LetsGO7

iTrader: (2)

Hey list,

What are your opinion on intercooler core sizing (for the FD)! Ok the car will be running stock engine (with stronger apex seals, no porting) and stock twins. Trying to get around 400 or over (if possible) but how big do i go? I am thinking about going core size 16~17length and 10~12 width and 4.5 thichness (3-row). looking to shoot around 0.9~1.1bar. Is this too much for the stock twins? What kind of drving? not a daily driver.

thanks

-joe

LetsGO7

iTrader: (2)

come on, anybody?

cartervs

As i understand it, you have answered your own question. The 3 row has been to much volume for several FD3s owners to use with twins. Carter

cartervs

As a note. Jason at the RX7 Store has a good IC on special for only $899.00 Great for twins! Best of luck, Carter

LetsGO7

iTrader: (2)

what is the "core" size of the m2 and greddy front mount intercooler? (LxHxW) thanks

-joe

cartervs

As you apparently aware of a terrific site tio do your homework at go to WWW.Scuderiaciriani.com and you find a wealth fo info to bring you up to speed and informed. I have (and still do) spend hours there. Keepe'm Spinning....Carter

bkapold@aol.com

Wow! lots of help these guys are

My friend Kevin Wyum was the designer of the "M2" IC's....The ASP IC's are the samething FYI.....

The medium IC is perfect for your combo, the large unit is good too but you'll have to relocate the battery and a couple of other minor things......

I can't remember the dimentions, but I'll contact Kevin and ask him.... I bought my Spearco from him too, but I have a 91 Turbo II.....If you want stock location for simplicity stick with the ASP IC/ M2...... If you want to FM the IC I bought a 27" x 7.5" x 3.5"....I think most people go to tall and its messes with our water temps....

Let me know if you want those dimentions......Kick this around, in 95 Kevin "ASP" Wyum ran a 10.89 on the stock motor, non-seq. twins, large ASP IC ran by a Motec and 2 additional injectors...the guy was light years ahead of most on this site......


Brad

LetsGO7

iTrader: (2)

hey cartervs,

thanks, alot of info!! oh and bkapold, i sent you a pm, please answer.

thanks

-joe

88IntegraLS

^

Anyone have any more comments on sizing an intercooler for a given power goal? How would I know if I am considering an intercooler that might be larger than optimum? Anyone?

Evil Aviator

What do you mean by "optimum", and what is your concern with sizing?

RETed

Use the biggest thing you can afford and fit up front.
Make sure you don't run into overheating problems due to the front mount.

You turbo has problems producing boost.


-Ted

88IntegraLS

Lol, it will be for a lysholm supercharger and the power goal is 300 crank hp, so it will have no trouble spooling, but I'm concerned about volume between the compressor and ports, and flow restriction. I haven't been able to find flow rate vs. cooling efficiency for given charge temp and cfm, so was just wondering what the rule of thumb is . .

Like for example, would something with a tube / fin core in 20x8x3 be too big for 300hp since it will "support" twice that, according to the ebay sellers? The stock intercoolers on the Millenia S (where my compressor came from) are just tiny compared to a typical ebay fmic . .

88IntegraLS

Oh well, I'll just estimate the optimum size and report back with results . . a little empirical data collection . .

Evil Aviator

The trouble producing boost as listed by RETed is related to the volume between the compressor and ports, not spooling. The more volume there is for the supercharger to pressurize between shifts, the more difficulty there will be with rapidly pressurizing that volume. This results in lag, yes, even in supercharged cars.

The Spearco (Turbonetics) catalog has intercooler maps. There isn't a rule of thumb because intercooler construction varies. Not only do different brands have different construction, but also the same brand may use different construction methods for certain types or sizes of intercoolers.

There is not necessarily a correlation between the physical size of an automotive intercooler and its ability to support a given amount of horsepower. For example, if I have an engine that is 500 peak hp NA, and I boost it to 520 peak hp under boost, then how much of an intercooler requirement would I really have? Not much. Yet I could sell the intercooler on Ebay as a "520hp" intercooler. Try using that intercooler on your 160hp engine boosted to 300hp, and you may have problems.

Basically, you are looking for 2 things for performance:
1) Thermal Efficiency ( (T2-T3) / (T2-T1) ) at a given engine airflow rate and intercooler airflow rate.
2) Pressure Drop (P2-P3) at a given engine airflow rate and boost pressure ratio.

Other factors:
1) Internal volume (lag)
2) Fitting - must fit in car
3) Airflow through core
4) Airflow through radiator

Now if all that is too troublesome, there is always the ghetto rule of thumb: "Use the biggest thing you can afford and fit up front."

88IntegraLS

Thanks, well said.

SPOautos

Well, if your flowing 500 cubic feet of air a minute which is 8.33 cufic feet of air persecond I dont think using a larger IC is really going to make that much difference. Especially when comparing 2 fmic or 2 smic cause all the piping would be the same. Now if you compare smic to fmic then you add a little more with the pipes, but honestly on a street car I dont think its really going to matter. Get the biggest you can afford and fit because on day your going to be getting a single, you might as well plan for it now so you dont just waste your money by buying another IC down the road.