View Full Version : Engine question
jcaldwell
12-31-2005, 01:55 PM
Ok I don't know a whole lot about piston engines. I know how they work and all but when it gets down to specific numbers and crap about the engine I don't really know what it means.
So I am loooking at getting a '95 Z28 with this engine:
383ci LT1 4-Bolt Splayed Lunati Main Caps 0-Decked Block
4.030" Bore 3.75" Stroke
5.85" Connecting Rods (for no oil support rings)
SRP Forged Pistons - N20 Gapped Rings
Forged Crank and Rods are from Lunati
Lt4 Fully Ported Cylinder heads from Sunset Racecraft. 2.0" Intake valves, 1.6" exhaust Valve. Valvesprings for .525" lift. LT4 Intake Manifold.
GM LT4 Hotcam w/ 1.5 Rockers
Now the guy has spray on it and it put down like 530 whp with a 150 shot. But if I decide to get the car the spray will have to come off (my mother is my insurance lady :thumbdn: ) so I was just wondering how this engine would run without the spray. Any NA hp guestiamtes?? Thanks
Jeff
grandkodiak
12-31-2005, 02:17 PM
All that jumble just lists the compenents and dimensions of the stroker job... 383 means that the displacement has been increased from 5.7L (350 cubic inches) to 383 cubic inches... the bore and stroke measurements just show what exactly was done to obtain this... bore is the diameter of the chambers and the stroke is the length of travel for the pistons in the chamber.. the longer, the more air, the bigger the displacement... the wider the chamber, same deal. the connecting rods i'm assuming he put in are just to fit the stroker better and are probably stronger then stock... the srp forged pistons with nitrous gapped rings just means that the pistons in there have been replaced and are stronger to take more abuse, and are better suited to handle nitrous without failing or allowing blowby. same goes fro the next line which just says that the rods have all been replaced with stronger ones. these are all the usual when you stroke a motor... your in there, might aswell replace everything with stronger components.
the lt4 fully ported yadda yadda is describing that the cylinder heads are either from an LT4, or have been ported to match LT4 specs (a version of the LT1 motor that the SS and Firehawks had which produced a few more horsies from better flow), the measurements given just describe the cylinder heads specs, valsprings have to do with the heads and cam, showing that they are opening alittle more for better flow then stock, and the lt4 manifold is just a improved lt1 manifold. its all intake crap.
the last line means that the camshaft has been replaced with a nonstreet version of the LT4 camshaft... slightly more aggressive then the Corvette LT4 stock cam profile, and the 1.5 rockers means that the rocker arms push a ratio of 1:1.5 for added valve lift.
i suck at guessing numbers but that sounds like a strong motor... i would have gone with a different choice on the cam by far with a 383 setup, but whatever. i'd say you have a good 400+ to the wheels without the nitrous... but you could see far better if you ditch that LT4 hotcam for one to match your 383!!! i'm sure someone more informed will step in right about here:
TransAm45
01-01-2006, 06:21 PM
Yea that setup will put around 400 to the wheels (without spray). A slightly bigger cam would really be better with the 383. That whole setup could cost around $4000, even more with spray, if you started with a stock LT1.... That may help if you are wondering about the price..
GOODZ/BADZ
01-02-2006, 03:12 AM
Swap that cam for a custom grind and those stock ratio rocker arms for some 1.6's. Get the heads fitted with 2.02" valves too. That thing will scream. :burnout:
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