensor
Blackwing air filter
Ported throttle body
TPIS 1 3/4 long tube headers
Taylor thundervolt spark wires
Denso IT-22 spark plugs
B-cool HD radiator with 160* stat
Mongoose race exhaust
Custom pcm program
FLP level 4 transmission
Pro Torque 2900 stall converter
Hal 12 way adjustable shocks
Cryogenic slotted & dimpled rotors
Y2k rims powder coated black
Nitto tires

The price is VERY nice with ~12,000 miles on it! It's a '99 coupe/auto, sold by a forum member. It's by far the most inexpense modded vette i've found...and the owner has been great trading emails with me.

My question is ... does anyone have experience with these Mongoose packages or http://www.proautotech.com <-built the car. I don't think the car has any ET's or dyno sheets, however, with that package, built auto w/big stall pretty low ET's should follow? I'm guessing ~460rwhp? with nice torque?

I imagine a big benefit is the 6L iron block <-the motor has 11.8:1 compression, so a blower is out ;) - but should take a real nice shot of nitrous...anyway - as always, your feedback is appreciated!!

Thanks,
Jay

 

Interesting I knew http://www.corvetteconcepts.com had a Mongoose package. A topic recently discussed this shops work in a not so favorable light. I have not had any contact with either shop. Are these 2 shops related? I don't want to give Pro Auto Tech a bad name if it is not due. There was an MTI in Atlanta totally unrelated to the MTI we know in Texas. I have a Mongoose 400 bolt on pkg that was purchased used, but not sure who worked on the car. I have the previous owners name now and will have to call both shops.


[Modified by 93Polo, 4:30 PM 2/24/2003]

 

Don't if the 2 shops are related...hmm - I tried to call Pro Auto...but got no answer today...

 

They are two different shops. Corvette Concepts was like an installer or something. Ron owned Protech Auto. He was one of the original computer programers for the C5 and many many tuners used his service. I would say he knows what he's doing. He got divorced so that led to a down turn in his business.

 

I know the car and the car and that engine ROCK big time from what i have seen and read about it.

However, that is one baby **** cam for those big cubes and i do not think you will get the 460rwhp (thru your A4) without putting in a type of cam to take advantage of the big cubes. There are many stock bottom end 346 cid Ls1s out there running this same type of cam and many more stock cubed motors are running more aggressive cams than that.

I say buy the car and simply swap out cams. See MTI R1 cam on thier site, as that looks like the a great cam for this 425cid LQ4 Stroker.

MTI is finishing up my ironblock 427 LS1 this week for 98 A4 C5 and i will be running their most aggressive hyd cam, the S1, with specs of 244/244, .612 lift on a 112lsa. :yesnod: :cool: NEEDLESS TO SAY I'M PUMPED UP!

MTI 427 Roadster

 

Thanks man...good post - would you say that same cam you're going with would work well in this vette? I guess i'm just a bit confused, since i'm seeing some H/C C5s and Z06s putting down 460rwhp or so, esp the cartek X-package (i think) - yet, this motor is gonna do ~the same rwhp? I suppose the real key here is the rwTQ and ironblock?

So much to learn...so little time...

Thanks gusy!! :cheers:

 

Jay,

The basic package looks like a great set-up. All except the Cam. it is very small. If there is enough valve clearence and you can install a larger more aggresive cam, you should get close to 475RWHP through the A4.

The Torque converter is also a little mild depending on the rear. I would bump up the converter and make sure the rear is atleast a 3.73 or better with a hardened shaft.

Once these mods are all set up correctly, this should be a 10 sec car.

 

Thanks...I found these cams over at MTI:
X1 230 227 .591 .571 112
R1* 232 236 .575 .578 114
S1* 244 244 .612 .612 112

^Wow, only $400 too...geeeez...in the supra world we pay $600 EACH and we need 2 - ...heck, a bigger TC ~$700 and gears for $600, output shaft $400 - Looking at maybe $2100 <-The best part of the domestic world!! +labor of course...

Hmmm...a plan....

Jay

 

Depending on how well the heads flow on that 415cid cubic inch, the S1 cam that i am running may be a little too radical for that engine but not necessarily. I would talk to MTI (ask for Jayson and tell him i referred you) and talk to him about running the S1 cam. You can get the S1 cam from MTI on a 114 lsa also, and that may be just what the doctor ordered to really wake up your setup. Talk to Jayson (owner of MTI or Chris) as they are real pros and can custom grind a perfect cam for your setup also.
Also, don't get hung up on the peak rearwheel horsepower numbers on your motor either, as what really matters is the power the car makes under the peak numbers throughout the entire rpm band, as this is where the Stroker will really outshine a 346 h/c car making big power (like the Cartek X package, etc). The A4s pull considerably lower peak numbers on the dyno vs M6 cars or Z06s (M12 manual tranny) b/c of increased loss through the drivetrain on the A4s. I also will quote below a quote i saw from a gentleman called Nineball on this exact topic of peak rwhp numbers and he REALLY KNOWS HIS SH IT! I say you should buy this car as i think you can get a REAL SWEET deal on it not to mention its already set up with the best A4 tranny you can get for the extra power, that being the FLP Level IV. Here is the quote from NINEBALL i saw today on LS1.Tech.com, where alot of the HARDCORE PERFORMANCE MINDED LS1 GUYS hang out at (mostly f bodys bo vettes also:

"Don't compare peak rwhp values. If you overlay the hp curves of a stroker on top of a 346ci setup, the difference would be mega-obvious, especially in the torque department.

Why aren't the bigger engines making more power? Because we are all still using the restrictive LS6 intake. That intake only flows 280 cfm, and my heads flow 335 cfm. The bigger the engine, the more it is choked up by that intake. That is the primary reason.

My 434ci pulled 525 rwhp. That isn't bad considering it was thru a 12-bolt rear, 4.10 gears, 3.5" heavy-duty steel driveshaft, and on 28" drag slicks. In a stock driveline 6-speed, this engine would probably put down 540-550 rwhp. All that on 93 octane too."

Good luck and hope this helps.

MTI 427 Roadster


[Modified by MTI 427 Roadster, 9:38 PM 2/24/2003]


[Modified by MTI 427 Roadster, 12:40 PM 2/25/2003]

 

T76supra,
I know the car youre talking about!! He lives here in St. Louis. He is a great guy and knows his cars well. Ive seen the car many times, and it is
sweeeet!! It is one mean ride. Very , very fast. All black, tinted, looks very sinister. Anyway, good luck in getting the car- I dont think you would be disappointed.
Rob

 

Why dosent someone make a new intake?

EDIT INPUT: http://www.ls1tech.com/ubb/ultimateb...c;f=1;t=011241

in case anyone else wants to know there is no new intake because it wont clear the cowl. see the above link.....


[Modified by IwishIhadAvette, 3:09 AM 2/25/2003]

 

Call T.P.I.S in Chaska,Minnesota,they probably built the motor for Pro-Auto,Ron from Pro-Auto works very closely with T.P.I.S and most of the engines and heads and cams he installed came from T.P.I.S.

 

Rob -

Thanks for the info!! Yeah, a few local st louis folks have stepped up about this car! There's a number of good vettes out there, but the mods/price/miles..etc, of this car - Hmmm..very hard to beat!

Boweryboy - thanks for the tips...since you're local to S NJ - maybe I'll see you at the track some time.

MTI 427 Roadster - Very good posts...if I can work a deal on this car - I'll be looking to do the mods you and Boweryboy said...I'll phone MTI - however, East Coast Supercharging is only 30mi from me!

TEK WARRIOR - I'll give them a ring too...i noticed you run 10.70s at 130 (!!) on motor w/your 415" motor (wanna share you mods/tips??)

As for the restrictive LS6 intake...dang...there are NO aftermarket hoods that can clear a big intake?

Everyone thanks for the help here!! I just need a 10sec monster to beat up on all my old Supra buddies at the import vs domestic races!

Additionally, the owner cleared up that CorvetteConcepts does NOT have anything to to due w/ProAuto who did this car...additionally, the cam was done for emissions and bigger torque...ah, emissions...HAHAHAHA

 

I would like to point that with .06 over bore, your motor will not be very suitable for Forced Induction or big nitrous shot since the cylinder walls will be too thin for that. However, the motor will be fine running normally aspirated & with an iron block you won't have any sleeve issues to worry about.

Here are few ideas to increase this car's performance

-Bigger cam (I vote for MTI's X1 or R1. The S1 is too radical for daily driving). Also double check on the rocker ratio as I never heard about a 1.75 ratio on LS1. In order to determine the max valve lift you'll need to take into your account both the cam profile and the rocker arm ratio.

-Switch to a higher stall converter (4000 rpm stall max for daily driving). Go with a Yank converter.

-Switch to a higher ratio diff. I recommend 3.73, but this also depends on your converter choice.

-Cold air intake kit might add ~10 rwhp over what you have now.

-Bigger headers (LGM or Cartek 1 7/8"). This should net you another 10 rwhp or so.

Are you selling your Supra or just getting another toy?

 

T76,My car is a 6-speed with 4.10's.The 415 has LS-6 heads,hydraulic roller cam,don't know the exact specs but it's over 600 lift and 230+ duration.All my 10.70 runs were done in the warm weather 75+degrees,once the weather dropped below 50,I started snapping various parts of the driveline everytime I ran the car,the car has a 10.40 pass in it maybe later in the season,for now I'm setting the car up for nitrous.The car dynoed 523RWHP/508TQ SAE corrected through the mufflers.

 

Thanks for the info...very, very impressive! I just got off the phone with Chris over at East Coast Supercharging to discuss this car and the first changes to it - overall it's very hard to beat what's been done to this car already compared to the asking price! First changes: bigger cam, 3600 (at least) stall w/3.73 gears <-chris is testing this combo very soon and will then determine if it's the way to go, hard shaft, built rear-end.

Hopefully that should open up the motor and get me to some 10.70-10.80 N/A like yours...I'd like to get it to ~480-500rwhp N/A - with a big stall and auto, that should turn some real nice times!!

He also noted that it .06 overbore on the Ironblock is no problem when going to a blower :reddevil: