Ok I am about to begin a small side project. I am going to convert a 1972 Porsche 914 over to SBC power. These cars are very light and their transmissions can't handle all that much power. I have a few guidelines for the engine.

Must be between 290-300hp. (flywheel)
Must be between 315-340ft lb torque (flywheel)
Needs to redline around 6k if possible
Needs aluminum heads
Needs Fuel Injection

These are my only restrictions. The reason for the power restrictions is basically because of the fact that the transmission and clutch can not handle any more power without some heavy modifications. I need the aluminum heads to save a little weight. The 6k redline deal is because I would like to be able to use the stock tachometer which redlines @ 6k I know this sounds stupid but I don't want to have the interior of the car up and it would be great if I could just have the redline the same as stock.

Now I plan to build this engine from the ground up and do all the labor myself. What I need to know is what items I will need to make this thing have a good power curve and not be either all torque or all HP. It will be driven on the street every weekend and may see a few auto-x events.

Price is not a huge concern but I prefer to stay below $4,500 if possible.

I have never built an engine before and I would like to build this one right.

I will be starting the project with a brand new GM 350 4-Bolt Main block. I need opinions on what parts I will need to make this setup meet my guidelines. I need suggestions for a cam, heads, fuel injection setup (Edelbrock?) and all that stuff.

Please post your opinions everything is helpful!

Thanks,
Dustin



[Modified by 69-912, 12:20 AM 2/19/2002]

 

That will be easy. The hard part will be staying under 300 HP!
A GM crate motor with 2 bolt mains, iron crank, and 91 to 93 throttle body will be 1500.00 out the door at Pace or one of the other volume crate motor dealers. Toss the heads and install a pair of aluminum vortec heads that will set you back about 850.00.
Need a carb. and insist on 4 bolt mains? Same deal but the motor is only 1275.00.
I would strongly recommend that you go with the throttle body and do the custom wiring with a kit like the Painless. the throttle response will be worth it.

 

1979: Ok thanks for the help.

I was thinking about somthing like the Edelbrock EFI setup.

 

Stock TPI should be cheaper and meet your needs. Have you searched the sporty car sites for information on possibly upgrading your transaxle? Cool plan, have you looked at the size of the all aluminum Cadallic Northstar V8? Power should be in the range that you're looking for.

 

Speedways motors sell complete Caddy motors for $3k new.

 

Man, with a 350 and alu. heads you are going to have a hard time keeping it under 300HP! Well, here goes my stab at it.

L98 alu. heads aprox. $500-$600 rebuilt
GM TPI system $1000 if you go to S&P or less off ebay
Comp. Cams XE268 hydro cam should give you 6000rpm redline
9:1 compression to keep the power down (dished pistons)
small-tube headers

Here is what I get with dd2k:

325HP@5500
374LB@4000

You can put in a bigger cam to save the tranny (drop the torque). Trannies don't care about HP (Lars told me this, so it is true. He used to work for GM).
If you go with an XE274 and the Edelbrock injection:

347HP@5500
364LB@4500

The 274 will have a bit of a lopey idle and might have some vacum problems. The only way to get the HP down at this point is to put some crappy heads on it or a restrictive exhaust, but you would kill the motor. The L98 heads "out of the box" aren't going to flow allot on the intake side anyway. Probably the best choice on your engine to keep the torque down. You would pick up about 15 HP and 5 LB with a bowl port job on them with this setup. You just have too big of an engine. If you drop to a 327 you would be able to get into the HP and torque that you want without having to choke the motor. You would have almost the same HP with less torque but the peaks would move. Just my two cents.

 

Wow you guys know your stuff.

I have rethought this situation and came up with this idea:

Would it be possible for me to make a 302 like a DZ302 using the 350 4-Bolt block? Which crank would I use and what other stuff would I need? Any special rods or pistons?

I figure a 302 should make a little less torque which is what breaks stuff :) and as a plus it should be a little more rev happy.

I could do a 302 with some aluminum heads and a FI setup what do you guys think and what would I need to make the 302 from the 350 block? :chevy

 

Ok guys I've been playing around with Engine Analyzer a little and figured up this combination:

350 Block 4.00" Bore X 3.004" Stroke
Edelbrock Performer RPM Heads (Box stock not ported)
Edelbrock RPM 7102 CAM 1.5 Rockers
Edelbrock Performer RPM Pro-Flo FI

I'm coming up with around:

355 Torque @ 4800 RPM
350 HP @ 5600

Thats a decent baseline. Now I just need to figure out how to get that torque down a little. I figure the transmission can probably handle that much HP if it's freshly rebuilt.

Any opinions on this setup? Would it be streetable?