I ported & siamesed my SLP runners 2 ½ “ on both sides and I also ported & siamesed my Edlebrock Hi-Flo intake 2 ½” . So total porting& siamesing equals to 7 ½ “. I got a 52mm TB and my plenum is also ported and siamesed. All items are gasket matched. All this is going on top of a ZZ4 short block w/AFR 190s and an LT4 hot cam.
I’m thinking that I should be able to make power up to 5800-6000 rpm, at the very least. I’m I wrong in my educated guess?
I’ve been reading a lot of posts about some of you guys making these mods and it inspired me to order up a set of carbide grinding bits and go to “crazy”(in a matter of speaking).
If anyone has any suggestions, as to what kinds of RPMs I should expect, I’d greatly appreciated.
I mostly need this guess-timate so I can give more or less decent specs to have a chip burned.
Thanks in advance.

 

You'll have a larger TB (mine was 48mm), but that shouldn't affect max RPM. I can only guess that porting the intake deeper will gain you a few RPM. 1 3/4" primaries on the exaust will help, too. My guess is you'll max out around 5500.

 

Well, if you're planning to have a chip burned for you, expect to run a lot slower than that combo's potential. There is no way someone can burn you a chip that will be remotely close to correct unless they have your car in their hands.

Rather than waste a single penny on someone else's chip, you're much better off learrning to do it yourself. It may seem like a lot to learn, but once you do get the hang out of, the results will be MUCH better. AND you'll have the satisfaction of knowing that you tuned the car.

If you absolutely must buy a chip, Ed Wright @ fastchips seems to do the best work for an off the shelf custom chip. His first pass probably won'tbe perfect, but from what i've heard he'll retune it based on scan tool data if you send it back to him. Of course, a chip from him is going to cost you way more than just learning to do it yourself.

As for anybody elses chips, forget about it. From collective experience, noone else seems to make a 'custom' chip that has anything custom about it. For example, before Trax got into prom burning he was running a TPIS stage 4 or 5 chip with a very similar combo. When he finally got into PROM burning he looked ta the TPIS chip and found STOCK fuel tables. Now, do you think AFR 190s and a healthy cam are going to run remotely correct on stock fuel values? Exactly, and it didn't. There went $500 down the drain. Performance resource chips are the same way, most of the people i've seen that shell out the money for their 'custom' chips end up slowing down compared to stock.

 

I had the SLP runners on my car and they would not pull above 5500RPM's. This was a built 350. I installed a Super Ram and it pulls to 6000RPM's. Picked up 1.0 just by getting more air in.

RCR how you been? I have not seen you since dyno day. Are you going to be at the Woodward lot with Motown Muscle? If so I will see you there.

 

How deep can I port the intake?
Could I do it all the way or just a bit?

 

I feel the problem is the plemun and runners. They just will not flow enough air into the intake. No matter how big the heads and cam the air has to sqeeze thur the other areas. If you want to wake up the engine get a super ram box lid and runners. 3rd gear will pull like second and 4th like 3rd. hopes this helps.