I have pretty much completed my 408 build. All I have left is to purchase the fuel injectors, fuel rails, throttle body, and the remote mount oil filter, then stick it in the car.

My builder speced the cam and with my build he says I should be making 600 crank hp. I am a little sceptic of that number and am looking for more input on what you think the hp will/should be. I built the engine for nitrous at this time and to switch to turbo in the future (with a cam change). I am not looking for what it should do with the nitrous or the turbo, just NA all motor guesses please.

Here is the build..
4.030 bore iron block
4" Eagle shaft
Eagle rods
Ross piston (-12cc revers dome turbo/nitrous)
Compression Ratio (Static) should be betwwen 9.5:1 and 10:1 (There is a little confusion here)
ARP studed mains with ARP capscrew crosstie bolts
L92 heads custom ported
GMPP Single plane alluminum manifold with EFI provisions (not ported)
Edolbrock 110 degree short elbow (to mount throttle body to the carb style intake)
327cfm flow at 0.600 lift threw elbow, manifold, and head on a 4.0" plate
GMPP "Cadilac" lifters
ARP capscrews for heads
Factory rocker arms (temporary)
balanced, decked, torque honed
Camshaft is a custom cam from Chette Herbert 230/240 .593/.602 Lobe Center is 114 and intake center line is 114
IVO (BTDC) 1 IVC (ABDC) 49 EVO (BBDC) 54 EVC (ATDC) 6
All cam specs at 0.050"
Moroso oil pan (this thing took 8 quarts to fill and it is still on the engine stand!) wich requires a remote mount oil filter.
SLP high volume oil pump
Cloyes double roller timing chain
underdrive pully (SFI)
SFI Flexplate
Hooker headers (large tube), no cats, offroad "Y" pipe, muffler with two outletts.

Going with the Wilson Manifold's 90mm throttle body (I have not purchased this as of yet)

I think I got it all in there.
So what are you seeing with simular builds?

I need to know so I can decide on my injector sizing.

Thanks guys.

 

Were did everyone go?

 

If you have a Moroso LS1 oil pan, then it is a 6 quart pan. I would not put more then 6 quarts plus what you need for your remote oil lines and filter. Mine holds 7 quarts with my remote lines, filter and reads at the bottom of the "add" on the dip stick tube. I called Moroso and they said a stock tube doesn't read correctly with there pan.

 

Yes, I thought it held more then advertised. I took my bore scope, pulled the crank sensor out, with the engine on the stand and checked the fit of the dipstick with the moroso windage tray and wide panrails. It just clears it all. I did this without oil in the pan. I still have it on the stand so I will pull the sensor again, bore scope it to see were the oil level is relivent to the widage tray and give a report back as to what I find. I bet the oil level is up over the tray with the eight quarts in it.

 

Please let me know what you find. I had a 408 very similar to your Only stock L92 heads and it made 505 rwhp with a 6 speed with a max effort tune.

 

I will let you know. I am going to try and look at it today. 505rwhp is very exceptable to me. My goal with this engine was to make no less rwhp all motor only, as compared to my present engine with the 150 shot of nitrous. It currently makes 475rwhp with the juice. So if I can make 505rwhp all motor then I will be very pleased. Once I finish the fuel system, I plan to shoot a 250 shot of nitrous on it until I have finished gathering up the stuff for the turbo.

 

Your motor should like the bottle and with the low compression level your heads are going to stay down better.

 

OK, I just finished bore scoping the engine with the eight quarts of oil in it. The oil level on the new factory dipstick is right at the top of the full mark. I went in threw the crank sensor hole at the rear of the engine. I could see the windage tray/crankshaft side all the way to the front of the engine and the oil level dis not come over the tray. I found a hole in the tray to pass the scope and once threw it I could see the oil level and I could see the dipstick in the oil. It is hard to judge distance with a borescope with nothing to refrence to, but I would say that the bottom of the tray to the top of the oil level is a little more then the length of the twist in the dipstick. Keep in mind the dipstick does not go straight into the oil, it enters the oil at about a 45 degree angle. I would think the level would be lower while the engine is running. From what I can see I would say the 8 quarts with this LS1 Moroso pan I have (I think they have an earlier version pan) is good. The only other way I can think of to check if the dipstick is correct is to remove the pan and see if it changes the angle of the dipstick to the block. I was concerned in the begining that the pan and windage (due to the wide flanges on the pan) would interfere with the dipstick, and cause the oil level reading to be incorrect. That is why I borescoped the engine the first time. Looking with the scope I can not see any place that the pan or tray is touching the dipstick, and the dipstick does go below the tray. I do not have any info from Morosso on what they say the pan holds. Again after looking at everything, at this time I feel the dipstick level is correct. If you have the same pan as I, I bet the dipstick is reading correctly.

Yes, we think the lower compression will let us run more timing with the nitrous then normal, and once the turbo is installed, we are hopefull it will be turbo friendly with a good strong pre-boost pull. I plan on trying this cam with the turbo and see how compatibale it is. If it turns out to not work well with the turbo I will replace the cam.

Thanks for the info. It has been a long build, and at this point in the game it is nice to hear from others with similar builds. Knowing thier results helps to ease the nerves.

 

Good information. Why are you using the windage tray as an acceptable level? I have never looked into an engine with a bore scope so I'm not sure what the factory levels should be. Here is the only picture I have of the pan. Is yours the same?
http://i271.photobucket.com/albums/j...8/IMG00099.jpg
http://i271.photobucket.com/albums/j...8/IMG00274.jpg
http://i271.photobucket.com/albums/j...8/IMG_0922.jpg
The last picture is just for fun as I just took the picture............lol

 

110* elbow, big turn. ~10 cr?

460 RWHP A4

480 RWHP M6

 

i say around here as RWHP

435 @ 5500
455 @ 4500

 

I'll guess close to 550 at the crank. I think you might need a little more cam duration to see 600 crank HP. With heads flowing over 320 cfm, I would think closer to 245 intake duration will get you to 600 HP naturally aspirated. You'll have no problem getting over 600 HP with the turbo or nitrous. The 230/240 cam will be fairly streetable. Isn't bench dynoing fun?

 

True and to our amazement it did not hurt the flow threw the intake and head. The intake manifold is what hurt the flow. We had the head up to 340 cfm, but the intake knocked it back down to 327 cfm. There is some confusion with the compression ratio. When we ordered the pistons I could have swore we calculated 10:1 but 6 months later when I picked up the engine the builder thought it was more like 9.5:1. So I am not sure which it is any more. Either way it should work good with the nitrous or turbo.

 

I am not realy using the windage tray as an acceptable level, I was thinking the oil level might be over the windage tray with the 8 quarts, and or the windage tray/ oil pan rails might be touching the dipstick causing it to bend up some and give a bad messurement. I am realy thinking that if the windage tray and the pan rails are not interfering with the dipstick, then the factory dipstick level should be a good read and can be trusted.

 

Yes, I am also thinking 600 is a stretch. If I was not planning to eventualy put the turbo on it then we would have went with a much more agressive cam and bumped the compression ratio up to at least 11.5:1. that would have made for a very nasty toy. I bought a new pickup to pull the car to far off tracks. I am now thinking about putting the turbo on the truck (it is probly to big to use on the truck) and sticking with the nitrous in the car. I wish I would have built the engine with more compression now. It's to late for that now.

As long as it makes better then 475rwhp NA I will be pleased, and if it makes 500+rwhp NA then I will be estatic!

 

Yes, it looks to be the same. Sweet ars engine. I wanted to go with the Beck, but the wife would not let me spend the money. Kick ars ride too!

 

The L92 heads only flowed 340 cfm..4" bore? Alot of ported L92's are in the 365 cfm range. Either way, you be good on the spray.

Yeah, the power of the LSx engines will always be killed by these damn plastic intakes. Great heads flowing 400+ cfm, then they get knocked back to mid 350's or less with these intakes...it sucks. A porter down here gets over 400cfm on his ported LS7 heads, then with the LS7 intake they flow around 350-360cfm. More than 50 hp left on the table.

 

The port work is just a pocket clean up. More to make them all match. There was no point in going any farther with them seeing as how the intake kept holding them back. No point in waisting the money porting them all the way when the intake hurts them. Plus doing so can give you a negative result. Yes, the plastic intakes are a real drag. Thats why I went the single plane carb style route. I remember when I bought this car new from the dealer. The "new" space age intake was one of the selling points. What a joke it turned out to be.

 

No matter how you go, turbo or nitrous...............the exhaust side needs a lot of attention when it comes to the LSx heads. They really are the weak link. With nitrous your compression ratio is fine but the exhaust side is going to struggle if they are left stock. A lot of nitrous people don't pay attention to the exhaust side, don't match the cam to the flow numbers and then wonder why there cars are slow. Good dyno numbers but weak track times!

 

I do know the porter did alot of work on the exhaust of these heads. I do not know the numbers, but he also is the one that spect the cam after he completed the head work. You are right, head work first then the cam selection.