Hi, I'm new to this forum. I've been reading through some of the past posts, and it seems like you guys know alot about the L98 engines, so maybe you could help me out. I currently have 257rwhp and 373rwtq with a 383 stroker with everything stock that is listed in my sig. What would you recomend for a heads, cam, and intake setup? It's between AFR 190's and an LTR setup or a SR and AFR 195's and a miniram. I love the low rpm pull and uncontrolable wheel spin but I want it to pull harder past 4500rpm than it does right know. Does anyone have a similar setup with dyno #'s and et's.

Thanks

 

Anybody out there?

 

I'm running a 1986 TA with a 383. When I originally installed the motor, it had ported Edelbrock heads, LPE 219/219 cam and SR. The best et was 12.00@113.5. I have since gone to AFR 190's, Comp XE solid roller 236/242 and a MR. The car now runs consistent 11.6@118.

Once I pull the car out of storage, I will do some fine tuning on the fuel curve. About a month ago I picked up a wide band air/fuel meter which will help get the fuel curve nailed down. I'm not making excuses but I know of guy's running the same combo that are turning 11.40's at 120+.

Just a word of caution, a big cam with a MR means hp peak in the 6400-6800 rpm range.
www.geocities.com/dzperf

 

Thanks for the reply. What kind of RPM's do you peak at? Did you lose a noticable amount of lowend torque with the MR?

Thanks

 

The MR did shift the power curve up. There's no doubt that the SR made more low end grunt. When I intalled the cam and heads, I upgraded to a Vigilante converter. It stalls somewhere around 3400 rpm. I have no regrets about going with the MR. It has a good flat torque curve with an awsome top end especially when paired up with the solid roller.

www.geocities.com/dzperf

 

I dont know how much you know about this, so dont be offended.

First of all, your 305 block can not be made into a 383. You must start fresh with a 350 block which is bored 30 over. Also, the block will have to be relieved for the larger stroke (3.75" vs 3.48" stock). So basically, you are talking about a complete new motor. You can buy assembled crate engines or you can buy an engine kit that you assemble yourself.

Watch out for one piece rear main seals vs 2 piece rear main seal blocks and cranks, they are a match set. If you buy a single piece rear main seal block, get a crank for a single rear main seal block. There are conversion kits, I think to run a 2 piece seal crank in a single seal block (but it might be the other way around).

I recommend that you buy the latest issues of GM High Tech Performance and Chevy High Performance magazines. Check out the various speed shops that sell 383 stroker kits.

If you intend to install a supercharger, you should buy an all forged stroker kit. I think that they range from about $1300 to $1800. Also, watch out for your compression ratio. With the addition of a SC, you should run a slightly lower CR but I dont know whats right.

Anyway, these are just a few decisions that you must think about.

Doc

 

Just my $.02.

For the price of the miniram or superram, I'd switch to a converted LT1 intake instead.

I ran an 89GTA with AFR 190's, superram, crane 2032 cam, 383, 9:1 compression and ran 13.0's at 106 mph. I bought the car with this cam and heads. It dynoed 300 rwhp at 4600 and 380 tq. The car had a couple of bad lifters, cause I just swapped cams and replaced the lifters, and the car doesn't idle rough anymore.

I just bought an LT1 intake myself to have converted, after I get the new combo running good.

With your stock ported heads or trick flow's and the LT1 intake, you can pick up some more power.

The superram is a good intake, but I wouldn't buy another one with other alternatives out there now. I've already spent $500 bucks getting it fully ported and flowed, and for the hassle of putting it together along with the cost and benefits, it's just not worth it.

 

Thanks for the help guys. By the way my GTA came with a 350 not a 305, I know that a 305 cannot be bored out to a 383.