View Full Version : All right, heres the new combo. tell me what you think
travis Jul 16th, 03, 05:27 AM My credit card is smoking, by the way :D
388ci, pro-topline iron lightning 200cc heads w/72cc chambers, wiseco 2vr flat tops (-5.4cc's), scat cast steel 3.75" crank, scat forged rods, comp 294s, weiand 7530, 750 edelbrock (for now), 1 5/8" headers, dual 2 1/2" flowmaster force II system w/h-pipe, roughly 3400 flash stall 10" ATI, heavily beefed th350, 3.73's, eaton posi, and a MSD pro-billet HEI. Should come out around 10.3-1 compression, and should work on pump gas. I was going to use my isky 247/254 solid, but engine analyser didn't like it at all with these heads...caused a big loss of low end that didn't catch up with the 294s until over 4K, and then the gains was just a couple of hp. I also have a set of 1.52 and 1.6 magnum roller tip rockers, but I think the pro toplines use a 7/16 stud instead of a 3/8"...so I may need to order rockers too. A better carb may come later as well (after the credit card cools off) depending on how it does with the edelbrock. I think my street tires are going to hate me :D
67RS502 Jul 16th, 03, 06:21 AM I'd say its a good combo accept for the headers and carb, get some 1 3/4" (since it will
make more then enough low end tq) Clean up any rough casting in the bowls if there is
any - this makes a difference everywhere! A 750DP would be good, get a HP 950 if you can.
Get some roller rockers for it. I'm not sure what intake the 7530 is (stealth?), run a 1" open
spacer. I think it should make 450-475hp/500tq with these changes, and put your car deep
in the 11s on tires. ;) Keep us posted.
Rubeng442 Jul 16th, 03, 07:36 AM Since you already have the magnum rocker arms use them, you might even want to do a litle testing and try different intake/exhaust ratio configurations. ;)
The headers do seem a little too small, might want to step them up to 1-3/4", get good collectors, no bigger than 3" on the 1-3/4" and 2-1/2" on the 1-5/8" headers.
Cam...I am not sure how close the engine enalyzer can really be when comparing camshaft profiles. Does it have inputs for adv., .050, .100, .200 durations? If not, then it cannot really tell what the cam will do for the engine. I know there are better profiles than the 292S out there, but since you already have it I do not see the need to change it. It should have plenty of power.
Eric68 Jul 16th, 03, 07:42 AM I like it too. the 750 Edelbrock should be fine IMO, a double pumper might go a hair faster though. I also like the 1-3/4 headers.
ps. The ProTopline aluminums with 200cc runners and 64cc chambers were cut for 3/8" NC threads in the head. We installed 3/8" studs.
travis Jul 16th, 03, 08:17 AM Thanks for the replys. The headers probably will be changed to 1 3/4" but I will leave the rest of the exhaust alone for now. With all these pretty new engine parts I sure hate to leave this old crusty headers on the car ;)
67RS502, the 7530 weiand is basically the same thing as the edelbrock vic jr 2975, but it is about 1/4" to 1/2" shorter I have heard. Since I don't have the money for a cowl hood right now, I have to try and stuff everything under the stock hood. I *think* with my drop base 14x3 air cleaner it will just fit.
The plan with the rockers is to use what I have now IF the heads come with 3/8 studs...but the website says 7/16...we shall see.
And I know you can't base everything off of engine analyser 3.0, but to date it has been suprisingly accurate (ain't that right, Eric?). The pro toplines have an excellent exhaust port, and because so, the simulator says it will hurt low and midrange power, which I believe. There was several reasons I picked the 294s...1, I have used comp cams products for many years and have always been very happy with them. 2, its a gentler solid cam , so it should live a long healthy life and not beat the snot out of the valvetrain, and 3, there is a truck running around here with a 11-1 350 and the 294s cam and flowmasters and it just gives me goosebumps every time I hear it :D Plus, it runs 11.80's in a '67 chevy lwb with a 3500 stall and no n2o...so it can't be that bad ;)
67RS502 Jul 16th, 03, 08:42 AM Sounds like you have a team G, which is ok. Something I dont believe, or should
I same I know is false - if the heads have an excellent exhaust port, then they will
definitely not hurt the low/mid range, just the opposite, the good exhaust ports will
help in scavenging the cylinder better especially in the mid range, as long as its an
efficient exhaust port which flows well, and not a "big" exhaust port which flows well.
Now youre gonna have even more low/mid range - aint strokers and good heads fun?
If the exhaust ports are really good then try 1.6 rockers on the intake side.
travis Jul 16th, 03, 11:54 AM 67RS502, maybe I should have clarified. Yes, it is the 7530 team g power ram. Virtually identical to a 2975 vic jr, but supposedly ever so slightly shorter. My point about losing midrange (not like I KNOW it will happen, just what I've read) was using a relatively tight lsa and a dual pattern cam. It would have been perfect with the vortecs I was going to use. Here's the flow numbers per pro-topline (take it for what its worth)
lift........int........ex
-------------------------
.100........71.........57
.200.......146........101
.300.......203........157
.400.......249........177
.500.......261........186
.600.......269........190
I could be wrong about losing midrange...if so then I have another cam to try ;) The next problem will be getting enough tire under it to hook this monster up. I can't wait.
Oh, as far as the carb is concerned, you said the 950hp holley would be worth a shot. I was thinking about getting a 830 annular holley hp series...is that the same carb? Per David Vizard, the annular discharge carbs are the only way to go, offering stronger low end response from the booster design over a comparable down leg type booster. Any thoughts on that? Scroggins-dickey has a awesome price on the 830...under $400. Of course that has to come later...I got to get it running first.
Eric68 Jul 16th, 03, 01:06 PM "And I know you can't base everything off of engine analyser 3.0, but to date it has been suprisingly accurate (ain't that right, Eric?)."
I'll say. I think you were the one that put me onto the 294s and predicted an 11.8 ET. Pretty darn close if I do say so myself . . .
67RS502 Jul 17th, 03, 05:18 AM 7530, I'll have to check but I think I have one sitting on my work desk in the garage,
waiting on some plenum work. (yes I have a desk in my garage, doesnt everyone,
right next to the compressor!?) I looked at it and wasnt too impressed, a victor jr
is a better design and would make more power, also I think a RPM would make
more power, but its not a bad intake - good for low hood clearance.
I think a dual pattern would work good with these heads & a 2 1/2" exhaust, and
if its on a 110LSA, like most Comp stuff, then it will work good too, but could make
more power with a tighter LSA.
My point was that a good exhaust port wont make you loose power, but if you had
the wrong cam for it - that could.
11sec. cars arnt too hard to hook on a good tire (ET street) you should be fine.
HP 950 uses a 750 body & a 850 base plate, so it acts like a 750 as far as throttle
response and drivability. Never tried a 830, but the boosters are supposed to help.
You can piece together a 950 with Proform parts - body=$99, base plate=$125,
Holley jet plates=$50ea, then you just need some fuel bowls! Just over $300 -
what a deal!
travis Jul 17th, 03, 07:38 PM So, bottom line, which do you think would be the better cam to use...the comp 294s (248/248@.050, .525 gross lift, 110/106), or my isky solid (282/288@.020, 247/254@.050, .507/.525 lift, 108lsa, no advance ground in, .016/.018 lash). Just looking at the numbers, the isky actually seems to have milder lobes than the comp cam. Maybe with 1.6 intake/1.52 exhaust rockers? The dual pattern might even work better with the smaller headers...I dunno. Should I run it 4* advanced? FWIW, the isky is ground on a small base circle, but the rods are already cam clearanced, so either way I won't have any cleance trouble.
One more question. I need an oil pan. The milodon pans look good (especially with the built in windage tray and rear pan baffle) but I don't know if they will clear a stroker crank. Moroso's similar pans will supposedly clear, but I like the look of the milodons better :rolleyes: Any thoughts?
Pistons should be here tomorrow or saturday, then its off to the machine shop monday or tuesday for balancing. Block is done, tranny is done, everything is here except for the pistons, heads, and comp cam/lifters.
Eric68 Jul 18th, 03, 02:33 AM On the cam - with the ProToplines strong exhaust port, I'm not sure the dual pattern is really needed, but I like the tighter 108 LSA. I also know that the 1.6 rockers work well with the 294s in my setup to make roughly .560" lift --- if the heads flow better up there that might be the way to go. I do like the 1.52/1.6 idea on the Isky cam too . . . shoot, you already have it why not use it? I just don't think that there is that much diff between the two.
On the oil pan, I bet they would both clear . . . but that's just a guess.
Rubeng442 Jul 18th, 03, 08:22 AM Given your 73% average I/E ratio the Isky does not seem like a bad choice at all, plus you already have it. Use the 1.6 on the intake to take adavantge of the high lift flow of the heads. The exhaust should be fine with the added duration.
Figure out your DCR to see if you should advance the cam and how much. Although the actual "advertised" duration of the cam is going to vary with lash, making it a little more difficult to tell the exact valve timing events....
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