Rapido!

XR4Ti / Sierra / Sierra Cosworth Discussions - Questions, problem resolution, general talk, technical tips and modifications.
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noslack2mack
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Rapido!

Post by noslack2mack »

Is the Rapido IC a good performer? I want to keep the AC. Soooo.....open to suggestions. :D
Ronald Reagan was the best thing that ever happened to this country.

-Mike
JimG
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Post by JimG »

Originally the Rapido I/C was the only game in town, then MP made one similar but using a large, long I/C that installed laying down near the bottom of the radiator. I don't know how well either performed but never liked either installation feeling that the pipes were too long.

I'm not striving for drag car type performance just a fun to drive street performance car but I've always liked the Cosworth or RS500 top mount idea. Therefore I went with a shorty aluminum radiator for Merkur Depot with the I/C mounted above and a Forge BOV and a manual (Gillis valve) boost controller. This enables me to keep the A/C and the I am happy with the performance and the radiator keeps the car running cool.

You can see some pics of the radiator at their website www.merkur.50megs.com. You can find some pics of other installations in the Project, Video and Photo forum.

I'm sure others can share more scientific information on this subject in this forum but also check out www.turboford.com
Jim Gosses
86 XR4TI, 165K, T-5, IC, RR, PBR Fronts, T-bird Rear Discs
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C-Rock
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Really only option

Post by C-Rock »

Mikes Set up is really the best set up for this. I have it now but removed the AC and have the boost at 17 lbs with the blow off valve. It works real well and is not all that expensive. Doing the rotated intake is also the best way to go and you can do this with the right rotated intake. Having the long pipes is just not the best way to go.

C-Rock
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Post by MerkXRTurbo »

The Rapido is a good core, MP is a great core, but as an entire setup they both leave something to be desired. The problem with the Rapido setup is that the piping is so small, and the BPV/BOV port is only 3/4". Length of pipe in an intercooling system has been shown to have negligible effect on performance.

If you're a guy that wants a little more oomph, but wants to keep the car basically stock otherwise, and you can get a Rapido intercooler for a good deal then I'd say go for it. If you're looking to build for big power, then I'd say to keep looking.
3" mandrel bent exhaust, Ported/Polished head, 1.89/1.57 valves, Gutted uppper/Knife edge lower intake, T3/T4, LA3, Big VAM, Cold air intake, 40bob header, Gillis valve, Forge BOV, Mustang SVO T5, Conquest intercooler, 20psi.
noslack2mack
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Post by noslack2mack »

Thanks for the wisdom! Maybe 225-240 horse? Seems achievable enough without going gonzo. I guess I can do the LA3/VAM/intercooler thing. Replace the downpipe. It has Magna exhaust on it already. Would a 65mm TB improve anything on something that is so mildly done up? And it'll probably need some porting of the upper end, just to help it breathe. I guess when the hammer falls and that turbo kicks, it should be like "wow! this little car has the goods!" You know - deceptively "not factory".
Ronald Reagan was the best thing that ever happened to this country.

-Mike
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Post by hEaT »

65mm TB won't help at all until you are making BIG power.
noslack2mack
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Post by noslack2mack »

Thought so.
Ronald Reagan was the best thing that ever happened to this country.

-Mike
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whitelx
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Post by whitelx »

noslack2mack wrote:Thanks for the wisdom! Maybe 225-240 horse? Seems achievable enough without going gonzo. I guess I can do the LA3/VAM/intercooler thing. Replace the downpipe. It has Magna exhaust on it already. Would a 65mm TB improve anything on something that is so mildly done up? And it'll probably need some porting of the upper end, just to help it breathe. I guess when the hammer falls and that turbo kicks, it should be like "wow! this little car has the goods!" You know - deceptively "not factory".
The rapido intercooler is pretty much done about the same time as the T3 turbo. I made 256rwhp with my Rapido intercooler. At 225-240 hp it would do just fine.
1986 XR4Ti - 294rwhp/315ft-lbs
1992 Mustang 5.0 notch - 434rwhp/445ft-lbs
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