SiCkRs

iTrader: (6)

What cam would be good to get me around the 300hp with a 350tbi also if i could use stock lifters even better.

88gta3508

you should be a lil more specific and what is your real goal???
are you going to leave everything else stock????
are you going to tour america or race, drift, road coarse???

SiCkRs

iTrader: (6)

OK sorry about that.
This are my goals:
1. Would like to keep up to LS1's so i am thinking i would need around 300hp
2. I am also thinking of putting a carb intake and put an adapter for the tbi
3. It's gonna be a daily driver but also taken to the track once in a while
4. What other mods would be good other than the headers, cam, and the exhaust.

88gta3508

thats a pretty tall order with a TBI to match a LS1
if you carb it you will lose half of your fuel economy VVVVVV
I would get a LT1 intake setup you will need real gears 3:45 - 3:73
24 -26 # injectors... i would get better heads... your stall is a start
it's your choice in cams i would get something like a Comp cam 08-305-8
and you have a roller compatible block..this is as big as you go with a stock converter...

this would be a great start but you would need to get a TPI wire harness

if you carb i would go Qjet 650 & something like a duel plane stealth ram intake
carb cam something like the Comp cam XE274H.. non roller block.. going carb you lose bottom end HP...gain the upper end

you will need Compression for these cams to work!! 64cc Heads
it's fun to convert if you have the time.. and money

bluers91

First you should really only use the stock lifters if they are roller lifters. Do you already have this 350? Does it have roller lifters? That will help you to know which type of cam you should start with

What heads you choose will help to determine which cam you should pick to get to your 300hp goal. For instance, if you have good flowing heads like Vortec heads or other aftermarket heads you wont need as big of a cam to get to that HP number if you have a full exhaust and a good tune. In that case something like an LT1 cam could get you pretty close. If your heads dont flow as well you will probably need a bigger better aftermarket cam.

SiCkRs

iTrader: (6)

So there would be no way to get to the 300hp with the tbi or is just too pricey

SiCkRs

iTrader: (6)

Yes i have the 350 block already and just bought some replacement lifters its a L98 block from an 89 iroc

bluers91

It is possible to hit 300HP with TBI and many people on this forum have done so with some work.

Do you plan on using the Stock L98 heads? If so you will need an aftermarket cam and a good tune to get 300HP. I would personally use a set of Vortec heads with the LT1 cam. If you can afford it go aftermarket you could do better.

Look at the L98 stock specs. With a TPI they are 245HP / 345TQ. The TPI does make more tq in the midrange over a TBI though. Add Headers and a full exhaust and it should be up about 20 - 30HP. Add a better intake and pickup some more power. Then add a nice cam like the Comp listed above and you hit your 300HP or real close to it. You will probably need a better fuel pump, more fuel pressure and larger 2" TBI unit and injectors as well like the 454TBI or Holley.

Hope that helps.

SiCkRs

iTrader: (6)

I had my heads rebuilt soi am going to stick with those what cam would you recommend me also wouldsome roller rockers help out more. As of intake what would be a good one.

88gta3508

roller rockers are luxury they will give you a true 1.5 ratio.. they will help the valve tips.. and run very smooth..but you will never notice HP I would stay away from aluminum.. if you do buy them.. your 350 heads.. they are 76 CC you will not have enough compression with the cams I mentioned.. you would need domed pistons.. but you need to choose keeping TBI??? upgade to TPI, LT1 intakes or carb ???

thomas1976

He has a L98 long block from an 89 iroc, heads are 083 casting with 64cc combustion chambers.

bluers91

How do you plan to tune this thing? If you pick a cam with too much duration it could be harder to tune. You probably want a cam without too much lift either if you just did a basic rebuild on your heads. You may also need to change out your valve springs after picking a cam.

How about something like this. Very reasonably priced for a Roller.
http://www.summitracing.com/parts/TFS-31402000/

DD2000 shows 325HP / 375TQ with 9.5:1 compression with a dual plane intake and headers with mufflers. So being conservative take off 20HP and your around 300 or so with a decent tune and 2" TBI unit.

thomas1976

I would not go any lower then 112 Lobe Separation (degrees). For the tuning.

SiCkRs

iTrader: (6)

on the tuning i was going to get it from tbichips.com

SiCkRs

iTrader: (6)

any one stil thinking of doing this

SiCkRs

iTrader: (6)

Anyone I already saved up about $300 for a cam and I found out I have a 87 block not 89 sorry about that.

bluers91

If your heads are setup for higher lifts and I had that much to spend I would look into the Comp XR series. Something like the XR262, XR269 (CS XR269HR-12), XR270 or A ZZ4 cam would be cheaper and could get you to your HP goal as well and you could invest the rest in a better TBI unit. This is all assuming you have a roller block & roller lifters.

SiCkRs

iTrader: (6)

So I should get this then http://www.jegs.com/i/Comp%20Cams/24...0002/-1?CT=999 and with a good tune I might reach what I want.

bluers91

That appears to be an upgrade for a ZZ4 crate engine. There isn't really any info on the cam specs either and its probably not very computer compatible. I was thinking more along these lines which should be better for your tuner to dial in properly.

DD2000 shows around 330HP@5000 / 420TQ
http://www.jegs.com/i/Comp-Cams/249/...59#moreDetails

DD2000 shows around 350HP@5000 / 420TQ
http://www.jegs.com/i/Comp-Cams/249/...59#moreDetails

A stock ZZ4 cam shows 380HP@5500 / 410TQ. You may be able to pick one up for about $100 used. It may be harder to tune than the first cam.

These numbers assume you have L98 heads, 600cfm, headers with mufflers and 9.3:1 compression.

You really need to know what lift your springs are setup for on the heads you had redone.

SiCkRs

iTrader: (6)

How can i the lift my springs can handle and were can I find the zz4 cam.

bluers91

Find out from whoever rebuilt your heads what they are capable of. If they are stock springs they probably will need to be changed out to handle anything > .450 lift. Anything above .480 will require special retainers or guides cut and / or screw in studs. Anything more than .500 lift should have screw in studs to avoid pulling out a pressed in stud.

Here is a ZZ4 cam with springs and retainers found in the classifieds here:
https://www.thirdgen.org/forums/engi...ler-cam-w.html

Here is a ZZ4 I found on Ebay.
http://cgi.ebay.com/ebaymotors/GM-Pe...Q5fAccessories

SiCkRs

iTrader: (6)

I think I still have the stock springs because the heads looked he same since when I took it to them and is it hard to replace the springs or would I have to take it to a shop to do all of that for me.
Thanks for that post I just pmd him hopefully he responds back.

bluers91

In order to replace the springs you will need special tools and I think they need to be measured and shimmed properly. Its probably best to have a shop set them up to be safe. I have the same dilemma with a pair of Vortec heads I have. I also have an LT1 cam to go with them, but am debating whether to go with something bigger. Going bigger like ZZ4 means dropping down more $$$ to have the heads setup properly. This is where you may opt to go with a lower lift cam which will not require the expensive setup of the heads but that may not meet your power goals.

SiCkRs

iTrader: (6)

Around how muh would a shop charge me to fix my heads for I can drop the zz4 cam

bluers91

That is hard to say. I would call a couple machine shops in your area and tell them which cam you plan to use and how much to set that up. You could always put in a cam with less lift like an LT1 or Ramjet and be right around 300hp. The TQ however would still be pretty nice around 400ftlbs. Those would be much easier to tune as well and not require a ton of work on your existing heads.

SiCkRs

iTrader: (6)

Oh ok I thought the lt1 cam was almost the same as the l98 cam bit I will go check on the shop how much they will charge for that I hope
it don't get to expensive at the end.