camaropower88

Hey everyone, I have a stock 350 TPI that i want to start building. My goal is to get at least 350 HP to the wheels. I have a budget of $2500. The car right now just has Hedman longtubes (68460), SLP Loud mouth I and LS6 injectors. What would be the best combo to get 350 rwhp? ported L98 vette heads with 1.6 roller rockers, FIRST intake, cam (need help here) and 3.73 gears to start?

camaropower88

views but no replies...anybody? would these 200CC heads(http://www.hawksthirdgenparts.com/ca...oldinpair.aspx) be big enough to get me to 350 at the wheels? or do i need bigger? or would the famed AFR 180 or 195's do just fine? what cam/intake would best compliment the dart heads, or the AFR's?

Abubaca

iTrader: (3)

I'd take some time and read, read, read. $2500 isn't a whole lot, and even if you can stretch it out far enough to get the right components, (which won't be easy) I'm assuming you're still going to be putting these parts on a stock bottom end with a lot of miles, no? Not a good idea.

My thoughts would be to take the $2500, and put it into the rear end, the transmission and the suspension. You're not gonna want 2.77 gears very long. 350RWHP will probably kill the 700r4 unless it's been upgraded, AND you'll want more than as stock torque converter. ...then of course you'll want to upgrade the old worn out suspension pieces that even when new, weren't up to the task of handling a 350 HP car.

Orr89RocZ

iTrader: (20)

Hmm, 2500 fo 350whp may be doable but you'd need to shop around to get deals to make this work.

You will need heads. Port L98's will do it but thats still gonna cost around a grand to have them ported, machined, springs/seals/retainers setup for the cam needed.

If you could find a set of used AFR 190-195's, Trickflow 195's, dart pro 1 200's, etc you could possibly do it for 2500, as those heads will cost about 1000.

You could get a set of profilers for about a grand but the components may not be best quality as if you got them from Speier racing or so other reputable head shop. With good valves/springs they are 1200 new, about same as AFR's if you get them through a member here who can get them for about 1300.

A 224-230 ish deg cam will do it easily with good heads.

Intake needs to be some short runner setup, like a single plane efi, miniram, or stealth ram or edelbrock pro flo xt. Single plane and stealth ram are likely your best bang for the bucks...can find a used HSR for 350 complete, you are doing good.

So you figure 250 in a cam, 1000 for heads, 500 for intake all used, 150 for walbro fuel pump kit, and then 250 for custom tuning equipment.... 2150 and left overs for miscellaneous small parts, such as gaskets/pushrods/rocker arms, etc.

If you could snag a used CC503 cam or CC306 cam from an LT1 forum for 150-175 bucks or so that will save alot more.

If you do TPI and want a FIRST, thats nearly 1100 bucks right there and leaves little for heads. I dont think stock L98's reconditioned will get there, but with a CC306 cam, that will push the heads to the limit and I'd be curious what you can get out of it. Still would prefer a short runner intake tho.

Marchosias

Orr.. you are great in advising and helping people with your knowledge

camaropower88

Orr you always have awesome advice! You are the man! but i do have a few questions for you. Will my trans and rear be able to handle 350 rwhp? Would the stock bottom end be able to handle it? Reason why i want to do this stuff now is because my valve guides and seals are shot. Im tired of the blue smoke. And if im gonna take the heads off for a valve job, no sense puttin money into stockers and all that work when i can upgrade! Oh and throw in an intake and cam while im at it

Orr89RocZ

iTrader: (20)

Where in PA are you?

Rear should handle it no problem but depends on how much you abuse it. I've pushed almost 700whp through my 10 bolts and they lived just fine, but they are 4th gen 10 bolts. I broke my factory 9 bolt rear with 220-ish whp So go figure, its kinda a crapshoot. The later year 10 bolts with 28spline axles are stronger than the earlier years 26 spline axles but not by much. Usually either the posi casing or ring/pinion gears break first.
9 bolt is suppose to be stronger than the 10 bolt but i've seen them break too.

Trans, if its a lower mileage unit in good condition it may hold 350whp for a while. Again, it depends on how hard you abuse it. I burned mine up at around 140K miles I think. Car was fine at 131 when I got it and within a year or so of me beating on it, (18 yrs old, first fast car lol) it broke in a street race. I rebuilt it for 1000 bucks, some 450hp level 2 type build and I put another 20K miles on it with bolt on motor, held up fine. THen another 1600 hard miles with a 400whp 383 and 4 bottles of 150 shots for over 500whp.


Bottom end will hold as long as you dont spin over 6200 rpm much. That a problem because with a big cam, you want to go to 6500. This is where a GOOD cylinder head comes in handy. You can make almost 400whp these days on stock bottom ends, with good heads and a high 220's deg cam, or even a 230 deg cam that will be done by 6200 peak rpm. 350whp can be had by 5800 and shift well before 6200 rpm.

So its abit more difficult to get to 350whp with a head that lacks alittle flow. My friends stock bottom end L98 with old school AFR 190's which are almost like a full ported L98 head in flow, made 330whp before suffering valvefloat with the 280xfi cam (230/236 deg) That car runs hard, but if it wasnt for valvefloat it would be a 350's whp car easily and peak near 6200 rpm.

Other guys here with new AFR 195's and same cam/HSR intake or similar are up near 370-400whp! The next sized cam down is the 268XFI that has been used on here alot, and its making 350's whp with full modded TPI based motors and good heads. Its very driveable and easy to tune, and done before 6200 rpm.

There are many cam combos that will work, it really depends on your heads. If you have good heads, you can run less cam. IF not, you gotta cam up

Blackdog36

iTrader: (3)

camaropower88, 350 rwhp is around 400-420 hp at the flywheel. Stock bottom end is iffy past 400 hp. Stock transmission is also iffy past 300-350 hp. Having an automatic transmission and non during burnouts or neutral drops will help save your transmission with that much extra power. Best bet for maximizing hp on a stock 350 engine is to get a holley stealth ram intake. It pushes power band up higher in the rpms vs a strong TPI setup. This will will make life easier for your stock rotating assembly and transmission. Stock bottom end won't like reving past 6,000 rpm. Something that we overlook or do not estimate in our quest for more power is tuning your new build. You will be spending some bucks for that $400-$600??

Many people have been on the same path as you and it is doable. Your HP goals might be a little lower than you like if you keep many stock parts. You can still build a mean little street machine though. Just research and plan, would stink to upgrade the same part twice.

Check out this article
http://www.gmhightechperformance.com...roc/index.html

Orr beat me to the post! I love TPI setups but it can take a lot of time or some $$ to make a strong runner. Don't want to discourage you either way.

Orr89RocZ

iTrader: (20)

Exactly, still a mean ride. With 320-330whp like most LS1's make, if your car is somewhat light, it will run mid lower 12's. 350 should touch high 11's if everything goes right

camaropower88

Well, I suppose I will find out what the weakest links are when they grenade haha. I guess Im gonna have to find the best heads I can get my hands on for a decent price. If i can get AFR 195's for a good price I like the sound of that AFR 195/HSR/268XFI combo. I'm in Philadelphia, PA by the way.

camaropower88

As long as I can KIND OF hang with stock LS1's, and curb stomp imports that think they are "fast", ill be happy. And also give my buddies 92 LT1 vette some competition

Abubaca

iTrader: (3)

I'm not trying to debate the accuracy of some of these parts and what they'll do as far as power, but 350 rwhp, on a stock bottom end, stock transmission, and stock rear end, doesn't seem like a good idea. Kinda like eating dessert before eating your veggies. ...BUT, if money's no object, I can't say I wouldn't be tempted as well! but with only $2500 bucks!?!?! I'm telling ya, it's gonna be sitting for weeks or months while you save for new parts.

Orr89RocZ

iTrader: (20)

Dont rule out profiler 195's either. Very good castings. Just needs outfitted with the right parts. Speier racing heads does them right at 1395 for the heads...some other places can be had cheaper with other components. Not a bad option.

camaropower88

Well, if its off the streets for a lil while it wont be too bad. I only work a block away WINNING! But I am definitely not done with this car after i put 2500 into the motor, I plan on upgrading trans/rear(hopefully before something bad happens)...I figure the bottom end will be ok if i dont over rev it. Ill just have to save up more money and baby it till i can rebuild the trans and beef up the rear.

Orr89RocZ

iTrader: (20)

Just be smart with it and it should live for alittle while. Tune is going to be important and keeping a rev limiter in it at 6000 or so wouldnt be a bad idea. My friends been running his to 6200 alot this summer and some last year and its still holding. stock rebuilt rear end, fresh 700r4, and stock bottom end L98 but new pistons (replacement)

Built it up as you go. I'm at 800hp and still have stock rear end...it takes time to eventually get everything done

camaropower88

well, found a pair of dart pro1 200's for $1295. best i could find so far, and its not even that great lol. Im snoopin around on LT1 forums right now to see if i can get a killer deal on a CC306 cam or something. I think the heads and HSR is gonna cost me the most

VincentZ28

iTrader: (2)

Burnout91 car made 397whp at 6300 with AFR's195, 280XFI Comp Cam, Fully ported HSR and with a stock 350 bottom end. There's also a guy that made 408whp with Trick Flow 195 Heads, 280XFI Comp Cam an a Miniram in a 355.

camaropower88

forgot to ask, define custom tuning equipment...lol.

camaropower88

I also want to ask if my injectors are too big with a 350 RWHP set up, i know they are way to big for the stock set up now. I have LS6 #28 injectors. They are rated 28 at 58 PSI and im running them at 32 PSI, and fuel trims are still a lil rich and i think that FP is too low. If i do heads cam and an intake will these still be too big? See Fuel Injector Connection was SUPPOSED to give me 22lb bosch III's...turns out they were 19's...car ran like crap. got another set from them and they were 19's again. Finally they said they were sending me 24 lb injectors and it turns out they are 28 lbs. So...if i need them for this set up i will keep them, if not i want my money back and i am going somewhere else!

Orr89RocZ

iTrader: (20)

28's are great for 350whp. WHen you go heads/cam just turn the pressure up to 58psi.

camaropower88

Awesome, I will just keep these 28's then haha

camaropower88

Just snagged a CC306 cam off an LT1 forum for $200. A little more than i wanted to pay but still cheaper than new. Now I gotta find a deal on a used Stealth Ram. More updates to come!

Orr89RocZ

iTrader: (20)

Thats a pretty big cam, but it is doable with a good tune. Thats going to be the hard part. Now depending on the heads, you'll get anywhere from 345-400 whp Modded L98 vette heads will work, setup for that lift. You can get vette heads for 300 or so and with 300 in machine work and springs,you'll have a decent head setup. really wants porting with that cam but it will "work"

camaropower88

My original plan was to use a set of ported L98 vette heads to save money, but with all the trouble of swapping heads and everything, I might as well do it right the first time and put on a set of aftermarket alum. heads on it to take advantage of the CC306. Aftermarket out flows ported stockers anyday! I think I can stretch my budget a lil further than originally intended

Orr89RocZ

iTrader: (20)

With better heads that cam will go to 6500+ I'd put the limiter on it at 6400 and shift it by 6200 to save the bottom end

camaropower88

But if it wants to go to 6500+ does that mean it wont be as effective on the lower end and mid range? As in not very streetable?

camaropower88

Also, would I have to swap to a torque converter with a higher stall speed?

Orr89RocZ

iTrader: (20)

It still will make good power from 3000 on up. It will love a higher stall with HSR, something around 3600 would work great, but a lower stall will drive just fine. Its all in the tune. Cam is pretty big so it will feel abit soft between idle and 2500-ish until things start kickin in.

camaropower88

define "soft" lol. It wont be TOO sluggish right, especially with the stock converter? Could i get it to work with the stock converter with a really good tune?

camaropower88

Maybe I should go with ported and worked L98 vette heads to help with the drive ability. Wont make as much power but will be more drive able

camaropower88

UPDATE: Been talkin to this local guy that MAY be sellin a BUILT 350 block with trick flow heads ( part number tfs-30400007). 350 block out of an 88 gta with a full roller valve train. .30 over bore, hypeutectic pistons, reconditioned rods, polished and champered crank, Comp cams 280/288 duration 576/570 lift, the heads are trickflow heads part number tfs-30400007 summit 1.5 ratio roller rocker arms custom length pushrods, moroso oil pan with high flow pump. Should make around 450-500hp.

he is selling this whole set up for $3000, i think i should totally do it!

or he would just sell the heads with the rockers for $1000...hmm choices, choices.

my thoughts are also to swap out that cam for the CC306 because that cam is FRIGGIN HUGEEE!

Orr89RocZ

iTrader: (20)

Ok, soft as in less torque. It moves torque band higher up into the rpm range. It wont have exactly the same feel below 2500 rpm as say a stock or mild cammed motor has. Its likely you can get that to work on stock converter. I had my buddy's motor working on stock converter with the comp 280xfi cam which looks like the same cam you mention in the motor for sale above.

CC306 is abit more rough on overlap than the above cam. If you bought that motor, i'd use the cam thats in it. It should have more low end than the CC306.

It all depends on what you are looking for. With the right gearing in the rear, once you get into the powerband, you will be staying in that powerband so lowend doesnt matter. Around town driving should still be strong enough and you will have that awesome cam lope sound with the cc306, so its nice on all levels. LT1 cars still put down good torque numbers with the cc306. It really comes alive above 3000-ish rpms like a LS1 car. IF you ever been in a LS1 car with stock converter you'll know what I mean. 2800-3000 rpm they come alive but feel kinda weak below that.

Putting on ported L98 heads wont necessarily help driveability. The smaller ports may have abit more port velocity and fill cylinders better off idle to 3000 rpm or so for normal driving but with bigger/better flowing heads and better port design, you can get great cylinder filling and make more power doing it.

So if you bought that 350 motor, i'd keep the cam thats in it, just watch out for those valve springs in the head, they may be too weak for that cam. They are dual 1.46" springs which only have 125lbs seat pressure and 365 open. I'd rather see closer to 150lbs seat and 400 open and a smaller diameter spring. We ran 120lbs/320 open and it lost control over 5700 rpm and that killed 20-30whp potential that motor had.

Ideally, a very driveable setup on stock converter that will make 350whp will be the 268XFI on a set of AFR 195's or possibly those Trick flow 195's. IF you bought that motor, sell both cams and get the 268 xfi and you'll have decent power, and great driveability. The other cams should make closer to 375-400whp on good heads. Just look at the 355 miniram/HSR thread, lots of guys making big numbers.

camaropower88

Very good info Orr, you really know your stuff! Well you have supplied me with plenty of awesome information and I really have some thinking to do now. If i buy that whole longblock, i still need to buy an HSR set up..and I already invested in a CC306. So now its gettin pricey. Maybe i should just snag the heads and rockers for $1000, use the CC306 and get an HSR. If i get those heads with the roller rockers for $1000, buy a HSR brand new($576), and use the CC306 ($200), my total spent would be $1776! If i could find an HSR set up used...that would be even better! Either way would leave plenty of money for a new set of roller lifters, pushrods, gaskets, and upgrade to 3.73s, and maybe a lil room for tuning. But on the downside im giving up a freshly built 350 block, which I am not sure is totally worth it, its basically stock except the pistons. Which is where I am stuck, would be awesome to have a freshly rebuilt block but...my wallet says other wise.

Orr89RocZ

iTrader: (20)

If he's willing to part out the heads, and you can get them soon, then go for it. Like I said, I'm not sure when I'll have my stuff apart so it may be alittle wait.

That motor is basically what my buddy has. reconditioned rods/crank with new pistons. He is selling his entire motor/topend that has a polished HSR on it. Real nice setup with 280xfi cam and the tune that I did (needs more work tho since valve springs were going bad). Not sure when he's going to pull it out tho, as he is going 6.0 lsx soon and I believe its ready to swap in. But it ran hard for basically stock parts inside. Its been turning 6200 rpm for 2 years now

camaropower88

Well, being paranoid about my stock bottom end, Im gonna buy the whole long block. It has only been run on the engine dyno at the machine shop. All i gotta do is slap an HSR on it and the ignition system and its good to go and swap in. Ill see how i like the 280XFI, if i dont like it i will just sell it and the CC306 and get the 268XFI just like you said Orr. Made arrangements to pick it up Sept, 2nd. I will be posting pics of the motor when I get it and pics of the whole swap. Gonna cost me more money but, its nice to know I have a solid motor that I can rip on pretty hard and not have to worry. And if somethin happens to this motor, i have a back up 350..its a win win in my book.

camaropower88

Sent me some pics of the block and heads

Orr89RocZ

iTrader: (20)

Looks clean! not a bad deal in my book. I'd run the 280xfi for now as it should have abit better driveability, but just be careful on the revs. It may float valves over 5800-6000 with those springs...wont know until you try it for sure, but seems alittle soft on pressure for that cam based on what my friend ran on his motor. If the heads are still off, it may be a good idea to upgrade the springs to something abit stronger. I know its more cost but its a worthy investment.

camaropower88

yeah the dude said the heads are off the motor so I will put in different springs just to avoid any trouble, would the AFR 8019's work?

91 zeee

Orr, suppose you built a motor that had 350 rwhp and went high 11's. That'd be awesome, but how would it run on a day to day basis? Would it still be a good daily driver? Do you think that much hp starts to make it too unreliable? Too many problems? How about cold starts in the winter and overheating in the summer?

I want to build a motor too (and I will), but I gotta admit, I love how good my car runs stock. I can start it up when its 10 degrees outside, put it in gear and drive off with no hesiatation or stumbling. I can sit in beach traffic on a 100 degree day and it does not over heat. It has been dependable for 138,000 miles. GM did a good job on all that.....how fast can I make it go without losing those things? 13's? 12's? 11's?

btw: thanks for all the advice to all of us on here...I have learned a lot from you......

Orr89RocZ

iTrader: (20)

Yes, those springs will work but you will need new retainers to match. Your springs on the TFS heads should be 1.46" diameter. IF you could find something around that size and with the pressures needed, i'd do that to keep it just a spring swap and reuse the locks/retainers.

A good kit for the money (~270) is the patriot extreme gold springs with titanium retainers. Similar to the AFR 8019's in size and specs. Need to order the kit for the LT1/sbc's as they offer a LS1 kit that uses 8mm valve stems instead of the sbc 11/32".

There are other springs that may work, i'd have to look them up.

Depending on how you do it and how much you can tolerate, you can go high 10's on motor with a 400+ inch motor and still start reliably But thats a very aggressive setup. If the tune is good, you can run pretty aggressive stuff and have no issues on startup no matter the weather and will run smooth all day long. It all comes down to the time spent tuning the car. I got my motor starting up in cold weather really well but it took some time because you only get 1 chance at it each day to do a cold start trial tune.

My 383 was aggressive but would idle stable enough in traffic, no issues. Drove around great and got decent mileage for what it was. Ran 11.4's. I'd daily drive it if it wasnt for the noise. It was a loud exhaust system. My buddy's heads/cam L98 is a big cammed car but it drives great. He has no issues but it does run pretty hot on the hottest texas days. That may be from lack of fan flow/radiator capacity. Hard to say.
Look at some of the california TPI guys here, running smog legal setups in the most strict state, making 390-430whp. They drive nice and pass smog. Cant complain there.

If you are looking for another 100K miles of operation, then that will change the cam and such to make it less harsh on the valvetrain. Should easily beable to go 12's and still drive mostly stock with longterm reliability. Good heads and a mild cam with good lift will do that. 11's will be abit harder to get to unless the car is super light weight. You'd have to work with a cam grinder to get a soft lobe that wont beat up the valvetrain but still give enough duration/lift to make power. Some of the marine boat lobes would likely work, as they are designed to run all day at high rpms and still make power.

You can have a high 11 second cars these days with a good set of heads/cam and intake. It all has to match well and the rest of the car needs setup right to get into that ET range. Suspension and converter/gearing. With some aggressive cams tho, you may need to change valvesprings out every 10-50K miles depending on how aggressive you go and the quality of spring.

91 zeee

Good to know.....
Hey, I am curious..... there was a guy named Atilla the Fun on here a while back (he got kicked off)...he seemed to know his stuff too, but I never found out what his backgound was (he always indicated he was some'famous' car guy)....any idea who he was and if his info was legit?

camaropower88

Well I think I found the valve springs I'm gonna go with http://www.jegs.com/i/Comp-Cams/249/...oductId=747961

Orr89RocZ

iTrader: (20)

Those should work nicely. They should work with the trickflow retainers as they are about the same size spring. Just need to double check the inside diameter to be sure. If not, just get the comp retainers for the 977's

Verify the install height on the stock TFS heads. I hope its no less than 1.80 and you can adjust. That 977 spring is 177lbs at 1.800" which is high. Setup at the recommended 1.85" thats 155lbs. That would work well.

camaropower88

Well I just gotta wait to get the heads to measure the installed height then. I cannot wait to get this motor in, the suspense is killing me! haha

camaropower88

Well got the CC306 cam in the mail today, lol. Guess its for sale who wants it??

camaropower88

Well, I made a replica of my engine as close to specs as possible in dyno 2003, and the CC306 cam makes better numbers and is a WAY faster time in drag 2003. For whatever reason the XFI280 cam wants to rev all the way up to 7500 R's! The CC306 makes peak 466HP(flywheel) at 6000 rpms and starts to decline after 7000. That is right about where i want it. The 280XFI on the other hand peaks only 416HP (flywheel) at 7500 RPMS. Max torque on the 280XFI is not even until 6000! Max torque on the CC306 peaks at 4500 at 446lb/ft. But still makes 373lb/ft at 2000! So I dont know how accurate this dyno2003 program is...but the CC306 looks like a better option, has a good torque curve, makes more power and makes the power exactly where i want it, between 6000-7000.


heres a pic of the CC306:

Orr89RocZ

iTrader: (20)

I dont know about that...something seems wrong there. All the DD models i've made show them close together. ON a 350 with a short runner intake and good heads, both of them will want to go to about 6500 rpm. The 306 may hang on abit longer with its higher exhaust duration but the powers should be similar. Maybe abit more torque with the XFI due to less overlap and faster valve motion, it may make more low end torque.

Make sure you have the cam specs right and set it up to calculate power based on .050" numbers not advertised duration

camaropower88

Well I cant get the right specs for the valve timing, i need the specs for valve timing at .050 lift, comp gives the valve timing specs at .006 lift...

89Firebird355

I recently built a 355 SBC the cam has a .555 intake lift, .535 exhaust lift. Sportsman II 200cc heads solid lifters 1.5 ratio roller rockers and a tpi intake which i put into my 89 firebird. The stock ecu wont run the motor right. I cant get it to idle below 1500 rpms. How can I get the motor to run right?

Orr89RocZ

iTrader: (20)

Need to burn chips for it Depending on duration it should idle at 1000 or less.

Enter in these for the cams.

280xfi. 280/286 advertised, 230/236 at .050" 109 intake centerline, 113 lsa. .576/.570 Using that it will calculate valve events:
ivo 6 ivc 44 evo 55 evc 1

306. 290/307 230/244 .510/.540 with 1.5 rockers. .555/.576 with 1.6's. 112 lsa, 108 intake centerline. Most comp cams want 4 deg advance. Using those you should get.
ivo 7 ivc 43 evo 55.5 evc 8.5


Desktop dyno LOVES large duration split cams for some reason. Now I know some engine builders like alt of exhaust duration on higher output motors/race applications even on heads that have great intake/exhaust ratio flow. I ran a custom grind that was like a CC306 on steroids in my 383 and I loved it. BROAD hp curve. it was within 10 hp i'd say from 6000 to 6800 rpm with peak at 6250-6350. Wide duration splits do that.

XFI will make good peak and good overall power but should fall off after peak alittle. Not a problem, just have to dial in shift points