I am using a engine out of a 92 Z28 which is a 350 and I plan to have it bored and decked....I plan to put GM Vortec heads, GM vortec manifold, Edelbrock Headers, Holley TBI, TBI Spacer, K & N and I have a SS hood that will let the air hit the K&N directly..... How much Horses would you estimate I would be putting out? Has anyone done something similar?

 

what cam?? if its the stock cam, im guessing right around 270-290 @ the crank... maybe 300.. i think im being optimisic too...

 

It would be the cam they used in the L98, what other cam would you suggest.......

Would it make that much of a difference in power......The only problem I would encounter is making sure it would stay in the legal limits with smog or just good enough to pass.....

 

I'm working on the same setup, except i'm using a roller motor. The numbers I come up with are 320 HP and 425 ftlbs. Thats with CompCam's EFI roller cam with 1200-5200 RPM range. You will need a higher pressure fuel pump and an adjustable fuel pressure regulator to get the fuel required to get these numbers. You will also need chip tuning.

 

Cam specs and heads?

 

it all depends on how streetable you want it... if you have to pass smog, youre pretty limited as to what cam u can use... LT1 or LT4 cams are pretty common and make decent hp thru all rpms... im not much of a walking parts catalogue like other guys on here, but maybe some of them will chime in with cam numbers for ya

 

Heads are vortec (062) with .500" crane springs.

Cam is:
Camshaft Specification Table
Part Number 08-302-8
Engine Chevrolet 305ci-350ci

Grind Number CS 264H-R12
Description
Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.48 0.48
Duration At 0.006 Tappet Lift 264 274
Valve Timing At 0.05
Open Close
Intake -3 33
Exhaust 46 -6
These Specs Are For The Cam Installed At 108 Intake CL
Intake Exhaust
Duration At 0.05 210 220
Lobe Lift 0.32 0.32
Lobe Separation 112
Recommended Valve Springs 981-16

My numbers were figured using 9:1 CR, Small tube headers, ~670cfm TBI, and cylinders bored .30 over.

I am also depending on the accuracy of Dyno2000.

 

So what numbers were you putting out with that setup? 264hp at the rear wheel?

What do you guys think about the Holley TBI? Is there a better route without having to convert the fuel setup drastically?

 

.320 lift @ .05?

 

0.320" lift is the lobe lift of the cam. 210/220 deg duration @ 0.050" lift. Multiply lobe lift by 1.5 or 1.6 to get the lift at the valve.

 

Power will vary any where from 280 to 425 depending on the cam size. The higher the horsepower the more fuel your going to need. With the l-98 cam you'll probably need the 65 lb/hr cop car injectors and maybe some fuel pressure. Anything more and the 90 lbers would be needed. Not many people have gone much past 380-390 horse so your in pretty deep once your to those numbers. You'll HAVE to get into chip tuning for this motor, too much stuff has been changed to just crank on the fuel pressure.

All this is in vein depending on the type of smog testing you have. vortecs don't have EGR ports, so you'll have to plumb the egr to the GM intake that has the provisions for this, and this still might not be legal depending on the smog ****. DIY tuning will be the only way to get it to pass.

 

What is DIY tunning? Can I still get over 300 horses while still using a TBI setup? I figured the Holley TBI would help but I thought that using the TBI setup would be the biggest weak point.........

 

Any type of fuel injection is going to be weak if you can't tune it. When I talk of DIY chip tuning I'm talking about actually going into your chip with some specific software and changing things to better suit your engine. Think of it as being able to change the jets and timing curves on an old school engine, only with a million times more control and acuracy. Check out the DIY prom board, start with Traxion's intro to prom burning it's in the stickies at the top of the page. If you still have questions after reading it a few times, feel free to ask, but you should make sure you do a few searches on your question first to make sure it hasn't been covered a million times.

The holley TBI is a step in the right direction if you can tune for the added air and fuel, it's only one part of the equation.

 

Yall make it sound so easy.

In short, yes it's necessary, no, just reading Traxion's article will not even begin to cover it.

 

Hey, I never said it was easy, I just pointed him to the source of the info he needs to get started. I like to leave the decision as to whether or not it's too hard up to him. You will have to admit that this thing isn't going to run right without some work, be it prom work, or swaping to carb work.

Just for the record, prom burning isn't for everyone, neither is skiing, swiming or jumping rope. Just make sure you feel confident you can learn the ropes before you order the equipment. Also for the record, I no longer ski.

 

So you're saying you "jump rope?"

 

LOL, no I read the instruction manual and decided it wasn't for me.

 

I decapitated the next door neighbors cat before I learned it wasn't for me either.

 

What do you think of the JET chips? How much does it usually cost to get a chip custom made?

 

They suck. Too much.

 

I paid $1k for a custom chip and it still was way off. For less than $200 you can get the software and hardware for chip tuning.

 

$1K?!?

I've had 5 custom burned chips done for $200. Smokin' some of that purple haze were ya?

 

It was that much because they tuned it on a dyno. Probably a lot of dyno time I'm assuming.

 

For 325 HP, you'll need injectors running about 80lbs, and this (theoretically) can be achieved with 65lb injectors running at about 16psi. Running a vacuum referenced fuel pressure regulator dialed in to hit this psi should do (according to what I've read and calculated)

BTW, this info is specific to 2 injector TBI's, the numbers will be different for a 4 injector holley.

 

No gunny I do not partake of any medicinal inhalants.

The reason it was so expensive is because it was done on a dyno that is charged at $150/hr.

And was it worth it.......NO!

 

words of wisdom learned the hard way