Installing a V-8...a few questions, Progress thread & 914 makeover Options

[computers4kids]

Today I had the chance to put my car on a chasis dyno and get a starting point for some tuning to come. It produced 305 lbs of torque at the rear wheels in 4th gear. I'll have to play with the timing and throttle linkage before I run it again. I would also like to put on a quieter set of mufflers to replace the turbos...they sound great, but a little too loud for me below 2,000 rpm (IMG:style_emoticons/default/biggrin.gif)

https://www.youtube.com/watch?v=l0z5TV72aFo

Dyno Video

[JRust]

(IMG:style_emoticons/default/drooley.gif) (IMG:style_emoticons/default/drooley.gif) (IMG:style_emoticons/default/drooley.gif) (IMG:style_emoticons/default/drooley.gif) (IMG:style_emoticons/default/drooley.gif)
I love v8 914's (IMG:style_emoticons/default/aktion035.gif)

[dkjens]

That thing is so quiet, how can you think it's loud? And the only time it spends under 2000rpm is when at a red light he he.

[dakotaewing]

What was the HP?

[pjhaun]

What was the brand name of the Dyno machine?

[slow914]

What are you plans now, that car is so dialed and tight I cant imagine improving on it? (IMG:style_emoticons/default/popcorn[1].gif)

[computers4kids]

What was the HP?

Well, that's a good question. My torque curve was no where near maxed and steadily climbing, but I couldn't get the rpms. This motor is a 305 truck motor that was built for a circle track car and should rev in the 6-7 range with no problem. I wasn't getting even near that. All I know about the motor is it was new, has headers, Eldebrock torquer manifold, 650 carb, cam for sure but who knows what (sounds pretty healthy) vortec heads and roller rockers. Unfortunately, the motor was built by a shop for another person. It would help to know what really is inside. It has about 250 miles on the motor now. So, a combination of not getting full throttle, possibly not enough full advance and maybe under carbed kept the rpms down. I'm thinking it shoud break 300, but looks to be around 270 now to the rear wheels--not sure. I was really kind of suprised because the car really hauls ass. This motor stock is used to hauling around a 5,000 pound trunk, so with that kind power curve in a 914 that's 1/2 of that, well....makes for a nice ride.

What was the brand name of the Dyno machine?

PowerDyne SuperFlow WinDyn V

What are you plans now, that car is so dialed and tight I cant imagine improving on it? (IMG:style_emoticons/default/popcorn[1].gif)

Well, I'm perfectly happy with the car now, other than I want to make it quieter under 2,000 rpm. For me, I just want to make sure that the motor is tuned for the street and getting what it is capable of under those conditions.

You can't imagine the grin on my face when some guy is showing off for his gal in his hot rod next to me, only to be handed his lunch by a 914 VW Porsche (IMG:style_emoticons/default/happy11.gif)

[JRust]

Amen Brother! I wasted some little shit with his girlfriend just the other day. Was funny to see the surprise on his face. Of course I only do it to 60 just to show them it's there. I don't want to get a ticket or cause any traffic problems. Funny when they catch up though (IMG:style_emoticons/default/lol-2.gif) . You can see the what does he have in there look???

On another note Mark I found a compete FI sysytem for my car. I am still researching it but it is a birect bolt on deal. Wiring everything will be a bit of a chore but doesn't look to extreme. I've got some good articles from the MGv8 guys on it. My worry is height wise. DOesn't look lik eit sits up much higher than my carb but probably does. So I'll have to check that out when it arrives.

Cool to see that dyno run. Kind of a trip watching your wheels cranking away while your car doesn't move (IMG:style_emoticons/default/blink.gif)

[charliew]

302 z28's were advertised at about 390 hp stock without headers. They were really about 425-450 hp. with headers and maybe a 700 cfm carb at about 7200rpms. They did not have heads as good as vortec's. 650cfm is enough carb for 400 hp at 6-7k in a 302. If the motor was built for a truck it could have a high torque low rpm cam. You need at least 1/2 inch of lift at the valve. About 36 degrees total with 10 initial advance. A high reving sbc really needs a good ati balancer to keep the crank balanced at high rpms.

A good thing is the 901 might live a little longer with only 300ft lb.

[dkjens]

My 283 is running like crap right now, could it be the Edlebrock 750 carburetor he he. The plugs look perfect but you can smell the fumes when driving and it's not untill you floor it that it runs well without misses. I am looking for a 550-600cfm carb right now.
I am going to buy a 350 back from a friend I sold it to. I will also get a sb ch single turbo set up with it. I will run the 350 while rebuilding my 283 for turbo. I have a set of LT1 heads and intake manifold from a Camaro. I will modify those heads and use them with the intake, run 8.0:1 or 8.5:1 compression, build a Megasquirt fuel injection system and run a big ar.. untercooler in my trunk lid.
Compared to the 350, I really like how the 283 likes to spend its time at 3000+ revs, it just isn't strong enough as is, but that can and will be changed.

[charliew]

dkjens, Lt1 is reverse flow coolant isn't it? also the ports are different for the intake and there isn't a distributor on the LT1 intake. The waterpump runs off the camshaft and the ignition is under the waterpump on the front. Do you mean cast iron vortec heads?

[dkjens]

charliew,
Yes, I know the LT1 is not a bolt on head, but it can be modified to work on a gen 1 engine. I will probably use an EDIS8 for ignition and a Megasquirt for fuel injection and the LT1 Camaro intake manifold.

[marks914]

I had a 305 in mine before I went to the 302 The 305 is a good, torquey engine, the shortcoming is the heads. The Vortech heads is the way to go, the small bore on the 305 does not lend itself to the larger valve heads from larger bore blocks. You should be able to get well over 300HP out of it, but the long stroke is more for torque, not rpms. Also, if you want to spin it over 6400, you really need some trick valvetrain, or solid lifters and ignition. My HEI gives up 6500-6700, kind of a built-in rev limiter. The valves start to float around 6700, but I am running full roller hydraulic lifters.The 305 is now in my 35 chevy, which I really need to work on and get on the road st some point.
If you want to quiet it down a bit, try some resonator tips. Worked wonders on my car. The neighbors were getting upset when I pulled between the houses at 5:00 in the morning.

Your car is looking good.

Mark

(IMG:http://inlinethumb21.webshots.com/6292/2135067100057582025S600x600Q85.jpg)

(IMG:http://inlinethumb45.webshots.com/41964/2511335820057582025S600x600Q85.jpg)

[computers4kids]

If you want to quiet it down a bit, try some resonator tips. Worked wonders on my car. The neighbors were getting upset when I pulled between the houses at 5:00 in the morning.

Adding resonator tips was one of the options I'm exploring. In my setup I have dual tips on turbo mufflers, in other words I would have to purchase 4 resonator tips which would run over $100. Now, if the tips would do the trick then I'd pull a a bill out of my wallet pretty fast. I'm just not to sure how much it's going to make a difference. You feel it made a significant impact to the noise level of your car? I presume you had the low end resonation/drone before you added the tips...or just loud?

I've also seen "insert" options as well: cones or baffles. That option will cost about $150...but do they work is the question. You can insert the cone after the headers or before the muffler



I just don't have any room for larger mufflers or that would make the most sense...plus my turbos are brand new, but hey there in the trash can if I can find a better option. I even thought about an additional inline glass pack before the axle...but no room again, unless I go to short headers. When I added a crossover pipe it helped a ton, but I want the low end drone gone (mostly).

Now, Drivability I heard has a tone port connected to his exhaust. I just don't know how that works--I meant to connect with him at Cars and Coffee in Irvine but I forgot.

So what-do-ya-think? Resonator tips...diff. mufflers, inserts, dynomat or ? (IMG:style_emoticons/default/popcorn[1].gif)
Oh, there is one other option...never drive slower than 2,000 rpm (IMG:style_emoticons/default/biggrin.gif)

[messix]

If you want to quiet it down a bit, try some resonator tips. Worked wonders on my car. The neighbors were getting upset when I pulled between the houses at 5:00 in the morning.

Adding resonator tips was one of the options I'm exploring. In my setup I have dual tips on turbo mufflers, in other words I would have to purchase 4 resonator tips which would run over $100. Now, if the tips would do the trick then I'd pull a a bill out of my wallet pretty fast. I'm just not to sure how much it's going to make a difference. You feel it made a significant impact to the noise level of your car? I presume you had the low end resonation/drone before you added the tips...or just loud?

I've also seen "insert" options as well: cones or baffles. That option will cost about $150...but do they work is the question. You can insert the cone after the headers or before the muffler



I just don't have any room for larger mufflers or that would make the most sense...plus my turbos are brand new, but hey there in the trash can if I can find a better option. I even thought about an additional inline glass pack before the axle...but no room again, unless I go to short headers. When I added a crossover pipe it helped a ton, but I want the low end drone gone (mostly).

Now, Drivability I heard has a tone port connected to his exhaust. I just don't know how that works--I meant to connect with him at Cars and Coffee in Irvine but I forgot.

So what-do-ya-think? Resonator tips...diff. mufflers, inserts, dynomat or ? (IMG:style_emoticons/default/popcorn[1].gif)
Oh, there is one other option...never drive slower than 2,000 rpm (IMG:style_emoticons/default/biggrin.gif)

i have an idea!.......... buy a honda!...... suck it up your driving a HOT ROD for gods sake! what... are old or some thing! jeez you old geezer! (IMG:style_emoticons/default/happy11.gif)

really how bad is it?

btw niether of those "baffles" shown will help you low freq problem, those are "racin mufflers " and do not attenuate the sound much at all.

[charliew]

Sometimes the drone can be improved with better timing and also the long headers can be causing it in the collector. I haven't tried it but the insert in the collector might help, it's really a muffler for street rods that are only running headers though. Or drag cars that have to have a lower exhaust level. Higher compression also will cause a drone. You might want to check up on supertraps as they can be adjusted with more or less diffuser plates.

I wonder if dkjens realizes that the vortecs are the cast iron equalivent of the lt1 aluminum heads but were cast iron for the chev trucks. Same port and combustion and valve configuration but designed for the top distributor. If you want aluminum heads go with the new design heads that everyone made to copy the vortec design.

[computers4kids]

Silence is Golden (IMG:style_emoticons/default/piratenanner.gif) Problem solved...gone, adios...with just $3 of stuff from the hardware store.

Initially, when I first was putting my car together my turbo mufflers had just the one outlet on both sides of the car (single in and single out). I wanted dual tips so I had the muffler shop weld on dual chrome tips on both sides of the car and customized the lower valance. Obviously one tip went on the muffler stub and the other was just welded to the back end of the muffler. OK, so now I ask the muffler shop to blow a hole in the end of the muffler inside the tip so exhaust is coming out of both tips. I asked if that was going to be a issue and they said "shouldn't make a difference." The car didn't have exhaust when I first came in so I had no comparison when I had left.





Fast Forward. After reading and reading, I kept having this nagging feeling that perhaps I didn't have enough back pressure in the muffler for it to work as designed. So today I looked down inside the tips with a flashlight and I could see the difference between the real outlet and the one I had added on. The way the chambers in muffler was designed, I essentially had created a way for the exhaust to pass right through the muffler. To see if my hunch was correct, I built some block off plates and bolted them in the second tip on both side sealing it back to original as a temporary measure.





Low and behold, my car was an entirely different animal afterwords...all my problems of resonance went away and the car mellowed out considerably. (IMG:style_emoticons/default/piratenanner.gif) (IMG:style_emoticons/default/piratenanner.gif) Perfect! So "messix" the old geezer is finally happy. I'm driving my "hot rod" with a smile on my face and my stereo on, OH, I can hear it now. (IMG:style_emoticons/default/smile.gif) Although, I will miss being able to set off car alarms just for fun (IMG:style_emoticons/default/happy11.gif)

Now, I'll probably just tack weld the block off plates permanently and call it a day.

[LS1944]

Great job! I have a chevy powered 944, it's a fun car but I can't imagine all that power and torque in a lightweight 914. Must be a blast!

Craig

[TC 914-8]

F--ing sweet Mark, Keep up the good work, well talk about it when you make it to the PNW.
Troy wishes he had a V-8 (IMG:style_emoticons/default/poke.gif)

[computers4kids]

Do I have a bullsyeye painted on my 914? Sure seems like it...the last two times I drove it downtown I almost got creamed. I decided to add a 3rd brake light, not stock, but maybe it'll help. Oh, I guess I don't have to worry about not being stock (IMG:style_emoticons/default/biggrin.gif)