BritishV8 Forum

General Category => Engine, Transmission, & Rear Axle assy. => Topic started by: roverman on January 24, 2019, 06:28:29 PM

Title: RV8 with Sidedraft Webbers ?
Post by: roverman on January 24, 2019, 06:28:29 PM
DCO's available in 48, 50 and 55mm, all same price.  My Mickey Thompson/Indy manifold is 50 mm at  port inlet ? Race only ! Street DCOE's are 45mm, and much less $'s. Anybody versed with these carbs ?   Thanks, art.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: Bland on January 24, 2019, 09:36:24 PM
Art,

I have worked with sidedraft webers on Cosworth and Toyota Atlantic motors.  Are you asking if 45's will work?  What is the engine displacement and is this for your GT1 drag car?

Have you spoken with Pierce Manifolds?
Title: Re: RV8 with Sidedraft Webbers ?
Post by: 4.6 MGB V8 on January 26, 2019, 12:14:06 AM
A fellow named Costello was way back in the beginning 😆. Mounted on a rear facing manifold to clear the bonnet. I think he used 45's but I've been looking for one of the larger DCO's for a while with no luck. There are also the dual and quad manifolds you are probably familiar with.
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Title: Re: RV8 with Sidedraft Webbers ?
Post by: roverman on January 29, 2019, 04:04:12 PM
The MT. DCO(E), manifold is I.R., so 4 carbs.  I suspect that (4) 45 DCOE's will get the flow/hp. I need,(400-500). ? Why spend $700 more,( DCO'S), if not needed ? I suspect Pierce my not welcome another competing manifold ?   art.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: roverman on January 29, 2019, 04:43:38 PM
Tim, Displacement to be 4L," IF" I can get crank down to 2.8" stroke. Otherwise 4.2-4.5L ?
Title: Re: RV8 with Sidedraft Webbers ?
Post by: roverman on February 06, 2019, 04:21:41 PM
Since I want to use E85 and Webbers won't like, I have Hilborn Inj. Likely I'll increase butterflies to 2".
Title: Re: RV8 with Sidedraft Webbers ?
Post by: tr8todd on February 06, 2019, 05:25:44 PM
I've seen a couple of stroker engines with Weber's and then 4 barrel harcourt open plenum manifolds. Dyno results were just about interchangeable.   I've also seen well tuned 4 barrels replaced by 4 barrel looking fuel injection systems.   Peak horsepower remained the same, but just about everywhere under the curve was 10 to 15 ft pounds better with the fi. Unless you are going for the cool factor, just install a Fitech or similar system and be done with it. My 4.6 powered coupe is getting the 400 hp capable fitech on an edelbrock. Should make for a nice 250 plus hp driver and that's more than I can make on the SCCA ITS race car by about 75 hp. On a British race car, it's more about reliability and repeatability than it is about peak hp.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: roverman on February 06, 2019, 07:17:34 PM
Todd, well taken-but, MT "Indy" is way cool. All 8 runners are 8.0" long on short side. Should boost mid-range torque. Cross ram means no hood bulge/etc.(nasty sleeper). True, tuned length, IDF's can get there, but above std. hood height. I would like peak power at 8k + rpm. Ported TA's , E85 and high effective comp ratio, I'm aiming for 400+ hp. Obviously induction go back to Huffaker 4 bbl and gas, for SCCA.
                                                                       zoom-zoom, art.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: tr8todd on February 07, 2019, 08:32:35 AM
Yep, really cool, expensive, time consuming to tune, etc.  Untiil the car is actually out there turning laps, its all just bench racing anyway.  We can talk what ifs all night long, or you can slap a 4 barrel on it and get out there.  Worry about the finer details after you spend a bunch of money on tires and entrance fees.  Are after market heads even allowed?  I doubt it, unless some of the vintage racing series look the other way.  What good is a race car if it isn't racing?  I got two of them just collecting dust and taking up valuable garage space.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: roverman on February 07, 2019, 11:07:28 AM
Todd,  Ow !  Agonizing reappraisals.....   A: limited term straight line racing, 1/8-1 mile events. Hilborn on road course, not-so-good. B: Until I'm really ready for vintage road race events, Huff will showcase/ prove worthiness of products I am manufacturing. C: such as bell housings, auto trans, 8 port cross ram intake, and roller cams. Old school Hilborn, for straight line work, pretty easy to tune.
                                                                         zoom zoom, maybe happen, art
Title: Re: RV8 with Sidedraft Webbers ?
Post by: Bland on February 07, 2019, 02:45:09 PM
ART,

Sent you a PM regarding the cross ram intake.
Title: Re: RV8 with Sidedraft Webbers ?
Post by: Sidecardoug on June 16, 2019, 03:06:47 AM
You might want to contact Borla- they make a nifty fuel injection system that looks like cross ram Webers, without all the tuning hassles - like adjusting for altitude, etc.  I've seen several on Cobra repops and others, and they all ran well on the street.