OEM 7MGTE Intercooler VS Aftermarket FMIC

[LPC]

Hi guys, Have had a bit of a search but can not really find anything. I was just wondering at what powers or PSI does the stock FMIC reaches its efficiency, and by upgrading to an aftermarket cooler what type of power gains can be expected ?Your help and imput and is much appreciated. Thanks, Jon

 

[Nick M]

The factory intercooler leaves little to be desired with regards to both pressure drop and cooling effectiveness. When we ran our first dyno tests on the Supra (TURBO Jan '87) we thought the restriction at higher boost pressures was actually in the turbo, but in conferring with Cartech, Spearco and HKS it was found that the stock intercooler itself was a major contributor to the problem. Testing at Cartech showed the stock intercooler to have a 3 psi pressure drop a 6.8 psi and a whopping 4.3 psi pressure drop at 9 psi. In other words, the turbo had to do the same work and therefore, produce heat as if it was run at 13.3 pounds of boost, while the engine itself was only seeing 9 pounds of boost.


All of these intercoolers are similar in size except that the Spearco unit also employs slightly larger diameter tubing in some locations going to and from the intercooler.


The only intercooler we were able do to an actual before and after test with on our own car was one of the units from Cartech. At stock boost pressure we found an 11-horsepower gain between the stock and Cartech intercooler. While this gain was actually measured at the stock (8 psi w/exhaust) boost pressure, it should be noted that intercooler efficiencies are best tested in a real world or street environment with actual air flow across the core. Previous testing on the Cartech intercooler showed a 7/10 psi drop at 6.8 psi and 1.10 psi at 14 psi which basically agreed with our dyno runs. In addition to actual pressure drop, Cartech testing of the intercooler showed 89% efficiency vs. 68% on the factory unit. With the similarity in intercooler upgrades, it would be safe to say that any one of these would be an almost mandatory option if you are starting to go for serious boost.

HKS claims 78% efficiency and 1.5 psi pressure drop at 15 psi for their intercooler, similar to the numbers for the Cartech unit.

 

[LPC]

Thanks Nick, will be going shopping later this afternoon

 

[dubsupra209]

damn ive been told stock ics good for 400hps...?

 

[89supra7mgte]

i did the driftmotion kit, on stock boost i increased 50hp. upped the pressure to 15psi and put down 355hp 403 tq

 

[MKIIINA]

The stocker can flow alot but it's not as efficient as an aftermarket cooler

 

[Nick M]

i did the driftmotion kit, on stock boost i increased 50hp. upped the pressure to 15psi and put down 355hp 403 tq

You increased the boost with a controller? I know you aren't saying the intercooler restriction raised pressure (because pressures is resistance to flow) and increased 50 hp.

The stock unit besides being not as good as a Spearco core in terms of flow, heat soaks quickly. Sure it can make 400. But not repeatedly.

 

[89supra7mgte]

the stock 7m i think is 237hp after my upgrade i had it dynoed before tuning. i pulled 277hp and 280tq at the wheels on 7psi, then upped the boost to 15 and pulled some fuel out, and got 355/403

 

[I6Boost]

the stock 7m i think is 237hp after my upgrade i had it dynoed before tuning. i pulled 277hp and 280tq at the wheels on 7psi, then upped the boost to 15 and pulled some fuel out, and got 355/403

Thats kinda hard to believe.

How do you know it didn't already do 270-277 on the dyno?

The 7M can be completely stock and if you just have the head ported/polished, Oil system shimmed,
ct26 shimmed, and maintained very well its not a problem at all to pull 300hp with nothing aftermarket.

 

[89supra7mgte]

well i guess your right. That was the first dyno since i had the car. was going off stock numbers, or what as listed as specs for that engine. I do know there were no shims, no port and polish prior. And i highly doubt that engine was 270 prior. Correct me if i am wrong but you lose hp due to elevation correct? Say from sea level to 6600 feet? I dont know how much change you would have due to changes in air, but if it was 270 or so before i would not have invested as much as i did into it would have done the shimming and what not.

 

[Nick M]

Yes on elevation. A stock turbo just doesn't build a lot of cylilnder pressure compared to stock at elevation. Where in Colorado?

 

[89supra7mgte]

Colorado springs. I honest to god just found out my firing order is effed also only 1 and 6 are in the correct location? unless someone was messing with me thats how i ran it on the dyno and since i owned it? Car ran great too?

 

[Poodles]

Yes on elevation. A stock turbo just doesn't build a lot of cylilnder pressure compared to stock at elevation. Where in Colorado?

That's why turbos rock, they have the same power regardless of elevation (thought there may be lag).

 

[Nick M]

That's why turbos rock, they have the same power regardless of elevation (thought there may be lag).

He is in the Springs, but the track is in Denver (foothills) at a little lower elevation. And the turbo does fall short. Maybe an electronic controller will help, but the car does suffer at elevation. I promise.

On a side note, I ran my old 5.0 at Club clash on Fridays 10-15 years ago. Grudge matches and such. It was a lot of fun, even though all the cars are slow.

As for the intercooler, you can see how good an upgrade is with the articles above. There is another on the SuprSonic page. He put the HKS setup on his CelicaSupra. Sweet ride.

As you can see the stock pipes were very twisted up. This setup producted a max 348 HP & 400 Ft/lbs torque at the rear wheel on my Supra GTE. Not bad for a stock system....

And with the HKS unit

The SONIC Supra GTE 365 RWHP 7M-GTE powered 1982 Supra

Not bad for 14.5 lbs of boost. So as long as you have a good unit whether it is the HKS unit, Cartech, or anything with a Spearco core and good pipes, you will benifit from it.

 

[Poodles]

Wastegate is activated by pressure, as long as there is air the turbo will work to hit that pressure. It's why minor BPU 7MGTE's can beat the snot out of vipers at elevation as they're not as effected by the elevation.

Keep in mind most of the benefit is going to be from replacing the old leaking pipes. It's also not the most cost effective upgrade if you're buying one of the name brand kits new (like the HKS).

 

[suprarx7nut]

Wastegate is activated by pressure, as long as there is air the turbo will work to hit that pressure. It's why minor BPU 7MGTE's can beat the snot out of vipers at elevation as they're not as effected by the elevation.

Keep in mind most of the benefit is going to be from replacing the old leaking pipes. It's also not the most cost effective upgrade if you're buying one of the name brand kits new (like the HKS).

Poodles, you dont get the same pressure at elevation. Correct me if I'm wrong, but here's why (As far as I know)

The wastegate opens at a certain pressure from the inside, but that spring pressure totally depends on the pressures on both sides of the wastegate. Up here in Colorado, the pressure on the outside of the wastegate is ~20% lower than what it is down there. Therefore, the spring will feel pressure pushing it open at 20% lower pressure.

If you were in an environment with a 20psi atmospheric pressure, the wastegate would not be budged until over 20 psi. The spring dictates that there is a given DIFFERENCE in pressure. It does not ensure that there is a given pressure inside the motor.

In simple terms, the wastegate controls psia, NOT psig.

Maybe I'm wrong, but that's what my physics education and my admittedly lacking knowledge of turbo systems tells me.


***Additionally, it is harder to build pressure up here because the air is substantially thinner. The stock turbo has to work harder (maybe ~20%) to hit 10 psi here than hitting 10 psi in Florida or sea-level Texas.

 

[Nick M]

Turbos do not run stock power without help. And then it isn't stock. I guess you have to see a stock GN run a 16.0 before you believe it.