Hey all,

Looking to make some mods to my 82 crossfire. Considering boring +.030 and adding a 3.75 crank with 6 in connecting rods (383). Is this achievable, and will anything be required as far as the computer or fuel goes. Considering a scat stroker package to ensure reliability and function between each of the parts.

A lot of reading in this forum and some have suggested upgrading the cams with heads and either boring the manifold or converting to carb. I like the nostalgia of the original crossfire, not sure how tuning/adjusting it for max efficiency and performance is done. If others have gone with the carb conversion, which manifold and carb did you chose, and where there any problems with the hood?

I understand there will be transmission and rear-end considerations to make, but is the boring and crank/rods increase a realistic mod?

 

I have no direct L83 / crossfire injection experience.

Everything reliable I've read or heard tells me the Xfire induction is a serious chokepoint restricting more performance.

That it take lots of money, parts and/or modifications to get (compared to other induction systems) even a modest performance return.

The motor itself is a fine candidate for creating a 383 etc ... but Xfire will limit how that improves your experience.

In recent years, several popular aftermarket FI systems have emerged as reliable, not too difficult to set up, and affordable.

 

Building a CF is simple just like any other SBC, the trick is in the intake up and the ECM. You are building or wanting to build a standard 383 motor with 6" rods. There are lots of members with lots of ideas on how to go about that. At the end of the day, how DEEP are your pockets? If it were me even for a stout street motor, I would go with forged everything so you don't have to worry about the lower end for any reason. That includes crank, rods and pistons. The cam of choice would be a roller with a good set of roller rockers. Don't skimp on the push rods either, get a good set with at least .080" wall.

Since your dealing with a CF second gen ECM on a somewhat big motor, you will have to upgrade the ECM to either a GM 1227747 or 1228746 and I strongly suggest that you go with the EBL FLASH II from Dynamic EFI and then there's the tuning. Also, strongly suggest going with TunerPro R/T for that. You may be asking why those two items? First off, you can use something else like a Haltec system which would be the ultimate way to go and I almost went that route myself, but I would have to learn yet another system which I'm really not into that right now. The other two options I mentioned will work great for you and you can go to a forum called ThirdGen and find TONS of info on both systems and plenty of good guys to help you out there including the owner of D/EFI who sells the EBL FLASH system.

You will also need to upgrade your TBs to 2" at minimum, run an external FPR from Aeromotive which works great, Setup a parallel fueling system, HAM board and injectors to a minimum of 80# and then boost the FP up to 20-22psi which is approximately 195pph total on the injectors @22psi. If you are new to laptop tuning, there is a rather steep learning curve with TunerPro just like any other tuning software, but you can learn it somewhat quickly, ask a lot of questions on Thirdgen. The cam you select can be rather large if you like, but keep in mind that you need vacuum for the brakes and headlights, so that is somewhat a factor. My latest cam is .612, 228-236, 112 which isn't huge, but larger than my last one and hauls *** in my 383. The heads I used before were Dart Pro1 and now AFR 195.

Trans... you can still use your 700R4, but you might want to go through it and do a few mods like a 30 spline input shaft vs the stock 27 spline. Update the SUN shell and go to the wider band, rework the gov for the shift points and upgrade the clutch pack. I would also upgrade the 1st and 2nd gear shift with the SONNAX Power Gear, 2.84 Ratio Input Carrier Kit so that it doesn't drop in rpm as much at WOT. This mod alone is worth from 3/4 tenths in the 1/4 depending on final gear. First gear is a close ration 3.06 which is low, but 2nd is a killer for performance in stock configuration. The 2.84 to 1 first gear, 1.56 to 1 second gear, 1 to 1 third gear and .70 to 1 overdrive ratio would be the ratio after the conversion. I would also suggest going to a higher stall, say...3500 and a rear gear of 3.31- 3.45ish. if you build the motor right and you have a lot of torque, you won't need tons of gear to get you going, but the 3500 stall should launch it pretty good, I know mine does and I use a 3.31. I think that just about covers the major things, but there is always something that you will want to do after it's running...IT NEVER ENDS. One last thing, if you really want a performer, build a 421 SB and use aftermarket EFI system.

Look at my stuff in my sig, it is close to being up to date. There is a lot of things you can do, but again, how deep are your pockets? Good luck which ever you decide.

 

I was wondering how you felt about trying to use the stock system vs skipping right to aftermarket.

If it were me and after having just messed with a truck with a 7747 ecm, I would start with a 350 roller cam motor, build your 383, pick your heads and cam then do aftermarket efi or ls swap it.

 

Buccaneer,
Thanks for the suggestions. Have not tuned via laptop before so will be a huge learning curve. If i went ahead and converted to carb would the programming still be neccessary upfront, or could it run effectively before needing tune? We just pulled the motor this week and need to start disassembly and getting together parts, so have some time before decisions need to be made with the TBI vs carb.

Chris

 

If you want to keep the stock CFI system from the intake up, you can with a mildly modded 350-355 motor and which you could still use the stock ECM. It's the "cam duration" you choose that will kill you using a stock ECM. You can not stray too far from stock without having issues. A lumpy cam with a stock ECM don't mix, the MAP sensor bouncing around will cause the ECM to wig out and you will NOT be able to tune it out. Also, the stock TBs would be OK to some degree with bigger injectors, but you would have to go to an external regulator to bump up the FP to feed the motor and the stock FPR would NOT be reliable at that point and you stand a good chance of rupturing the bladders and fuel going going all over your nice hot motor. Less air with smaller TBs would be an issue at some point as well. Make sure you carry a fire extinguisher if you go the stock route with high FP, you may need it fast. I personally have ruptured a brand new set of bladders when the FP went over 25psi. Luckily it was only on a cold motor and only started to crank. It was all about experimentation way back then. Side note...Fiberglass burns pretty good, carry full coverage insurance also.

You could easily do that, if you want to find a roller block which adds to the overall cost. Nothing wrong with using a non-roller block and going to the retro roller kit. Once you go to the EBL FLASH II, you will be fine with a 7747 or 8746. The difference between the two really is the 8746 has IAT input which aids in tuning. Which also means you would have to add an IAT sensor in the airbox or wherever you wanted to put it. I'm actually working on another project with the Renegade right now which involves EFI, only started to scratch the surface and have a couple of issues to work out to make it all come together and I'm sure it may take a while, but I feel very confident that my motor will run even better with that setup. I hope this helps in some way and is just my opinion.

 

I dont have a CF was just curious what someone in the middle of modding one thought about it.

 

No problem, just putting it our there for others as well that might be considering mods.

 

Buccaneer,
Curious as to what fuel pump you are using to get 20-22 psi. I have done the parallel plumbing, 90lb injectors blocked off old fpr and compensator, aeromotive adj fpr and 85 tpi fuel pump. can only manage 17.5 psi or so with the fpr cranked up.

 

I use this one, direct fit and running 24psi right now. QUIET as hell and will flow more than enough for your needs. Enjoy! 255LPH pump
You will have to install the stiffer spring that came with the Aeromotive FPR to achieve the higher pressure though.

 

This is the FPR I use it is similar to the Aeromotive FPR that Buccaneer uses. You have to change out the spring to the High Pressure spring to get 16 to 65 from the system. https://www.jegs.com/i/Holley/510/12-880/10002/-1 I have 90# injectors with parallel plumbed lines and block off plates. Edit: Wrong link to pump I used: I used this pump https://www.summitracing.com/parts/d...1027/overview/ (Had to recheck build book.)
I am running 24psi.

 

Sweet thanks, just ordered one!
Just put in 90lb injectors and pretty much copied your setup for fuel plumbing, heads and of course the renegade, wow this thing scoots now!
Thanks for sharing your cross-fire knowledge through the years, very much appreciated!

 

Thanks for the info!
Forgot to mention that I had switched to the stiffer spring, I guess the 85 tpi pump pump just couldn't put out any more, won't be a problem much longer!

 

I think mine is marginal (165lph I used this pump https://www.summitracing.com/parts/d...1027/overview/) for the build I have, you need at least 255lph, Going to a 340lph for the 427SB I am going to replace the 355SB with. https://treperformance.com/i-1285334...1985-2004.html or https://www.jegs.com/i/JEGS/555/159030/10002/-1

Going to a Offenhauser 360 cross ram intake with adapter plates for the tbi.

 

Wow, sounds like you will be building a beast!
Look forward to seeing how it comes together!

 

Nice and thank you. looks very similar to mine. What cam did you go with? If it's like my current one and your tune is right on, you have a mid 12 sec CF. Gear and stall?

 

Nice job Buccaneer, the CF is just too cool lookswise. The fact you got it running 12s and looking pretty stock...awesome.
Some outside the box thinking can make anything run pretty good.

 

I have a crane 2030 that I put in many years ago. As far as stall and gear, I have no converter, running a T56 manual with 3.73 gears.
Definitely not a 12 sec car yet, bottom end is a 355 with that mild cam. Will eventually build a 383 or bigger with a more aggressive cam in the future. Not sure on HP where I am now, the top end is the same as yours, heads, rockers, injectors/tb's and using ebl flash, guessing maybe in the 325 to 350 range. Way better than stock for sure.

 

OK, thanks. I thought you had a 383, my mistake. How do you like the T56? So, when you do build one at some point, it will pick up about another 75-100hp at the motor and put you squarely into the mid 12s if that's what your looking for. I run a 9.5" Yank SS3200 stall, but going to a SS3600 when I pull the trans back out. That should help my 60ft a little more and drop my ET some more as well. I will be very happy at 12.40, but will still try for the 12.20s.Done right, a CF motor will haul *** on just two injectors. PM sent.

 

Love the T56, funnest project yet on the car. With the 3.73 gears it runs at the same rpm as the 700r4 on the highway and nice lower gear ratios. Used one from a Lt1
f body, tight fit but it works.
Sweet, 70-100 extra horses would be awesome! Hoping to be around 450 horses when all is said and done, that was a pipe dream many years ago when I bought my vette.
You are putting down some good times there, but that has some people scratching their heads when they find out a cross-fire is under the hood! Great job with your build, it is amazing what just two injectors can do!