Ported oem heads vs aftermarket heads
 

Hey guys.

I’m looking to spice up my 6mt 21’ 1LE. I know whp is just a number but I’m looking to get to 550 plus a 100 shot. I plan to do full bolt ons and heads/cam and tune. Will ported oem heads get me there? We don’t have E85 up here in Canada but I can get 94 octane from the pump. Thanks guys

If you're going ported OEM heads, I would talk to PRAY performance about porting. Currently FBO E85 + cam @ 530 whp, adding ported manifold, mast heads, and pistons/rods. Hoping for 550+

I have CID heads with my n/a setup. I’m over 600whp with an msd manifold. Stock ported heads will get you where you need to be. Hit up Zack or James at GPI and let them know what you’re looking to do.

if you want to go the ported oem route, pray performance hands down is the place to go. Some of his factory ported heads put big dog LS7 heads to shame. I believe his top two OEM ported heads flow 400+ CFM, which is just straight up ridiculous.

LT1 heads have some valves issues that seem to show up when you increase spring pressure, cam lobe intensity, and RPM. I believe Pray is around 4500.00 for a fully reworked set of ported OEM castings(New valve seats, valves, valve job, porting, springs...etc). However once he is done with them they seem to perform as good if not better then aftermarket stuff and even LS7 stuff as Dan mentioned.

I am not saying you can't get away with a port and valve job with new springs and hardware. Going that route is probably ok on something mild staying under 7k rpm. But if you are considering a more aggressive H/C setup with Nitrous on top it might be something to consider. Contact GPI or Pray and tell them what you are looking to do.

Stock bottom end?

Gpi piston/rod.

Mod list?

Nevermind, I found it! Is the ATI dampener worth it?

It is worth it if your goal is all the available naturally aspirated power, Kind of a hidden nook in the cranny. I feel like it adds around +10 rwhp with EVERY other NA supporting mod.

It depends on what you’re willing to spend to free up those last few ponies. I’m debating whether I should go hi ram now but I really don’t wanna cut up the car.

Hi ram is the intake Pray's cars make the top numbers, I too ain't cutting my hood though. Ported MSD is the next step down.

yeah that's my main issue, cutting the hood. I'm not too fond of losing more visibility with a copo hood, plus at the end of the day its going to cost more than my ported MSD

How much compression is everyone getting with the stock heads? TSP milled mine .030 but they said thats as much as they would go and wouldn't go any further. I run full time E85 and I want to be able to take advantage of it and get my compression up to around 14 or maybe 14.5.

I think the vfn looks a lot better than the COPO and you don't lose quite as much visibility since the cowl isn't as wide.