well after 3 years of keeping my vette stock i finally have the urge to dig in and wake up this lumbering beast of an L98 i have

my plans: keep the stock shortblock
looking for heads
looking for a roller cam

undecided on an intake as of now, but it will obviously be something different than TPI

what i would like is somewhere in the area of 400-450 crank horsepower

would like the car to still be streetable, but would like to turn some quick trips down the 1/4 mile

also thinking about 3.73 or 4.10 gears as i now have 2.59's

judging by what i have seen on this forum, everything seems feasible together

just looking for pretty much a proven combo to go with

 

That's going to take an additional 150~200 HP.
I think you should start looking at a 383.
You can turn your engine into one fairly easily.

Another route to get to your goal is a supercharger.

For about the price of the supercharger system you could build yourself a 383 stroker using your L98 as the base for it.

My preference is a N/A engine so I'm building a 383 for my '91.
Actually it will be a 388 CID.

 

I think that before you decide on which heads and cam you want to use,you should settle on which gears and intake you will be using.That way you can have evwrything working together at the same RPMs.

 

well, i value your opinion about the 383, but after reading what people are making with head/cammed 350's i dont think i need to go that far

not too crazy about the supercharger idea, especially on a high compression, stock shortblock
i think i would be boost limited and would only gain maybe 100HP safely

lets put it this way, after having a sedated, ho-hum 250 HP corvette for the past 3 years, now i would like to have some fun

right now i am thinking about 195cc Trick Flow heads and either the GM LT4 hot cam or the LPE 219 cam (although i do not see this listed on lingenfelters site anymore)

my buddies 383 LT4-headed, hot-cammed stroker is turning timeslips that would be equal to him making about 460HP\
i believe those heads flow about 235/240 cfm.................so i am thinking with heads that flow slightly better (260ish) i should be able to reach my goal with a 350

i am still kicking around the idea of which intake (mainly because only one is emissions legal because it has EGR)

which brings me to another point............does the hot cam have enough overlap to take the place of an EGR valve? knowing that it was designed for the LT4 (which does not have an EGR valve) and i believe i read it is a 50 state legal cam....................?

i think i will leave the gearing dependent upon what engine/ intake combo i choose..........although i am thinking 3.73's or 4.10's (which might seem like a little much, but remember, its time to have fun!)

thanx guys!

 

ttt

would like some opinions...........

 

Cam lobe profiles have come along way from Gm,s and LPE ,s older offerings. Nowadays you can have quite a bit more lift for a given amount of duration vs these older units(call comp cams). Its hard not to go 383 or larger, its not just horsepower, keep torque in mind also.On the heads dont just concentrate on a peak flow figure( low and mid lift figures count for a lot also), but instead use the average flow figures for comparisons.

 

true true...........not really interested in a 383.....although that probably is the hottest type of street motor right now............just wouldnt be in the budget to do that much (and do it right)

i guess instead of stating HP figures i should have said that i would like to run low 12's at the track on all motor

i am right in assuming i need about a 195cc intake port though correct?

what about GM fastburn heads? i heard they can make some crazy power and are pretty universal

 

well if you need a carb number for your intake due to emissions that leaves you with the super ram. and if you want to keep your stock block then its going to be a 74219 cam, 1.6 rocker arms, heads, headers, exhaust, 58mm throttle body, chip, etc and step up to a 3.07 gear.

You should get about 400 crank hp with a properly set up and tuned top end with the super ram.

Enjoy.

 

http://www.eportworks.com/

http://www.advancedinduction.com/AiContact.html

 

You want that power out of a 350 I think your intake is already chosen for you: miniram.

195cc heads will be needed, and I wouldnt use Fastburns. Id go to something that flows better.

Hotcam will be too small, though if you read Nathan Plemons' page you'll see that you can max it out far enough to get close with an LT1. L98s with a MR would be fairly equivalent.

 

thanx for the help thus far.........it is really appreciated

195cc heads...........trick flow or AFR?.............LT4 hot cam is considered pretty small for these heads, huh?

you'll just have to excuse me bringing up these outdated cams and such, i have been out of the loop for a while

i'll be honest, i'm just really looking for a known good setup that somebody has that i can copy........

 

If you plan to make 450 crank hp, you will need to decide on an intake manifold first.
Some of us have been trying diferent combo's for many years to get the most out of them. The l-98 stuff is very difficult to get big hp numbers. Big torque, but not big hp. The lt1 and miniram guys have the hp advantage.

 

I agree w/the mini but I also think once you start looking past 400ish at the crank you will want a biiger cam (ZZX 226/226 @50 or something in the 220/230ish duration range). I think even then and w/comp. ported heads, 1.6 rockers etc. you might get 425-440 or so out of it at the crank. Since you don't state anything else, to ET the car and IF an A-4 , you will need some other tweaking, including a reasonable upgrade in trans. and converters, gear, tire, etc.

 

Although the 3:73 and 4:10's seem like a fun idea, the 700r4 trans will make 1st gear absolutely useless. Regardless of the power in front of the trans, the 3.08 1st gear in the 700 will make for horrible traction.

 

like i said earlier, carb number needed: get a super ram lower and upper manifolds, 58mm throttle body, a good set of heads, 74219 cam, headers 1 3/4", exhaust, tuning, etc will get you 400 crank hp.

I do not know if the miniram has a carb number or not.

 

regarding the post above (which is good advice), i'd stick with a 48mm stock TB, and go for 1 5/8" headers, for a 350cid.

 

dont need a carb number as they never open the hood, just has to pass the sniffer test

was actually thinking about a converted LT1 intake............price is reasonable........its comparable to the mini-ram and i think i even saw a fellow make an EGR valve work with it

like i said..its doesnt have to be 450HP..........would like somewhere in the 400-450 range........hell i would be happy with 400

like i said i would like to get low 12's in the 1/4 mile

 

well bottom line, on a 350 a super ram will get you about 400 hp, if you want 450 and maybe more, then you need to get either a lt1 conversion, miniram, or efi/carb intake swap. No doubt about it w/o forced induction.

if you dont mind messin with the super ram then i'de go for the 219/sr/afr combo with "the works" (tune, exhuast, etc).

If you want a simple package to maintain then go for the miniram or the lt1 conversion with a matching cam and definetly a gear change.

what kind of budget are you looking at?

 

Give these guys a look. They are professionals for heads and cam combos. www.advancedinduction.com Let these guys figure out whats best in reguards to what cam should be used. This is what they do.

 

budget is approx $3K give or take (i'm doing the work)

i see what you guys are saying now with these EFI cars.........you kind of have to backwards engineer the heads/cam to which intake is going to be used (for lack of a better way of saying it)

i am leaning more towards the LT1 or mini-ram.............


thanx once again for all the help, keep it coming