Just got the car back, runs awesome (even though I'm keeping it under 3500 rpm's and it's loud as f***), and I got this information sheet with specs on the motor...Honestly a lot of it is greek to me, but tell me what you think...


Cylinder Head Data

Valve Dia Intake: 1.94 Exhaust: 1.50
Chamber CC's:56

Block Data

Average Bore Size: 4.042

Piston and Ring Data

Piston mfr/type: J.E. Forged

Top ring gap: .020 2nd: .018

oil ring .030 Piston to Deck Clearance: .025

Camshaft Data

Cam mfr/type: Crane Roller
Hot Lash: Hyd.
Lobe Lift-
Intake: .302 Exhaust: .310
Camshaft duration @.050" lifter-
Intake: 214* Exhaust: 220*
Gross lift with 1.5 ratio rocker-
Intake .452 Exhaust: .465
Piston/Valve clearance-
Intake: .200+ Exhaust: .200+

Misc:

Total Cubic inches: 357.234

Compression Ratio: 10.5317

 

Seems like an odd combination... stock valve sizes, slightly larger than stock combustion chamber cc's, and less intake valve lift (0.425") than a stock LT1 cam (0.447")? ? ? ? ? The lobe lift x 1.5 doesn't match the quoted valve lift ? ? ? ?

 

Hmmm, maybe they wrote something down wrong. The cam is bigger than stock, so I don't know why it would have less intake lift.....it is lopey at idle.

Either way, I've got a ton more power and I haven't even gone WOT yet. I'd say maybe 60 RWHP or more over stock, based on the butt dyno. Real dyno in maybe 3-4 months when I can get on a new TB, SFC's and get a madz28 tune.

And I asked for a mild, smoggable upgrade in case anyone is wondering why I didn't "go big".

EDIT: Wow I must have had a weird dyslexic type moment, just rechecked the sheet and got some numbers switched around...

But still .....Not much bigger than a stock cam on the lift huh?

 

must be a typo or something. Very common with working with fast paced shops.

 

Stock lift with 1.5X rockers is 0.447 I/0.459 E. You might want to think about switching to 1.6X roller rockers. Now that you corrected the gross lift numbers, the math works out.

 

What is loud about it?
Is it a clattering, a deep thumping like someone is rapping a hammer, sound like a diesel motor, what?

Judging by the cam and compression you got this from someone who does not know the LT1, would have been further ahead to ask questions BEFORE rather than after.

 

sorry, the motor isn't loud, it's the exhaust....I just meant to say that I'm very happy with the performance, but it's too loud for me. The TSP rumbler is just a slightly bent straight pipe....what was I thinking..

I'll probably do 1.6RR a year or so down the road. I honestly can't not afford a penny more right now.

Thanks for the input. Do you think I've gained 60 or more RWHP?

 

Im in the process of building my 357 right now also. It isnt a HUGE cube motor but I have seen people with some good gains off it.

Did they just not touch the heads? I dont see anyone using stock valve sizes if theyre having the heads worked over.

I am going with LE for my head/cam setupm so mine SHOULD gain good numbers.

 

Depends on the heads. I know when I went from a mild cammed setup to the current heads and cam I gained like 100rwhp still keeping the untouched stock shortblock. Power is in the topend not bottom though most guys seem to have a hard time understanding it. Mine are ported 95 Camaro heads, the porting is just really good.

 

The heads were worked over - rebuilt and ported, not sure why the valve sizes are stock. Like kaj said, could be a typo on their end, maybe they had the stock numbers in front of them as well as what they did and put down those on accident?

Maybe I will get on the dyno before your build is done and you can get a rough idea on what you'll make (you'll make more with an LE package)

Thanks for the tip 96caprice, I'll have to try to remember that in the future.