?? for a 358 combo
 

I am helping my friend put together an engine and for his S10 and we are stumped. The S10 is a weekend ride only, no DD for this setup. Some of the parts listed below are from the previous build, but did not last, as the cam lobes, and lifters where not properly matched. The problem is I dont understand where the line is drawn for choosing a cam, and by that I mean HR or SR, ie....max potential of HR for HP & RPM and or where to consider a SR from that point. The idea is to make more than 475 flywheel hp for the setup. Also can you give me some feedback on my current thinking that the duration of the cam directly affects peak hp as lift affects the torque peak and curve? :shrug:
For a HR I was thinking something around 230's duration for intake and upper 30's for exhaust with 550 - 590 lift. Had an example cam 230 / 238 569 / 588 112lsa ( lift given with 1.6 rockers)
I do not have any information for a SR so that is another area you could give some enlightenment.
Lastly, I also need some help in understanding what lifters to use once the cam has been chosen, for HR are there any lifters I can use that are not retro fit lifters? And for SR, just the top 2 choices for a lifter.

I also dont know what fuel pump is currently used but maybe you can give a pointer or thread to read about fuel requirements. *Fuel pump is stock intake regulated for carb.*

List of Components:

.40 over 350 4bolt main block
stock crank - Now forged Scat 3.48"
LT1 PM rods - Now forged Scat 5.7" 7/16
SRP flat tops 11.1
ARP main and rod bolts

Dart Pro1 230cc heads - unported
64cc chambers, 2.08 / 1.60 valves
1.55 dual springs good for 630 lift Angle plugs

Crane Gold 1.6 rockers

Weiand Team G manifold - unported
Holley 750 double pumper
MSD Pro Billet distributor
MSD Blaster 2 coil

TH350 rebuilt with new clutches, etc.
10" 3k Holeshot converter

7.5" rear with 4.10 gears 28 spline axles, Eaton diff ( Have to use till 9" is done)
1.75" mid length headers, 2.5" H pipe, 2.5" exhaust to dual flows dumped before rear axle.

Weld Draglites 15 x 3.5 F
Weld Draglites 15 x 8 R 275 / 50 / 15 Drag Radials
2.5" Cowl hood
Hey thanks for the Advanced info guys...

Call me an idiot,but Im not seeing the question your asking here...?

Are you wanting to know what type of cam to use?

If your racing it,use a solid lifter cam...solid roller would be even better.

Yes, my questions are:
1. Where is the line where you cross from HR to SR with a setup like that?
2. What is the relationship between duration and peak HP with lift and torque for the cam?
3. Can I use a HR in that setup and achieve the goal of over 475 flywheel hp, or do I need to use a SR?
4. The example that I use for a cam 230/238 569" 578" 112lsa , how does that the bill for making 475+ hp?
Hopefully that clears things up.

Soild lifters are for high RPM.... 7,000+. And for very high spring pressures.

Anything else that can be added?

It's fairly simple. He needs to decide what rpm range he is building a motor for. With the current state of HR and valve train technology I would consider the "corssover" point to be somewhere in the 6,500rpm range. Much above that and more hp is available from a SR setup. At or beolw, an HR will make as much power and be easier to maintain, as well as not having some of the SR related durability problems when operated at low engine speeds. Looking at the heads and manifold, I'd guesstimate that they might support 7,000rpm. On that basis, a SR would seem to be the way to go. However, he needs to be careful that a cam with too late an intake closing point is not chosen, as his static CR is not very high. Also, the springs will need to be matched to the cam, whatever choice he makes.

Rich

Ok, so for the HR setup we need to match the springs to the cam, but with the lifters, most the retro fits have the link bars since you cant run the dog bone - spider piece. Do you think that style of lifter will be able to handle 6500 rpm?
What do you think about the HR that I mention in the previous post?

I run those heads on a 396sbc with a super victor/carb
254/260 duration @.050" .620" roughly, on a 110. Shifting at 7000. solid roller also,Comp tie bar solid roller lifters.

With a 358, it could want a lot more rpm. No reason it wouldn't be making good power at 7500/8000 with a 270/280 duration cam. With 26" tires/4.10's/3 speed trans..:eek: My solid has been very good to me. No adjustments needed yet in 2000 miles and 50+ track passes. I check it after every track day/cruise weekend. Something in the 230/240 duration range might get it done, I'l let someone else chime in here.

If the engine is apart I'd at least put some scat 7/16" cheap I beams in it. I'd then spin the crap out of it and not worry so much. Goodluck!

New update....
The stock rods and crank have been ditched for Scat 7/16 rods and Scat 3.48" stroke crank. So the bottom end is all forged materials. Now for the cam, the machinist recomended the Voodoo Solid Roller
237 / 243 566/ 578 and I am not sure of the LSA for that. The listed RPM range for the cam is 2500 - 6800. I am also not sure if that is for 1.5 or 1.6 rockers but the setup is currently for 1.6 rockers...so if that is added in it will be 603 / 615.
I would appreciate any thoughts on the specs of the cam, and is the converter enough for this cam?

nope

Crap...:cry: I kind of thought so, what do you think...somewhere in the 3500 - 4000 range?
What about the cam? Is that a good choice for around 475 fwhp?

Ditch the Vodoo cam and have a convertor built for your combination, no offense but you have an odd ball combination from the small cubic inch to the large 230cc heads to the small 2.5" exhaust to the extremely weak 7.5" rear and then couple all of that with a 26" tall tire. Your going to need a real special convertor to get all that stuff to get moving quickly down the track.

If you haven't purchased the heads yet I would recommend going down to the 215cc heads if you raise your compression to 12.5 or more, and if you don't raise the compression I'd look at the 200cc head offered by dart.

or if you don't have the lower end yet and you have the 230cc heads already I'd look at building a 383 or larger stroker engine to better use those heads with.

With your combination of parts your hp goals are going to be tough to reach and it will be very weak down low.

I would just put it together and replace stuff slowly......

starting at the back.....

You need more tire too a 26" tire is just not going to work. You could cut down any rear and put ladder bars on that truck cheap. Depends all on what you want to do......just be aware that the combination needs to all work together, its kind of hard to guess at it. I would get it together and fix the problems as you find them

what do you already have? How much money can you spend on top of that?

Ha! Tell that to the Real Street guys! :D