HPE is assembling my Lunati 383 this week, and I have a few induction system Qs. Here's my setup: FAST 90/Nick Williams 90, 42 lb/hr injectors, ET stage 3 5.3 heads, (64cc, 230 cc, 2.055/1.570, 320/222 @ .600) Crane "Stroker Extreme" (228/236 @ .600/.600 on a 114), and Kooks 1 3/4" headers.

Here's what I hope for some advice on:
1.I've read here and elsewhere that the SLP 85mm MAF can be a tuning nightmare. What is the best solution for the airflow bottleneck of MAF and lid when you go up to the 90mm setup?

(In other words, with the 90mm TB and intake, aren't you leaving a good deal on the table with a standard aftermarket lid and, say, {what I have} a Granatelli MAF?)


2.The previous heads/cam combo made as much through the custom 3 1/2 Y-pipe with Random-tech cats and Corsa cat back as without the cats. Obviously I will move more air through the exhaust with 383ci than 346ci; does anyone want to guess just how badly I will need to lose the cats?

Thanks,
Tony

 

I'm going to keep my cats, but I'm also in California. I was wondering about this too. I think I'm going to go the SD/MAFless route. Hopefully by the time that I am done, the 90mm lid will be done. If not, I will probably conjure something up

 

The SLP 85mm MAF should be fine, dont want the Granatelli with a stroker. Also I went with TSP 85mm lid to help with flow. The more air in , you have more to move out. You have a good set of heads so you should be fine. I have the 90/90 set up with 85mm MAF and 85mm lid. They do fine! No bottleneck! Now for me, I have ET 245`s, they outflow my 90/90 pretty good. So I`m going in a differant direction with my intake issues. You car is going to run strong. Get ready! As for the cats. I got rid of them! But if you put a cut-out in. I would leave them for emission issues. Then just open the cut-out the rest of the time!

 

I would shoot for going Mafless and remove that resriction. In my particular setup (in sig), I only gained 2 RWHP over my MTI lid/Holley filter using a 90mm conical filter piped out to the the stock lid location (I'm on an SD Mafless tune as well). I imagine different setups will vary though especially with more cubes..

Dan

 

What are the trade-offs with speed density (ie. MAF-less) setups? Hardware investment? tunability (including simply finding an experienced SD tuner? Drivability (hp acrosss the curve vs. idle quality) etc?

FWIW, this is intended to be an non-daily-driver ORR type ride that sees weekend street time.

Thanks for the responses
Tony

 

I haven't had any ill effects from my SD tune, I don't think I even lost much in MPG. Idle is dead on. I have better throttle response too. As far as hardware goes, you just need a piece of 4" tubing/pipe to put in place of the MAF. Tunabilty is just that, finding a really good tuner. It would be best if you can get on a load bearing dyno and tune via a wideband. Guy that tuned mine has a dyno that can lock to any rpm and load it through the entire KPA range for that rpm which more simulates actual driving conditions under the most severe loading conditions.

Dan

 

I went mafless, no need for the restriction. My setup includes a set of AFR205's and running FLP headers with cut outs 12in behind the collectors. I also run a T-Rex which is heavy on the exhaust so it needs to breath. If it is a non daily driver car ditch the cats and go mafless.