Like it says guys.

What would be needed.

I want to run the cast L98 heads (will modify), 355 short block with flat tops, Comp xe282hr or xe288hr cam, With my Team-G intake, holley 750. Is it possible to get 400+ hp out of this combo?

If not what would it take. Maybe some vortec heads?

Engine funds went south, I need a new plan. 375 hp I could live with, but looking for 400 at the flywheel.

thanks guys for your advice.

 

You will have to port and polish the L98 heads very well. Follow the link at the end of my sig for instructions.

One hp per cubic inch is more likely all that can be relatively easily attained. Once you go past that mark on a naturally aspirated engine your low rpm hp curve must be traded for a lumpier camshaft that will make more high rpm power. That does not make for a fun street engine at all, since at least 95% of your time is spent below 3000 rpm.

 

You will have to port and polish the L98 heads very well. Follow the link at the end of my sig for instructions.

One hp per cubic inch is more likely all that can be relatively easily attained. Once you go past that mark on a naturally aspirated engine your low rpm hp curve must be traded for a lumpier camshaft that will make more high rpm power. That does not make for a fun street engine at all, since at least 95% of your time is spent below 3000 rpm.

 

Thanks for the info on the head porting. I just need to get up the courage to break out the grinder. I would hate to ruin a good set of heads. lol.

Can anyone run this combo on DD2000? The rest of my mods are in my sig at the top.

thanks.

 

You won't ruin them. It takes deliberate effort to port cast iron and unless you are Arnold Schwartznegger you are not going to wreck them.

 

Here is what the graph looks like with stock L98 heads. Take these numbers with a grain of salt, as these are supposedly dyno numbers with no accessories at all running. So this would be flywheel numbers on a stand, under PERFECT conditions.

 

was that the 282 cam? also my team-g is a single plane.
looks like around 375 hp.

Also is those stock L98 flow #'s or ported ones? Aluminum or cast?

thanks

 

Yup, the 282 roller cam. Sorry about the single plane--I used the dual plane option but it won't make a huge difference. Supposedly stock L98 heads, but I believe they are really using the aluminum Vette L98s, due to the 58cc combustion chamber. Flow numbers are the same, regardless, and the heads require a good port and polish to routinely support 375 hp.

Personally, I think it would be lucky to make 330 hp. DD2003 is even more generous than DD2000 in its power estimates. Compare this one's numbers to a ZZ4, which I believe has superior parts yet is only estimated at 350 hp.

 

I had though about going with the vortec heads or a good set of dart Iron eagles 200cc.

I do have a scat 383 crank sitting in the garage that a friend gave me. All it needs is turned and polished. Im just afraid that the ported L98 heads would hold back a 383. What do you think?

 

Nope, the ported L98s will do just fine on a good 383. Get Vader's templates and form the runners to them. As I said, iron heads are hard to ruin unless you are a muscle-bound nincompoop. It just takes too much physical effort to bore through into the water passages, i.e., hours on the same runner. It happens but most people who do it admit that they knew they were pushing the limits when they went through. If you stick to Vader's templates, and my instructions, you WILL get an excellent set of heads that can support up to 450 or 500 hp.

No kidding.

PS F-Bird'88, who is the one who taught all of us about porting these heads, has one guy running a healthy 400 ci mouse on ported and polished 416 305 castings, and he isn't complaining.

 

That is nice to hear. I think I will try p&p the heads, maybe go to 2.02 & 1.60 valves. Swap in a cam, torque converter and trans work and go racing.

I may get to the track friday and see what new times I get. Then I can get a base line to compare.

thanks.

 

The heads don't respond well to 2.02 valves. 1.60 on the exhaust is OK but stick to 1.94 on the intake.

 

So then it would be a waste of time putting the 2.02's in? Why does it not help? not trying to be dumb or anything.

 

F-Bird'88 experimented with 2.02 valves and it either slowed the flow or didn't help at all. Also, 1.94 and 1.60 valves take up about all the room in the combustion chamber.

 

thanks for the advice.

 

SittingBull, What do those DynoSims cost and best place to get one?