Alright, all i want to know is what are the major differences between the hf and the si when it comes to engine swapping? I know the hf is lighter and only has rear brakes where as the si has 4 disc brakes and is much heavier. Both are mpfi as far as i know so, which one would you buy if you were going to swap in an engine?

 

I would buy an hf IF and only IF i were to swap in another engine because the car is light. Its prewired for mpfi incase u want to do a zc swap, although hubs will need to be swapped for SI/DX hubs to accept any other axles if using a non HF tranny

 

if your swapping of course get the lighter car but as he said your gonna need to get the knuckle off of a dx or si the splines are smaller on the hf!

 

I recommend the HF chassis if you can find a good one.

"althouth hubs will need to be swapped for SI/DX hubs to accept any other axles if using non HF tranny" -- This is incorrect. You do NOT have to swap out hubs/knuckles. You can reuse the HF (Std. same) axles for any D-series (- ZC) transmission as the inboard CV joints are all the SAME. Only the outboard joints vary. The difference between HF and Si/DX axles is not as grand as some may lead you to believe. Now if you plan to swap in B-Series etc, then yes, you'll need to change out axles and hub/knuckles.

The HF is already MPFI just like the Si so you'll be ready for any motor swap, excluding the addition of an OBD-1 Conversion, if you choose to do so. Be careful though, Injectors from the HF are different... 88-89 HF are only 192cc whereas 90-91 HF and all years of DX/Si are 240cc. I know from experience as I've owned an 89 CRX HF and have worked with a few other oddball HF's. The smaller capacity injectors will run a motor swap (even my JDM D15B VTEC) at idle but the moment you touch the throttle it will bog down because it's being choked to death.

"hf is lighter and only has rear brakes" -- I think you meant to say that it only has drums in the rear and disc in the front whereas the Si has 4 wheel disc brakes.

Good luck to ya! Feel free to ask me any questions directly.

 

91 si is the only one with rear disc brakes.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VegaS10 &raquo;</TD></TR><TR><TD CLASS="quote">91 si is the only one with rear disc brakes.</TD></TR></TABLE>
That is wrong!

To the OP: Picking between a Si and a Hf can sometimes be a hard decision. Si's do have some advantages like interior color, rear disc, bigger motor, interior options, sunroof, better seats, rear sway bar, better transmission, etc, etc....The Hf only has one big advantage, and thats the wieght.

Its really all down to what you are wanting to do to the car. If its a DD then Si's do have some nice extra options. But if your car is just a weekend car to play around with then the Hf would save you some work on trying to cut down wieght.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VegaS10 &raquo;</TD></TR><TR><TD CLASS="quote">91 si is the only one with rear disc brakes.</TD></TR></TABLE>
NO

90 and 91

 

I like the si's. The brakes, sunroof, and seats are ballin.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ILcrxsi1 &raquo;</TD></TR><TR><TD CLASS="quote">I like the si's. The brakes, sunroof, and seats are ballin.</TD></TR></TABLE>
x2, I would like to get an HF now though since I have a complete Si (smashed rear 1/4 panel ) I could use to swap in all the good stuff while still keeping weight down

 

You could always get rid of weight for free. But getting all the extras a Si has costs.

 

IMO i would stick with an Si over the HF. Has a lot better features like tilt steering wheel and better color interior. the sunroof on the si can be a neg or pos i personally like it in the summer especially since i have no A/C, lol. But is a neg because sometimes there non functional (mine works well) and they provide less head room. the headliner is lower on an si because of the sunroof. i fixed the problem by getting fixed low seat brackets for my recaros so i can fit with a helmet. just my .02

 

I like the Si better because it has a front and rear sway bars..alloys...and a better engine from stock. The HF is great but if you add all the stuff that makes the Si better the HF will wiegh more than it started out *** but will still weigh about 50ish pounds less since it wouldnt have a rear wiper or sunroof. I like both HF and Si because I dont roll with a stock d series for long anyhow

 

i'm all about the si sunroof

 

I own both and i'd drive my Si over the HF 11 days out of 10. Unless you're building a race car, that extra weight translates into things that make the car more comfortable to drive and an overall better car.

 

I wish I never sold my si rex like many said the sunroof and pimp *** seats

 

Unless your building a weekend warrior and want the CRX to be light as possible, I'd go with the Si model. Things like the sunroof, interior, rear sway mounts, and the original power plant/tranny are a much better foundation to build on. + you can always subtract weight from the Si. My 91 probly only weighs like 1900-2000 lbs.

Personally, I'd want an 88 Si, because your getting the best of both worlds -rear disc.

 

I would say get an SI right out of the bag you get a powerful little motor boost friendly. But if you want a bad *** track car get an HF

 

I would get whatever one has less rust.

 

^^lol good point ^^ its not like these cars are easy to get in good shape