OK, now I'm totally lost - HELP!

**straightliner1** · 07-26-2005, 03:28 PM

I'm currently having a 348 short stroke built and intended on strapping on a T trim with some form of intercooling on the nose of the car - be it air-to-air, or Vortech's aftercooler. After speaking with AFM, they recommended I stick with the smaller S trim since this is a street oriented car and ditch any form of cooling the charge due to boost drop.

I had intended on running about 10 PSI through the T trim on the street but crank it up to whatever the tune will allow with a tank full of 100 octane. Am I foolish for holding out for the T trim on my 91 streeter, or should I enjoy the S trim?

**BLOWNBY** · 07-26-2005, 09:20 PM

If you already have the s-trim then I'd just keep it for now. Use it till you max it out. My s-trim (pretty much at max rpm's) on my 351 made 13psi and 530 at the tire. It was tuned on 110. Then I could run 93 or mix 110/93 on the street with the BTM @ 3. Then switch over to the T. I doubt you have much better results with the T if your only making 10 psi. When you want to turn up the boost then get the T.

As for the cooler I'd holf off as well. Again at 10psi the cooler really isn't needed. It may allow you to run a few more degrees of timing, but hold off for now. I knowmy tuner (Lidio at Alternative Auto) doesn't really like the idea of a cooler on the fox bodies for a street car as well.

**straightliner1** · 07-26-2005, 10:20 PM

Blownby,

The car is currently being built, or should I say rebuilt from the ground up. The engine is at the shop, I haven't purchased any blower yet, I still need to plumb my brakes and install all the wiring back in the car! Holy sh1t I have a long road to hoe! ;)

I was looking at the boost maps on Vortech's site and it looks like the T will fit the bill a bit better with the larger "sweet spot" in the power curve, as well as leave me room to grow should I need to upgrade at a later time. - (LOL) I'm just a bit worried about getting greedy with boost once I get the car running and without any form of constant intake charge cooling I feel like I'm asking for trouble.

Long story short, I have always seen/heard intercooling helped with cooling compressed intake charges. Now I'm being told they suck due to boost pressure loss. Couldn't I just compensate for the loss by pulleying the blower appropriately?

**regattacoupe** · 07-27-2005, 12:22 AM

Originally Posted by straightliner1

Blownby,

The car is currently being built, or should I say rebuilt from the ground up. The engine is at the shop, I haven't purchased any blower yet, I still need to plumb my brakes and install all the wiring back in the car! Holy sh1t I have a long road to hoe! ;)

I was looking at the boost maps on Vortech's site and it looks like the T will fit the bill a bit better with the larger "sweet spot" in the power curve, as well as leave me room to grow should I need to upgrade at a later time. - (LOL) I'm just a bit worried about getting greedy with boost once I get the car running and without any form of constant intake charge cooling I feel like I'm asking for trouble.

Long story short, I have always seen/heard intercooling helped with cooling compressed intake charges. Now I'm being told they suck due to boost pressure loss. Couldn't I just compensate for the loss by pulleying the blower appropriately?

Honestly the benefit of cooling are nice but nothing compares to having 112-116 octane in the tank and running aggressive timing. I'm not talking about mixing either cause that's for the birds. Is it expensive? Yes and no......$1000 intercooler setup buys lots of race fuel and if your gonna make big power you're gonna end up running it anyway. The price per gallon is scary at first, but when you factor in hp gained, and ruling out detonation(within reason) it's pretty darn cheap.

**straightliner1** · 07-27-2005, 08:34 AM

Well, since this will be the weekend driver and being stuckin in the republic of Kalifornia I am stuck running full smog equip so getting the upteenth last HP isn't of true concern. However I do want to maximize my combo for the street and still be able to pull up to the pump at 76 or Chevron and fill er up with high quality premium unleaded and enjoy the car. If I feel like dropping the blower pulley down a couple teeth and filling up with some 100 unleaded to crank up the wick I still want the option. Am I being unreasonable?

**regattacoupe** · 07-27-2005, 08:58 AM

Ahh I see. Either way it sounds like you'll need a custom tune to get it on the road in Cali. I certainly don't think you're unreasonable at all. If you get a solid pump gas tune, add straight 100 octane and some timing, it's the next best thing to a pulley change on a blower car.

**straightliner1** · 07-27-2005, 02:34 PM

Excellent! So this brings me to my next question; does anyone sell a "tuner kit" with just the head unit and minimal accessories so I can do my own fabrication and add an air-to-air intercooler?

T trim here I come! :)

**BLOWNBY** · 07-28-2005, 08:38 AM

Yeah, I'd get the T, plus leaves plenty of room to grow then.

**straightliner1** · 07-28-2005, 02:57 PM

BLownby,

I just noticed something:

Yet another change---> YSi sold: aftercooled T-trim on it's way!

Can't take atrimterror/90cobrakiller's or regattacoupe's smack any more!!

Why are you "stepping down" in size? Is the cooler gonna make up for it?

**BLOWNBY** · 07-28-2005, 07:45 PM

I think the YSi was too big for my setup. Granted it made 670+ RWHP AND 20 PSI. I think now that the t trim will make the same top end yet a bunch more mid and low end. Now it may be due to my came or whatever, but I will now hopefully mid next week. I have the system just need to finalize some stuff with the bypass.

Not sure what the cooler will do. But I plan on 20+ psi again. I run c-14 at the track so maybe I can throw a degree or two at it with the cooler now or lower my BTM? Have to see.

**tomcat** · 08-05-2005, 05:37 PM

Long story short, I have always seen/heard intercooling helped with cooling compressed intake charges. Now I'm being told they suck due to boost pressure loss. Couldn't I just compensate for the loss by pulleying the blower appropriately?

If an intercooler setup is restrictive you won't gain much unless you spin the blower faster. That means you are heating the air more to begin with and drawing more power off the crank to turn the blower. I can see some tuners saying it isn't worth it and just running race gas. But what if you could add an intercooler without adding restriction to air flow? It is possible with a well designed air/water intercooler setup.

I'm new to this forum so I don't expect anyone to take my word for it. So I'll supply some facts and figures to back up this statement.

In one of our first tests we found the following on a Superflow 600 bench. All readings are @ 28" H2O.

750 Holley - 1000 CFM
Same carb inside a Vortech carb box with blower discharge pipe and two 90 degree elbows - 645 CFM
Add the intercooler to the discharge pipe using two transitions - 545 CFM

We never think about how much additional restriction is added by the discharge piping and an intercooler, and it can be much worse than this example. After seeing these results we developed an integrated carb box/intercooler for marine engines and eliminated almost all the piping, elbows and transitions. The result was 750 CFM on the flowbench, better than the original carb box alone. What this means is that the improved intercooler would work better than the original carb box alone, even if there was no water running through it.

We followed up the flowbench work with dyno work. The before intercooler setup made 650 HP on a 454 marine engine. The improved intercooler added 2 psi boost and made 740 HP without changing the blower pulley. Even without water running through it the improved intercooler made 717 HP. Further testing in a boat showed speed increases as expected, but even more interesting to us, intake air temperatures at WOT dropped from 115F to 90F at the same time that boost increased. Sounds backwards doesn't it?

So don't always accept the conventional wisdom about intercoolers. To get back to the original question, S or T trim, I say T because with an improved intercooler setup the whole engine is going to flow more air.

**straightliner1** · 08-05-2005, 09:49 PM

I've already decide on a T, due to the boost map. The sweet spot looks a little larger. :)

...still scratching my head on the intercooler setup. Intercooling makes sense in my head especially since I am not going to run racegas on the street - LOL.