Increased HP?

ghoztdawg2 · Post by **ghoztdawg2** » Fri Jul 21, 2006 6:36 pm

Hi- I have a 1980 Spider. I am replacing my 4-1 ehaust with a stock 4-2-1 system and replacing my ADHA dual plane carb and intake with a ADFA single plane. How much increase in HP should I expect and will there be
a significant increase in performance?
Thanks for any info.

So Cal Mark · Post by **So Cal Mark** » Fri Jul 21, 2006 8:55 pm

hp ratings were the same between the two setups, but the car is much more responsive with the carb/intake swap. Don't expect to turn it into a race car with the conversion though

Joe Clemente · Post by **Joe Clemente** » Fri Jul 21, 2006 11:26 pm

Mark's right,

You'll get a bit more pep but hp gains will be negligible. If you want a significant boost in power you'll need to look at mounting dual carbs, better cams, higher compression and a better exhaust.

racydave · Post by **racydave** » Mon Jul 31, 2006 7:02 am

I did the intake, carb on my 79, w 4-2-1. played w centrifigal advance springs yesterday, big improvment, she screams!!! Im grinnin!!!

ghoztdawg2 · Post by **ghoztdawg2** » Mon Jul 31, 2006 5:45 pm

RacyDave -sounds great, that is exacyly what I am hoping to see. Did you have a lot of trouble with the exhaust manifold bolts? Did you do both conversions at one time and was the 2-1 down pipe bottom connection much of a problem? Thanx for you input.

bandit · Post by **bandit** » Tue Aug 01, 2006 2:43 pm

what did you do with the springs ?? replace them or use stock ???

Dan

bandit · Post by **bandit** » Tue Aug 01, 2006 2:43 pm

what did you do with the springs ?? replace them or use stock ???

Dan

racydave · Post by **racydave** » Tue Aug 01, 2006 7:02 pm

Luckilly, mine had the exhaust as stock item, I still had some springs from my small block days, they fit good. you have 2 stronger springs, these were replaced with weaker ones. I gained more initial advance, made it more responsive. Its hard to achieve base timing, and total advanced timimg with a vaccume advance, even if you use ported or part throttle vaccume ,so I disconnected it, will also remove it. before checking the timing, I drove her, wow, but it was to good at 50deg BTDC. I bought a timing light from sears with a dial, adjusted base to 10 BTDC, and total at 35 BTDC, had to slow Idle down, and re adj carb. My car idles better, and runs smoothly, with great pick up. I was fast enough to purchace on line, a 36 adl webber with manual secondaries, and a intake from a 1800 with the single plane design for the carb, which was from a 2L lancia.There are some good info regarding these mods. My carb is probally just a little rich, but all the tweaks are getting it closer, and I havnt lost my cat converter, yet..... Its nice to have something work out, me and wife enjoy drivin evening rides, and I go farther every weekend, soon to Mich? Dave

Mark_vaughn · Post by **Mark_vaughn** » Wed Aug 02, 2006 10:40 am

The 36 ADL is the key. It is compared in performance to dual carb setup. Where did you find it? I have been searching for a while.

racydave · Post by **racydave** » Wed Aug 02, 2006 6:16 pm

Another Fiatweb site, a nice helpfull fella from New Jersey, I dont think it was for sale for long, I jumped on it fast, he also had the intake. Its probably the equivilent to the euro Fiat version, many were 4 carb set ups.Carb info via WWWmirafiori.com very helpfull!!! Dave