Ok LTX peeps,

I am trying to get the most that I can out of my 94 Z28 without having to get crazy with the bottom end.

I have all the bolt ons, now just thinking about putting together a beefed up version of the LT4 Hot Cam Kit.

I have the LT4 Intake Manifold ported for a 58mm TB, I have a set of mildly ported LT4 heads, and was going to go with the GM 847 cam.

I am hoping that will get me in the 11s.

Any thoughts or suggestions?

 

yes, put your fire suit on and prepare to hear about AI and LE to the point of nausea.

or look at the weekly threads made about this exact topic

 

what size stall you using ?

 

There are some folks who will give you the blind praise you want.

When you are ready to ask questions before committing to mediocre decisions the rest of us can help.

 

Before I would build a stock shortblock I would make sure the bottom end is in good shape and has good oil pressure. What is the oil pressure at idle with the engine fully warmed up?

 

If your in the 12's with bolt-ons i think u should be giving us advice. And u should know making hp is in the right combination of parts. So your going bigger with the 847 - is a much, much bigger cam - with the same compression is gonna lose on the bottom end. U could have the heads flat milled - and would then need to have the intake milled to fit also - to bump the c.r. for the larger cam. U can have heads angle milled for even more compression also but not many shops do that anymore.

Im reading u want to use a stock bottom end. The weak link here is the stock LT1 rods bolts - they wont take the higher rpm of that big 847 cam - larger heads adding power too.
My advice is with the LT4 heads go for a shorter cam but on a tighter lobe separation angle to build more torque in lower rpm. Something like the Hot Cam (0.050" duration) with 108-110 LSA. That should make use of those larger LT4 heads and let the bottom end live.

cardo

 

I made it to 11.6 with stock short block, XFI 280 cam, home ported heads, 3.73 gears, 3600 RPM stall, and the usual bolt on's. The car weighed with me in it 3750lbs with a DA of around 800 if I recall correctly. I made a thread years ago on cz28 about wanting to do the same thing you are trying.

 

i have lt1 383 with all arp bolts and eagle rotating ***. lt4 hot cam lt4 heads ported lt4 intake ported 1.6 roller rockers 58mm tb. that thing runs great and i can run it up to 7000 rpm. (i part these cars out i 1993-2002 i have 35 cars in parts)

 

If have the motor apart id def do arp rod bolts, mains, heads.

 

That sounds pretty close to the combo I just put together. Any links to info (time slips, dyno numbers, threads)?

I would be pretty happy with those results. Mine only differs in 3.90 gears and 3350 race weight.

 

http://www.camaroz28.com/forums/lt1-...ch-11s-710144/

 

You should send the heads out to a good porter, they are a great start. The 847 probably isn't what you want though. You'll want a new converter too or refresh them.

 

Most intelligent guys who run those heads will say they are wrong for a 350/355 held within the pcm's 7000rpm limit, and that is from the people who like them.

 

So GM engineers dun goofed with making the LT4?

 

Supercharge it.

 

Kinda mute point here as the OP doesnt participate. More like a troll that tries to get everyone to spill their guts while sharing nothing. Why bother folks? Too bad we dont have real moderators that would clean these trolls out.

 

I have a 2800 stall with a TH400 trans at the moment.

 

You guys need to lighten up a bit. I've read alot of the posts and see what people do and don't do.

Just trying to see if anyone has done anything different & possibly learn from mistakes made when beefing up the top end.

That's what these forms are for right? Helping each other out?

#LTXfam

 

https://ls1tech.com/forums/4048412-post6.html

 

What ever you do limit your RPM's to 6400. I bragged about taking mine to 6800 for a couple years, then I found the weak point, rod bolts. I think I got lucky with a healthy stock bottom end the first time.