1979 SA RX-7 LS Turbo Build (8.93 @ 153)

[forcefed86]

CF Hood finally came in. Got rid of the hood pins and installed a factory latch. Just need to find some street legal tires and I can go try to tag this thing.

[Burntz]

damn that thing looks legit

[screamin88]

Looks good! Before you get dot skins.... Let's see some wheelstand pics/vids!

[cyipher]

who makes that hood? do they may any other rx7 body parts?

[forcefed86]

Hoping to avoid the wheel stand scenario. At least until I get comfortable with it. The front struts and springs are really weak, so if I come down hard at all it won't be pretty!

  DOT tires won't be on it for long though. I run the slicks on the street year round. Just borrowing a set to get past inspection. (hopefully anyway)

It's a "fibermaz" hood. (or at least I was told so).Don't know much else about it. The company made quite a few FB parts. He was all over rx7club.com and ebay a few years back. Not sure what happened to them.

 Only found one company willing selling these at a decent price. ($630 shipped) but I was looking at a 5 week waiting period. One guy sells them on Ebay for $755 shipped. Those are the only two companies I found that sell them.


 

[SSjon]

Looking really nice!

Waiting for some 1/4 numbers... 

Anyone know if FB hood fits SA? I know the fenders and bumpers are different but not sure aboot the hood.

[forcefed86]

Shot down at the tag office today.    Of all the legit things they could have failed me on, they called me out on the missing odometer. It says "Mileage Exempt"  in huge letters on the title. The inspector even told me it didn't have to work, just had to be there. 

Oh well, I suppose it could have been worse. Ordered a 6 digit hour meter online. (hard to find a small odometer with out a speedometer attached) I'll velcro the bastard in and head back next thursday... 

 

[cool]

Hehe I like how you think.  The car looks absolutely wicked. 

[forcefed86]

Well I cruised out to the track. Didn't know tomorrow was a mako event and only got two runs.

I've had no WOT tuning before tonight. 

8.5 psi (as low as It would go) it went 11.2 @ 125. Lazy 1.7 60 ft.

It launched ok, then bogged pretty hard in the 10.5 AFR range from 3500-4600 or so and cleaned out a little at 5300 where I shifted. My AFR looked to be in check the whole run can't figure out why it bogged. I'm leaning towards timing. My map has a big dip in the middle the slowly ramps up.



Tried to turn up the boost to 12psi and it just fell on its face. I think this is because timing went from 15* at 8psi to 11-12* at 12 psi. AFR was in the mid 10's. 

I've heard some people with the dished 5.3 with 6.0 heads  needed a ton of timing to get it running well. I think that may be my issue. With the dished pistons, 6.0 heads and zr1 cam my Dynamic CR is under 7:1. I need to get this on a dyno and play a bit. 

Still a fun night... and I drove it home. 


 

[Burntz]

Im a pretty big tuning noob but afr's should be 11-12 ideally at full boost right? Unless you're being super safe. And yea iv heard the engines love timing ESPECIALLY with e85. What are your fuel pressures? And what plugs are you running? No boost leaks right?

[SOB Racing]

I tuned for 12.5 on my turbo 4.   11-12 is safe, 10 your are just wasting fuel.   

[zbrown]

Every combo wants something different and that is a fact

Watch your plugs and start tame just like you are

[forcefed86]

Thanks for the input all.

 I've tuned quite a few different e85 setups. You don't tune a 2 valve "big cube" motor like you tune the dohc 4 valve baby cube motor. I tune to 11.5-12.0 on my 2 liter as well. I like ot keep a new tune in the mid to high 10's until I know "whats what".

Also found e85 does not necessarily like or need higher timing. All depends on the setup. This motor has pretty low SCR to start with and the cam is dropping the DCR to the 6.5-7:1 range depending on which calculator I use. So with this odd ball combo I may need more timing than most until I get the cylinder pressures up.

I pulled all the plugs. They look great, nice light grey color. Don't appear to have much variation across the board, no speckling, and the heat line was about half way up the strap. Trying to schedule some dyno time and I'll inch up the timing a bit and see how it reacts. 

[cyipher]

Thanks for the input all.

 I've tuned quite a few different e85 setups. You don't tune a 2 valve "big cube" motor like you tune the dohc 4 valve baby cube motor. I tune to 11.5-12.0 on my 2 liter as well. I like ot keep a new tune in the mid to high 10's until I know "whats what".

Also found e85 does not necessarily like or need higher timing. All depends on the setup. This motor has pretty low SCR to start with and the cam is dropping the DCR to the 6.5-7:1 range depending on which calculator I use. So with this odd ball combo I may need more timing than most until I get the cylinder pressures up.

I pulled all the plugs. They look great, nice light grey color. Don't appear to have much variation across the board, no speckling, and the heat line was about half way up the strap. Trying to schedule some dyno time and I'll inch up the timing a bit and see how it reacts.

I recently changed to E-85 and i can tell you that when my car went into the mid 10's afr (gas range) I would have a issue with the car ramdom breaking up. I was an issue with my wideband formula once i fixed this and got my afr to 11.8-12.0 the issue went away. Also dont rely on specking of the plugs with E-85, due to the lower carbon build up from e-85 you may not have any carbon to knock off the piston and on to the plugs.

[forcefed86]

I recently changed to E-85 and i can tell you that when my car went into the mid 10's afr (gas range) I would have a issue with the car ramdom breaking up. I was an issue with my wideband formula once i fixed this and got my afr to 11.8-12.0 the issue went away. Also dont rely on specking of the plugs with E-85, due to the lower carbon build up from e-85 you may not have any carbon to knock off the piston and on to the plugs.

Where is your 02 sensor located? I was getting false rich readings when I had mine in the manifold. Moved it to the muffler tip and it read quite a bit leaner. I know Scottie and a few others run on the rich side with no issues. I had planned on leaning it out a bit on the dyno.

Do you use your knock sensors? Mine were going bat shit at 1-2psi and pulling a ton of timing. I ended up shutting them off. I was seeing 3.1v (5v is max) or so on the 8psi pull. I assumed this was just due to the solid motor mounts and or noisy glide sending odd ball harmonics through the block.

 I was thinking I’d wedging my WG open to get little to no boost.  Then datalog what’s considered a “normal” amount of noise (voltage) on my knock sensors. Then setting the sensors up to pull timing if that normal point is exceeded. But if I'm already getting 3+v the engine may just be to noisy to pick up knock properly.

I was ASSuming I wasn’t detonating at 8psi, but I don’t know how I’d tell if I can’t use the plugs. Pretty sure speckling (at least major detonation) is the result of alum specks from the CC. Defiantly saw speckling on my E85 buick and 4g63. Can see a tiny bit of pitting on the pistons usually as well.

This is 34psi and to much timing on my e85 4g63.




On a side note...
 
Swapped in a larger area filter. Still on the small side, but I'm claiming average now.