86redIROC

Some im trying to decide how to upgrade my Trick flow 175cc heads. Total Engine Airflow has a CNC program for them that takes them to 205cc with 2.02/1.60 valves and the flow a whopping 290cfm. Right now im concerned that is a bit much for my Edelbrock TPI base and AS&M large tube runners. I think to take advantage of those heads I would need to go to an HSR or First TPI intake. Also ideally I think i would need a bigger cam than the comp 12-268-4 that I have to take advantage of that much airflow. 12-367-4 looks like a good cam for that size of a head. just trying to keep the build matched as much as possible with the proper parts. Thoughts?

Orr89RocZ

iTrader: (20)

What do you want the car to do? A 205 head and cam with matching intake can be a mid 11's car. 400-450 whp. How hot you want this motor?

Your tpi base would need alot of work to really feed that combo. Same with the runners. It can be done but not easy

86redIROC

Would like to run about a 12 flat with about 400rwhp. I was looking at the First manifolds and they definitely flow the cfm (300ish) but im concerned that they wont pull much past 5-5500 rpm due to runner length (i have 3.73 gears) I think and HSR would be the way to go with upgrading the heads and cam allowing me to shift around 6-6200 rpm.

Orr89RocZ

iTrader: (20)

How good is the motor bottom end? 6200 will get you low 12.0 with either intake imo. Et is function of how well car works at track and how light. I tuned an 86 that did 12.2 with just 330 whp. My 89 went 11.4 with 392whp heatsoaked. Both hsr cars. Both around 3400-3450 lbs. First will hold power to 6000 if you cam it up. Dont be afraid

86redIROC

New Blueprint engines 355 shortblock, has about 1200 miles on it now. Do you think the 280XFI flat tappet will crutch the First intake up to 6k? I like the idea of the First more than the HSR (it fits under my strut tower brace, and should keep low end torque up with those 205cc runners) I just didnt think it would let me shift high enough with the 3.73's?

Orr89RocZ

iTrader: (20)

That cam will work but is pretty big. I wouldnt go much smaller tho. The roller version does a good job in a 355 to 6500 rpm

How does it do with the current 268 cam?

86redIROC

Have not Run it at the track yet but the 268 pulls strong up till 4500 then flat lines till 5500 due to the TPI runners etc. Feels like it would run a low 13 (seat of the pants guess). Going to dyno the current combo at Smokeys Dyno and Performance in Akron in a couple weeks. Will get some further tuning done while there also. Maybe I should do the heads and First intake and leave the 268 and see if that meets my goals?

Orr89RocZ

iTrader: (20)

Always nice to change one thing at a time. Verify the current power curve with the 175 heads and intake and cam. Keep an eye on how far past peak hp rpm the power hangs on to. You can then decide on first tpi with ported heads and see where the 268 gets you. It should make more power and give alittle more rpm range to play with. From there if its not enough, simple cam swap.

Granted its more work and time but atleast you did the bare minimum parts buying and swapping to get your goal. A methodical approach. Look for good power then focus on getting that to the ground at the track. ET will come.

I also can see just doing heads cam intake all at once and be done with it. Lol it should make the power you need to get deep into those 12's, depending on weight and rest of car setup. I am assuming a fairly efficient drag setup thats at typical 3400-3500 lb race weights

Last you could do ported base and custom siamesed runners based on your as&m ones. Before doing first tpi. Need to have a welder fill the space between runners with weld to allow you to port the inside back, siamesing a good 2-3". Should net another 500 rpm of usable power range, plus more power period

86redIROC

I see the Socal guys do the heavy modded SLP's but not sure how to do that as easy with the AS&M runners. By the time I had someone do that its seems the costs would start creeping toward the First intake. Also, I believe the total runner length is two inches shorter on the First which in itself would be good for a few hundred RPM's.

Orr89RocZ

iTrader: (20)

True cost would add up alot for a modded base and runner like the cali guys run but shows potential of the design

First will already feature the larger base and runner at a price thats not too much more than typical aftermarket new tpi parts as is, let alone one that is welded up and ported larger. First is a good bang for the buck. I think it will do well.