350 cu in LT5

[BennieC.]

What the highest horsepower can we get out of it. No force induction or NOS. Just naturally aspirated. The plenum and IH has been ported(siamesed). I'm in a process of installing SW headers and eliminating the Secondaries. I will change the injectors as well since car has 98k + miles on the clock. I will also install 4.09 gears. I'm also debating if I should just install the 385 cu.in. Lingenfelter built. Dynoed at 572 at the crank.

[XfireZ51]

Let's say Mr. Polatsidis is north of 560 crank using a .85 factor.

[Kevin]

mid 400's at the tires

[Schrade]

Good question... (http://www.zr1.net/forum/showthread.php?t=22543)

[BennieC.]

Let's say Mr. Polatsidis is north of 560 crank using a .85 factor.

What mods was done to it? Is it streetable?

mid 400's at the tires

And what was done to this also? Inquiring mind wants to know.:cheers:

[Paul Workman]

I hope Pete chimes in, but IIRC Pete posted 474 rwhp before his last go-round of cam grinds. His signature has links to one of his 11.4x second quarter mile runs* at Great Lakes dragstrip; a performance level I've seen repeated several times at the Crown Point Corvette Club's annual Corvette Shootout (next one coming up in a week (9/28/14), as a matter of fact!) But, that was before he upped his cam profile a couple years ago.

*Since then Pete has come to within 0.04 seconds of breaking into the 10s with his latest round of mods to his street driven, NA, stock bottom 5.7 LT5.

Any more details, Pete will have to provide (as the FBI gang is sworn to secrecy on pain of a Greek death what goes on in Pete's garage! [-X )

[Paul Workman]

Ya posted this as I was typing...

What mods was done to it? Is it streetable?

I drove his car once - even got to hammer it on a tuning run while he monitored his laptop. It is very streetable! Idle is about 850 rpm with a mild chop, and it has manners in traffic like a stocker. A real sleeper, especially with the NPP valves.

I'll let Pete or Marc fill in porting specifications for the "500" package if one of them wants to. But, it is safe to say the top end is aggressively ported, long tube headers with 3" outlets into 3" exhausts and B&B mufflers (now fitted with NPP valves to minimize drone), It is cammed, and the phasing is optimized for best performance while remaining streetable.

[XfireZ51]

Pete's ZR traps at 129+. It's also a bit lighter than the stock ZR w deletion of A/C for example. He's a good driver too.

[Pete]

I think if a LS motor can crank 500 rwhp from 350ci, I don't see why we couldn't get that from the 350ci LT5.

I think with some more compression among other things could be done but this will basicly be a race motor need to run hi octane/race gas and be loud.

Most want a nice quiet driver.
Pete

[XfireZ51]

I think if a LS motor can crank 500 rwhp from 350ci, I don't see why we couldn't get that from the 350ci LT5.

I think with some more compression among other things could be done but this will basicly be a race motor need to run hi octane/race gas and be loud.

Most want a nice quiet driver.
Pete

Pete,

For me, the possibility of owning a 5.7L motor that is putting down upwards of 550chp and yet idle at 850-900rpm without sounding like a bathtub draining was what attracted me. Aesthetically, its a great looking motor and one that isn"t seen very often.

[LGAFF]

Intake, Intake, Intake:cheers: is the key!

[FU]

Intake, Intake, Intake:cheers: is the key!

:handshak:

[BennieC.]

Intake, Intake, Intake:cheers: is the key!

Ok, tell me more about this magical intake. Are you taking about stock intake ported out or custom made sheet metal intake? Mine are already ported, siamesed as well. The plenum has been siamesed and the IH are siamesed and 1" down from the opening. I will open it up a bit more this week. I'll take measurement tomorrow and post it. I was taking measurement earlier but got called by my superior(wife..LOL). I know the injector housing secondary ports are opened up to 35mm. Not sure on the primary. It's has been years since I did the work. I did it back in '07.

[LGAFF]

Intake runner is too long, plenum volume is too small for the vehicle. Going to a sheetmetal intake is the solution...actually its somewhat already proven with Fastlanes car, the salt flat cars......a destroked LT-5 engine is making 560hp at 9K. Now thats alittle extreme in terms of setup(its using the lotus GT-1 intake) but the concept is there. Coyote motors are making 500rwhp right now...

[Kevin]

Kirchoffer made a sheet metal intake as well, looked awesome

[LGAFF]

and imagine that type of intake with Ron Hanselmans ECM

[XfireZ51]

and imagine that type of intake with Ron Hanselmans ECM

You mean a MegaSquirt right?

[FU]

The MegaSquirt uses the stock ignition module.

[LGAFF]

Correct....as I understand it there was a HP gain with the Hanselman ECM.....and not like 2-3hp...if I recall 10-15.


It all adds up..

[cvette98pacecar]

Intake, Intake, Intake:cheers: is the key!

Lee, I cannot agree with you more. There is no way anyone is ever going to get me to believe that our heads with (2)1.53" Intake valves would not breath as good as a big block with (1)2.10" Intake valve. our only problem is lack of space.
Oh, wait I have the Toledo pro hood. Extra 2.5" of space.